[top]
000
FXUS63 KDMX 040420 AAC
AFDDMX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
1120 PM CDT FRI JUL 3 2009
.AVIATION DISCUSSION 04/06Z.
.SHORT TERM...
THOUGH THUNDERSTORMS CONTINUING TO DEVELOP UPSTREAM OF CWA
ATTM...NORTHERN AREAS HAVE BEEN SEEING GENERALLY MODERATE SHOWERS
THIS EVENING AND LACK OF INSTABILITY OVERNIGHT POINTS TO CONTINUED
SHOWERS THIS REGION VERSUS THE CHANCE FOR THUNDER YET ACROSS THE
SOUTH. SUBJECTIVE UPPER AIR ANALYSIS SHOWING THE BEST UPPER LEVEL
BOUNDARY AT H850 LIES OVER NORTHERN NEBRASKA AND KANSAS. INCREASING
LLVL JET BEGINNING TO PRODUCE STORMS FARTHER NORTHWEST INTO
SOUTHEAST NEBRASKA...BUT CORFIDI VECTORS AND PRESENT STORM MOTION
SUGGEST THAT AN ESE TURNING WILL OCCUR WITH TIME OVERNIGHT.
THUS...HAVE TRIMMED BACK AREAS OF HEAVY RAINFALL TO A MORE SOUTHERN
TRACK DURING THE OVERNIGHT HOURS AND HAVE ALSO CUT BACK ON QPF
AMOUNTS CENTRAL AND NORTH. THOUGH HIGH POPS ARE STILL WARRANTED MOST
AREAS OVERNIGHT ...CORRIDOR OF HEAVIEST RAINFALL APPEARS TO BE
FOLLOWING THE GFS THINKING FROM EARLIER THIS AFTERNOON...WITH HIGHER
TOTALS SOUTH OF I80 AND ESPECIALLY INTO KS/NORTHERN MO DURING THE
NIGHT TONIGHT.
.PREVIOUS SHORT TERM...
RAINY NIGHT ON TAP FOR THE SERVICE AREA. LOW PRESSURE CONTINUES TO
SLOWLY DEEPEN OVER KANSAS WITH A WARM FRONT GRADUALLY DEVELOPING
ACROSS NORTHERN KANSAS AND INTO MISSOURI. MEANWHILE A SERIES OF
SUBTLE SHORTWAVES IS APPROACHING FROM THE HIGH PLAINS AND WILL CROSS
OUR AREA OVERNIGHT. WIDESPREAD SPRINKLES AND SCATTERED LIGHT SHOWERS
HAVE BEEN DEVELOPING OVER EASTERN NEBRASKA AND WESTERN IOWA. AS THE
SHORTWAVES APPROACH TONIGHT...AND ATMOSPHERIC MOISTURE
INCREASES...COVERAGE AND INTENSITY OF PRECIP WILL INCREASE AS IT
SPREADS ACROSS THE STATE. PWATS ARE SUFFICIENTLY HIGH TO MAKE HEAVY
RAIN A CONCERN...ESPECIALLY IN THE SOUTHERN HALF OF OUR AREA. GIVEN
THE LIKELY HIGH COVERAGE AND LONG DURATION OF PRECIP
OVERNIGHT...HAVE OPTED NOT TO SPLIT OUT THE OVERNIGHT FORECAST INTO
TIME PERIODS GIVEN LOW DEGREE OF DIFFERENTIATION BETWEEN THE
RESULTING PERIODS AND THE COMPLICATED LANGUAGE IT WOULD INTRODUCE
INTO THE TEXT FORECAST. QPFS ARE DIFFICULT TO PREDICT TONIGHT GIVEN
DEPENDENCE ON TIMING AND MAGNITUDE OF SHORTWAVES...DEGREE OF
ENHANCED MOISTURE TRANSPORT...AND UNCERTAINTY REGARDING MAGNITUDE OF
INSTABILITY ACROSS THE AREA. IN ANY EVENT...SPRINKLES AND OCCASIONAL
LIGHT SHOWERS THIS AFTERNOON AND EVENING WILL GIVE WAY TO MORE
WIDESPREAD AND HEAVIER PRECIP OVERNIGHT.
.LONG TERM...
SFC LOW AND ASSOCIATED SHORTWAVE WL BE DEPARTING TO THE EAST ON
SATURDAY WITH RESIDUAL SHOWERS AND A FEW THUNDERSTORMS IN THE
MORNING...ESPECIALLY EAST. HOWEVER...WL SEE COVERAGE DECREASE AS
FORCING PULLS AWAY FROM THE STATE. CROSS SECTIONS CONTINUE TO
INDICATE FAIRLY SATURATED CONDITIONS IN THE LOW LEVELS THROUGH
SATURDAY WITH AMPLE CLOUDINESS IN PLACE KEEPING TEMPERATURES IN
CHECK. QUIET WEATHER IS THEN EXPECTED INTO SATURDAY NIGHT AND
SUNDAY AS NORTHWEST FLOW ENSUES. MODELS DO INDICATE SOME ISOLATED
SHRA ACTIVITY LATE SUNDAY AFTERNOON AND NIGHT WITH WEAK
SHORTWAVE/FRONTAL PASSAGE BUT SOUNDINGS RELATIVELY DRY. HAVE GONE
WITH NO POPS AT THIS TIME GIVEN LIMITED FORCING AND MOISTURE.
THEREAFTER...CONDITIONS APPEAR DRY INTO THE MIDDLE OF THE WORK WITH
AS NORTHWEST FLOW BECOME LIGHT AND MORE WESTERLY WITH UPPER RIDGING
BUILDING INTO THE REGION. WITH THICKNESSES INCREASING...WL SEE A
GRADUAL WARMING TREND DURING THIS TIME TO NORMAL OR ABOVE NORMAL
LEVELS.
&&
.AVIATION...04/06Z
APPROACHING WAVE OVERNIGHT...SHRA/TSRA ACTIVITY FROM KS AND NE WILL
EXPAND NORTH AND EAST INTO IOWA...THOUGH AS THE STORMS MOVE INTO
MORE STABLE AIRMASS...THUNDER CHANCES WILL BE MUTED NORTH THOUGH
RAINFALL WILL STILL BE PERSISTENT AND CIGS/VISBYS EXPECTED TO DROP
TO IFR RANGE AFTER SEVERAL HOURS OF RAIN. THUNDER WILL CONTINUE OVER
THE SOUTH AND WILL MAINTAIN EITHER VCTS OR TSRA IN KDSM AND KOTM
TAFS OVERNIGHT. ALL IN ALL...CONDITIONS SHOULD SLOWLY IMPROVE ON
SATURDAY AS THE SYSTEM TRANSLATES EAST. WE WILL HAVE MVFR CIGS AND
POTENTIAL REDUCTION IN VSBYS DURING THE MORNING HOURS FOLLOWING THE
RAIN. THOUGH WIDESPREAD RAINFALL EXPECTED OVERNIGHT...MUCH OF THE
AREA WILL HAVE STRATIFORM PRECIP...ESPECIALLY OVER THE NORTHERN
SECTIONS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...LEE/REV
AVIATION...REV
LONG TERM...COGIL
000
FXUS63 KDMX 040241 AAB
AFDDMX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
941 PM CDT FRI JUL 3 2009
.UPDATED PUBLIC DISCUSSION.
.SHORT TERM...
THOUGH THUNDERSTORMS CONTINUING TO DEVELOP UPSTREAM OF CWA
ATTM...NORTHERN AREAS HAVE BEEN SEEING GENERALLY MODERATE SHOWERS
THIS EVENING AND LACK OF INSTABILITY OVERNIGHT POINTS TO CONTINUED
SHOWERS THIS REGION VERSUS THE CHANCE FOR THUNDER YET ACROSS THE
SOUTH. SUBJECTIVE UPPER AIR ANALYSIS SHOWING THE BEST UPPER LEVEL
BOUNDARY AT H850 LIES OVER NORTHERN NEBRASKA AND KANSAS. INCREASING
LLVL JET BEGINNING TO PRODUCE STORMS FARTHER NORTHWEST INTO
SOUTHEAST NEBRASKA...BUT CORFIDI VECTORS AND PRESENT STORM MOTION
SUGGEST THAT AN ESE TURNING WILL OCCUR WITH TIME OVERNIGHT.
THUS...HAVE TRIMMED BACK AREAS OF HEAVY RAINFALL TO A MORE SOUTHERN
TRACK DURING THE OVERNIGHT HOURS AND HAVE ALSO CUT BACK ON QPF
AMOUNTS CENTRAL AND NORTH. THOUGH HIGH POPS ARE STILL WARRANTED MOST
AREAS OVERNIGHT ...CORRIDOR OF HEAVIEST RAINFALL APPEARS TO BE
FOLLOWING THE GFS THINKING FROM EARLIER THIS AFTERNOON...WITH HIGHER
TOTALS SOUTH OF I80 AND ESPECIALLY INTO KS/NORTHERN MO DURING THE
NIGHT TONIGHT.
.PREVIOUS SHORT TERM...
RAINY NIGHT ON TAP FOR THE SERVICE AREA. LOW PRESSURE CONTINUES TO
SLOWLY DEEPEN OVER KANSAS WITH A WARM FRONT GRADUALLY DEVELOPING
ACROSS NORTHERN KANSAS AND INTO MISSOURI. MEANWHILE A SERIES OF
SUBTLE SHORTWAVES IS APPROACHING FROM THE HIGH PLAINS AND WILL CROSS
OUR AREA OVERNIGHT. WIDESPREAD SPRINKLES AND SCATTERED LIGHT SHOWERS
HAVE BEEN DEVELOPING OVER EASTERN NEBRASKA AND WESTERN IOWA. AS THE
SHORTWAVES APPROACH TONIGHT...AND ATMOSPHERIC MOISTURE
INCREASES...COVERAGE AND INTENSITY OF PRECIP WILL INCREASE AS IT
SPREADS ACROSS THE STATE. PWATS ARE SUFFICIENTLY HIGH TO MAKE HEAVY
RAIN A CONCERN...ESPECIALLY IN THE SOUTHERN HALF OF OUR AREA. GIVEN
THE LIKELY HIGH COVERAGE AND LONG DURATION OF PRECIP
OVERNIGHT...HAVE OPTED NOT TO SPLIT OUT THE OVERNIGHT FORECAST INTO
TIME PERIODS GIVEN LOW DEGREE OF DIFFERENTIATION BETWEEN THE
RESULTING PERIODS AND THE COMPLICATED LANGUAGE IT WOULD INTRODUCE
INTO THE TEXT FORECAST. QPFS ARE DIFFICULT TO PREDICT TONIGHT GIVEN
DEPENDENCE ON TIMING AND MAGNITUDE OF SHORTWAVES...DEGREE OF
ENHANCED MOISTURE TRANSPORT...AND UNCERTAINTY REGARDING MAGNITUDE OF
INSTABILITY ACROSS THE AREA. IN ANY EVENT...SPRINKLES AND OCCASIONAL
LIGHT SHOWERS THIS AFTERNOON AND EVENING WILL GIVE WAY TO MORE
WIDESPREAD AND HEAVIER PRECIP OVERNIGHT.
.LONG TERM...
SFC LOW AND ASSOCIATED SHORTWAVE WL BE DEPARTING TO THE EAST ON
SATURDAY WITH RESIDUAL SHOWERS AND A FEW THUNDERSTORMS IN THE
MORNING...ESPECIALLY EAST. HOWEVER...WL SEE COVERAGE DECREASE AS
FORCING PULLS AWAY FROM THE STATE. CROSS SECTIONS CONTINUE TO
INDICATE FAIRLY SATURATED CONDITIONS IN THE LOW LEVELS THROUGH
SATURDAY WITH AMPLE CLOUDINESS IN PLACE KEEPING TEMPERATURES IN
CHECK. QUIET WEATHER IS THEN EXPECTED INTO SATURDAY NIGHT AND
SUNDAY AS NORTHWEST FLOW ENSUES. MODELS DO INDICATE SOME ISOLATED
SHRA ACTIVITY LATE SUNDAY AFTERNOON AND NIGHT WITH WEAK
SHORTWAVE/FRONTAL PASSAGE BUT SOUNDINGS RELATIVELY DRY. HAVE GONE
WITH NO POPS AT THIS TIME GIVEN LIMITED FORCING AND MOISTURE.
THEREAFTER...CONDITIONS APPEAR DRY INTO THE MIDDLE OF THE WORK WITH
AS NORTHWEST FLOW BECOME LIGHT AND MORE WESTERLY WITH UPPER RIDGING
BUILDING INTO THE REGION. WITH THICKNESSES INCREASING...WL SEE A
GRADUAL WARMING TREND DURING THIS TIME TO NORMAL OR ABOVE NORMAL
LEVELS.
&&
.AVIATION...04/00Z
COMPLEX MESO SCALE SITUATION CONTINUES TO DEVELOP ACROSS KS THIS
EVENING. AREA OF STRONGER THUNDERSTORMS AND HEAVY RAINFALL CURRENTLY
FORMING ALONG A STRONG WARM FRONT JUST SOUTH OF THE STATE ATTM. AN
UPPER LEVEL BOUNDARY AND SFC TROUGH OVER NORTHERN IA HAS ALOS
RESULTED IN THE FIRST WAVE OF SHRA/RA MOVING OVER THE FORECAST AREA
AT 00Z. WITH APPROACHING WAVE TNT...SHRA/TSRA ACTIVITY FROM KS AND
NE WILL EXPAND NORTHEAST INTO IOWA WITH TIME...THOUGH AS THE STORMS
MOVE INTO MORE STABLE AIRMASS...THUNDER CHANCES MAY BE SOMEWHAT
MUTED THOUGH RAINFALL WILL STILL BE PERSISTENT AND CIGS/VISBYS
EXPECTED TO DROP TO IFR RANGE AFTER SEVERAL HOURS OF RAIN. HAVE
BACKED OFF ON CATEGORICAL THUNDER MOST AREAS EXPECT FOR KOTM FOR
NOW...BUT WILL CONTINUE TO CARRY VCTS FOR MOST LOCATIONS GIVEN THE
POSSIBILITY OF SOME THUNDER. ALL IN ALL...CONDITIONS SHOULD SLOWLY
IMPROVE ON SATURDAY AS THE SYSTEM TRANSLATES EAST. BUT WITH THAT
SAID WE WILL HAVE MVFR CIGS AND POTENTIAL REDUCTION IN VSBYS DURING
THE MORNING HOURS FOLLOWING THE RAIN. THOUGH WIDESPREAD RAINFALL
EXPECTED OVERNIGHT...WILL CONTINUE TO MONITOR CONVECTIVE TRENDS
SOUTH OF THE REGION AND IF THE ACTIVITY SOUTH BEGINS TO REDUCE
CHANCES FOR NORTHWARD DEVELOPMENT LATER TNT...WILL MODIFY 06Z TAF
PACKAGE TO REFLECT IMPROVEMENT IN EXPECTED CONDITIONS FOR EARLY SAT
MORNING./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...LEE
AVIATION...REV
LONG TERM...COGIL
000
FXUS63 KDMX 032335 AAA
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
635 PM CDT FRI JUL 3 2009
.AVIATION DISCUSSION 04/00Z.
.SHORT TERM...
RAINY NIGHT ON TAP FOR THE SERVICE AREA. LOW PRESSURE CONTINUES TO
SLOWLY DEEPEN OVER KANSAS WITH A WARM FRONT GRADUALLY DEVELOPING
ACROSS NORTHERN KANSAS AND INTO MISSOURI. MEANWHILE A SERIES OF
SUBTLE SHORTWAVES IS APPROACHING FROM THE HIGH PLAINS AND WILL CROSS
OUR AREA OVERNIGHT. WIDESPREAD SPRINKLES AND SCATTERED LIGHT SHOWERS
HAVE BEEN DEVELOPING OVER EASTERN NEBRASKA AND WESTERN IOWA. AS THE
SHORTWAVES APPROACH TONIGHT...AND ATMOSPHERIC MOISTURE
INCREASES...COVERAGE AND INTENSITY OF PRECIP WILL INCREASE AS IT
SPREADS ACROSS THE STATE. PWATS ARE SUFFICIENTLY HIGH TO MAKE HEAVY
RAIN A CONCERN...ESPECIALLY IN THE SOUTHERN HALF OF OUR AREA. GIVEN
THE LIKELY HIGH COVERAGE AND LONG DURATION OF PRECIP
OVERNIGHT...HAVE OPTED NOT TO SPLIT OUT THE OVERNIGHT FORECAST INTO
TIME PERIODS GIVEN LOW DEGREE OF DIFFERENTIATION BETWEEN THE
RESULTING PERIODS AND THE COMPLICATED LANGUAGE IT WOULD INTRODUCE
INTO THE TEXT FORECAST. QPFS ARE DIFFICULT TO PREDICT TONIGHT GIVEN
DEPENDENCE ON TIMING AND MAGNITUDE OF SHORTWAVES...DEGREE OF
ENHANCED MOISTURE TRANSPORT...AND UNCERTAINTY REGARDING MAGNITUDE OF
INSTABILITY ACROSS THE AREA. IN ANY EVENT...SPRINKLES AND OCCASIONAL
LIGHT SHOWERS THIS AFTERNOON AND EVENING WILL GIVE WAY TO MORE
WIDESPREAD AND HEAVIER PRECIP OVERNIGHT.
.LONG TERM...
SFC LOW AND ASSOCIATED SHORTWAVE WL BE DEPARTING TO THE EAST ON
SATURDAY WITH RESIDUAL SHOWERS AND A FEW THUNDERSTORMS IN THE
MORNING...ESPECIALLY EAST. HOWEVER...WL SEE COVERAGE DECREASE AS
FORCING PULLS AWAY FROM THE STATE. CROSS SECTIONS CONTINUE TO
INDICATE FAIRLY SATURATED CONDITIONS IN THE LOW LEVELS THROUGH
SATURDAY WITH AMPLE CLOUDINESS IN PLACE KEEPING TEMPERATURES IN
CHECK. QUIET WEATHER IS THEN EXPECTED INTO SATURDAY NIGHT AND
SUNDAY AS NORTHWEST FLOW ENSUES. MODELS DO INDICATE SOME ISOLATED
SHRA ACTIVITY LATE SUNDAY AFTERNOON AND NIGHT WITH WEAK
SHORTWAVE/FRONTAL PASSAGE BUT SOUNDINGS RELATIVELY DRY. HAVE GONE
WITH NO POPS AT THIS TIME GIVEN LIMITED FORCING AND MOISTURE.
THEREAFTER...CONDITIONS APPEAR DRY INTO THE MIDDLE OF THE WORK WITH
AS NORTHWEST FLOW BECOME LIGHT AND MORE WESTERLY WITH UPPER RIDGING
BUILDING INTO THE REGION. WITH THICKNESSES INCREASING...WL SEE A
GRADUAL WARMING TREND DURING THIS TIME TO NORMAL OR ABOVE NORMAL
LEVELS.
&&
.AVIATION...04/00Z
COMPLEX MESO SCALE SITUATION CONTINUES TO DEVELOP ACROSS KS THIS
EVENING. AREA OF STRONGER THUNDERSTORMS AND HEAVY RAINFALL CURRENTLY
FORMING ALONG A STRONG WARM FRONT JUST SOUTH OF THE STATE ATTM. AN
UPPER LEVEL BOUNDARY AND SFC TROUGH OVER NORTHERN IA HAS ALOS
RESULTED IN THE FIRST WAVE OF SHRA/RA MOVING OVER THE FORECAST AREA
AT 00Z. WITH APPROACHING WAVE TNT...SHRA/TSRA ACTIVITY FROM KS AND
NE WILL EXPAND NORTHEAST INTO IOWA WITH TIME...THOUGH AS THE STORMS
MOVE INTO MORE STABLE AIRMASS...THUNDER CHANCES MAY BE SOMEWHAT
MUTED THOUGH RAINFALL WILL STILL BE PERSISTENT AND CIGS/VISBYS
EXPECTED TO DROP TO IFR RANGE AFTER SEVERAL HOURS OF RAIN. HAVE
BACKED OFF ON CATEGORICAL THUNDER MOST AREAS EXPECT FOR KOTM FOR
NOW...BUT WILL CONTINUE TO CARRY VCTS FOR MOST LOCATIONS GIVEN THE
POSSIBILITY OF SOME THUNDER. ALL IN ALL...CONDITIONS SHOULD SLOWLY
IMPROVE ON SATURDAY AS THE SYSTEM TRANSLATES EAST. BUT WITH THAT
SAID WE WILL HAVE MVFR CIGS AND POTENTIAL REDUCTION IN VSBYS DURING
THE MORNING HOURS FOLLOWING THE RAIN. THOUGH WIDESPREAD RAINFALL
EXPECTED OVERNIGHT...WILL CONTINUE TO MONITOR CONVECTIVE TRENDS
SOUTH OF THE REGION AND IF THE ACTIVITY SOUTH BEGINS TO REDUCE
CHANCES FOR NORTHWARD DEVELOPMENT LATER TNT...WILL MODIFY 06Z TAF
PACKAGE TO REFLECT IMPROVEMENT IN EXPECTED CONDITIONS FOR EARLY SAT
MORNING./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...LEE
AVIATION...REV
LONG TERM...COGIL
000
FXUS63 KDMX 032031
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
330 PM CDT FRI JUL 3 2009
.SHORT TERM...
RAINY NIGHT ON TAP FOR THE SERVICE AREA. LOW PRESSURE CONTINUES TO
SLOWLY DEEPEN OVER KANSAS WITH A WARM FRONT GRADUALLY DEVELOPING
ACROSS NORTHERN KANSAS AND INTO MISSOURI. MEANWHILE A SERIES OF
SUBTLE SHORTWAVES IS APPROACHING FROM THE HIGH PLAINS AND WILL CROSS
OUR AREA OVERNIGHT. WIDESPREAD SPRINKLES AND SCATTERED LIGHT SHOWERS
HAVE BEEN DEVELOPING OVER EASTERN NEBRASKA AND WESTERN IOWA. AS THE
SHORTWAVES APPROACH TONIGHT...AND ATMOSPHERIC MOISTURE
INCREASES...COVERAGE AND INTENSITY OF PRECIP WILL INCREASE AS IT
SPREADS ACROSS THE STATE. PWATS ARE SUFFICIENTLY HIGH TO MAKE HEAVY
RAIN A CONCERN...ESPECIALLY IN THE SOUTHERN HALF OF OUR AREA. GIVEN
THE LIKELY HIGH COVERAGE AND LONG DURATION OF PRECIP
OVERNIGHT...HAVE OPTED NOT TO SPLIT OUT THE OVERNIGHT FORECAST INTO
TIME PERIODS GIVEN LOW DEGREE OF DIFFERENTIATION BETWEEN THE
RESULTING PERIODS AND THE COMPLICATED LANGUAGE IT WOULD INTRODUCE
INTO THE TEXT FORECAST. QPFS ARE DIFFICULT TO PREDICT TONIGHT GIVEN
DEPENDENCE ON TIMING AND MAGNITUDE OF SHORTWAVES...DEGREE OF
ENHANCED MOISTURE TRANSPORT...AND UNCERTAINTY REGARDING MAGNITUDE OF
INSTABILITY ACROSS THE AREA. IN ANY EVENT...SPRINKLES AND OCCASIONAL
LIGHT SHOWERS THIS AFTERNOON AND EVENING WILL GIVE WAY TO MORE
WIDESPREAD AND HEAVIER PRECIP OVERNIGHT.
.LONG TERM...
SFC LOW AND ASSOCIATED SHORTWAVE WL BE DEPARTING TO THE EAST ON
SATURDAY WITH RESIDUAL SHOWERS AND A FEW THUNDERSTORMS IN THE
MORNING...ESPECIALLY EAST. HOWEVER...WL SEE COVERAGE DECREASE AS
FORCING PULLS AWAY FROM THE STATE. CROSS SECTIONS CONTINUE TO
INDICATE FAIRLY SATURATED CONDITIONS IN THE LOW LEVELS THROUGH
SATURDAY WITH AMPLE CLOUDINESS IN PLACE KEEPING TEMPERATURES IN
CHECK. QUIET WEATHER IS THEN EXPECTED INTO SATURDAY NIGHT AND
SUNDAY AS NORTHWEST FLOW ENSUES. MODELS DO INDICATE SOME ISOLATED
SHRA ACTIVITY LATE SUNDAY AFTERNOON AND NIGHT WITH WEAK
SHORTWAVE/FRONTAL PASSAGE BUT SOUNDINGS RELATIVELY DRY. HAVE GONE
WITH NO POPS AT THIS TIME GIVEN LIMITED FORCING AND MOISTURE.
THEREAFTER...CONDITIONS APPEAR DRY INTO THE MIDDLE OF THE WORK WITH
AS NORTHWEST FLOW BECOME LIGHT AND MORE WESTERLY WITH UPPER RIDGING
BUILDING INTO THE REGION. WITH THICKNESSES INCREASING...WL SEE A
GRADUAL WARMING TREND DURING THIS TIME TO NORMAL OR ABOVE NORMAL
LEVELS.
&&
.AVIATION...03/18Z
HIGH CLOUDS INCREASING THE THICKENING AHEAD OF STORM SYSTEM
APPROACHING FROM THE WEST. EXPECT CIGS TO LOWER FROM FL150 TO AROUND
FL090-1100 BY 00Z...BUT WITH VFR CONDITIONS PREVAILING THROUGH THAT
TIME. SHOWERS AND ISOLATED/WIDELY SCATTERED THUNDERSTORMS EXPECTED
TO DEVELOP ACROSS EASTERN NEBR/WESTERN IA LATER THIS AFTERNOON AND
MOVE EASTWARD ACROSS THE AREA TONIGHT...BEGINNING AROUND OR SHORTLY
BEFORE 00Z AT KFOD AND KDSM AND BY AROUND SUNSET AT THE REMAINING
SITES. IT APPEARS PRECIP WILL BE WIDESPREAD AND PROLONGED
OVERNIGHT...WITH PREVAILING MVFR OR LOWER CONDITIONS LIKELY FROM
AROUND 02-04Z THROUGH AT LEAST SUNRISE SATURDAY AND QUITE POSSIBLY
TO THE END OF THE PERIOD...ALTHOUGH PRECIP WILL BE DECREASING AFTER
12Z. DUE TO PROLONGED NATURE OF PRECIP EVENT AND DIFFICULTY IN
PINNING DOWN LOCATIONS WHERE PERIODS OF HEAVIER RAIN/IFR OR LOWER
CONDITIONS WILL BE MOST LIKELY...HAVE OPTED TO INDICATE STEADILY
WORSENING CONDITIONS AT ALL TAF SITES AFTER 00Z WITH PREVAILING MVFR
CONTINUING THROUGH THE TAF PERIOD. BY 00Z TAF UPDATE SHOULD HAVE A
BETTER IDEA ON MORE PRECISE TIMING/LOCATION OF HEAVIER RAINS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/AVIATION...LEE
LONG TERM...COGIL
[top]
000
FXUS63 KDVN 032000
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
300 PM CDT FRI JUL 3 2009
.SYNOPSIS...
12Z UPPER AIR SHOWS A RIDGE OVER THE CENTRAL CONUS WITH A STRONG
SHORTWAVE LEAVING THE ROCKIES. A DECAYING LLJ HELPED FIRE AN MCS
OVER THE PLAINS WHICH IS MOVING THROUGH MISSOURI PER RADARS. 18Z SFC
ANALYSIS SHOWS LEE CYCLOGENESIS HAS OCCURRED IN WESTERN NEBRASKA AND
EASTERN COLORADO. A LEADING SFC WAVE OVER NORTHERN KANSAS HAD A WARM
FRONT RUNNING FROM CENTRAL KANSAS SOUTH INTO OKLAHOMA. WAA HAS
CREATED STRONG PRESSURE FALLS AT KCNK INDICATING AN EASTWARD
MOVEMENT OF THE SYSTEM. MOISTURE IS PLENTIFUL WITH THE SYSTEM...
EVIDENT BY MID 60 DEW POINTS AT THE SFC AND LOW TEEN DEW POINTS AT
H85.
&&
.SHORT TERM...TONIGHT AND SATURDAY...
THE QUESTION IS NOT IF IT WILL RAIN BUT HOW MUCH. SIGNALS ARE
CONSISTENT FOR A WIDESPREAD RAIN EVENT STARTING TONIGHT AND
CONTINUING INTO SATURDAY. PRECIP TO DEVELOP/MOVE INTO THE AREA THIS
EVENING WITH THE MAIN PRECIP RUNNING FROM 06-18Z AS THE LLJ SHIFTS
EASTWARD AND INCREASES TO NEAR 40 KNOTS. TSRA WITH LOCALLY HEAVY
RAINFALL IS A GIVEN ACROSS THE SOUTH THIRD AND HAVE GONE WITH THE
HIGHEST POPS THERE. MAINLY STRATIFORM RAIN EXPECTED OVER THE
REMAINDER OF THE CWFA BUT SOME ISOLATED TSRA MAY OCCUR OVER THE
MIDDLE THIRD OF THE CWFA.
ALL MODELS SHOW A RESPECTABLE DEFORMATION ZONE SETTING UP ACROSS THE
CWFA ON SATURDAY. THIS WILL PROLONG THE CLOUDS AND RAIN FOR MUCH OF
THE DAY. AS A RESULT...HAVE DROPPED MAX TEMPERATURES CONSIDERABLY
FOR SATURDAY. IT IS CONCEIVABLE THAT THE NORTH HALF OF THE CWFA MAY
STRUGGLE TO REACH 70 ON SATURDAY. HEAVIEST RAIN TO FALL OVER THE
SOUTHERN THIRD WHERE AROUND 1.5 INCHES SHOULD BE SEEN. LOCALLY
HIGHER AMOUNTS ABOVE 2 INCHES ARE POSSIBLE. CONSIDERED A WATCH BUT
FLASH FLOOD GUIDANCE IS AT LEAST 2.5 INCHES FOR 1 AND 3 HR AMOUNTS.
NUISANCE FLOODING WILL LIKELY BE SEEN IN SOME AREAS. ..08..
.LONG TERM...SATURDAY NIGHT THROUGH NEXT FRIDAY...
...QUIET...SEASONAL TEMPERATURES AND DRY INTO WEDNESDAY...THEN
BECOMING HOT AND MUGGY...
OVERALL INITIALIZATION AND VERIFICATION OF SOLUTION SUITE AVERAGE
TODAY WITH MAIN ISSUE CONVECTION INITIATION FROM ENERGY RIDING OVER
UPPER RIDGE SITUATED IN INTER MOUNTAIN REGION. HI-RES ECMWF AND GFS
LARGE SCALE GUIDANCE USED SINCE VERIFIES BEST ON MOISTURE AND RUN TO
RUN VARIANCE WITH LITTLE SENSIBLE DIFFERENCE SINCE ENTIRE AREA UNDER
SURFACE AND UPPER AIR RIDGING.
SATURDAY NIGHT...KEPT SLIGHT CHANCE POPS IN EVENING SOUTH 2/3 FOR
LINGERING LIGHT SHOWERS FROM DECAYING WRAP AROUND DEFORMATION ZONE.
THEN CLEARING MID TO LATE EVENING ON AS WEAK HIGH PRESSURE MOVES IN.
AREAS OF EARLIER MODERATE TO HEAVY RAINFALL...CLEARING SKIES AND
LIGHT WINDS TOWARD DAYBREAK...A FAVORABLE SETUP FOR PATCHY FOG
REMAINS. LIGHT NW WINDS AND SUBSIDENCE SHOULD MITIGATE HEAVY FOG
POTENTIAL. PASS TO LATER SHIFTS TO CONSIDER ADDING IN FORECAST NEXT
12-24 HOURS. MINS WENT ON LOW SIDE WITH VERY FAVORABLE RADIATIONAL
COOLING CRITERIA OUTLINED WITH LOCAL TOOLS SUPPORTING SOME MID 50S
POSSIBLE NORTH OF I-80 FOR SUBSEQUENT SHIFTS.
SUNDAY THROUGH TUESDAY...NW FLOW AND WEAK SURFACE HIGH PRESSURE
SUPPORTS DRY WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES WITH
MODERATE HUMIDITY LEVELS. HIGHS 79 TO 85F DEGREES WITH A DEGREE OR
TWO WARMING EACH DAY. MINS...WITH LIGHT WINDS AND FAIR SKIES...
MAINLY IN UPPER 50S TO LOWER 60S. MINS POSSIBLY STILL A FEW DEGREES
TOO MILD IN LOW LYING LOCATIONS FROM RADIATIONAL COOLING AND MODERATE
DEWPOINTS AND CLEAR SKIES.
WEDNESDAY THROUGH FRIDAY...WARMER WITH ABOVE NORMAL TEMPERATURES AND
HUMID TO VERY HUMID CONDITIONS AS UPPER LEVEL HIGH COMBINED WITH
SOUTH LOW LEVEL WINDS BRING IN WARMER...MORE HUMID AIR FROM SOUTHERN
PLAINS. HIGHS IN UPPER 80S RISING INTO LOWER 90S INDICATED. HEAT
INDEX VALUES TO APPROACH 100F THURSDAY AND FRIDAY DURING AFTERNOON
HOURS. AREA DEWPOINTS MAY STILL BE A FEW DEGREES TOO LOW WITH 70+
VALUES SUGGESTED FOR VERY HUMID CONDITIONS. ADDED SLIGHT CHANCE POPS
DAY 7 AS SUMMERTIME CONVECTIVE SYSTEM POSSIBLE AS NEXT FRONT
APPROACHES. IF A MCS DOES ARRIVE...LIKELY TO PRODUCE SOME SIGNIFICANT
WINDS DUE TO HIGH INSTABILITY VALUES. ..NICHOLS..
&&
.AVIATION...
VFR WX THROUGH 04/00Z. AFT 04/00Z CONDITIONS TO DETERIORATE TO MVFR
AND POSSIBLY IFR VSBYS/CIGS. STRONG SYSTEM TO PASS JUST SOUTH OF
KBRL PROVIDING TSRA. KBRL TO HAVE THE HIGHEST IMPACT AND HAVE
VSBYS/CIGS DROPPING TO 2SM AND 1KFT JUST PRIOR TO SUNRISE WITH TSRA
LIKELY BUT HAVE ONLY GONE WITH VCTS FOR NOW. KCID/KMLI MAY OR MAY
NOT SEE TSRA BUT HAVE INCLUDED CB WORDING FOR CLDS. BOTH SITES
SHOULD SEE 1-2KFT CIGS PRIOR TO SUNRISE WITH 3-5SM...POSSIBLY WORSE
VSBYS. KDBQ THE LEAST AFFECTED BUT WILL SEE 3-5SM VSBY AND 2KFT
CIGS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE
IL...NONE
MO...NONE
&&
$$
08/NICHOLS
000
FXUS63 KDMX 031744 AAB
AFDDMX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
1244 PM CDT FRI JUL 3 2009
.UPDATED AVIATION DISCUSSION...
.SHORT TERM...
INCREASINGLY ACTIVE DAY TODAY...AFTER SEVERAL QUIET DAYS WITH DECENT
SHORTWAVE TOPPING CENTRAL US RIDGE...AND PUSHING EAST SOUTHEAST
ACROSS THE CWA TODAY INTO TONIGHT. ASSOCIATED SURFACE LOW CURRENTLY
DEVELOPING ALONG THE FRONT RANGE OF THE ROCKIES...WITH SFC LOW
EXPECTED TO TRACK INTO CNTRL NE/KS BY LATE THIS AFTERNOON. INVERTED
TROF FEATURE TO JUT INTO ERN NE...WITH A WARM FRONT MOVING
NORTHEASTWARD INTO THE WESTERN CENTRAL CWA BY THIS AFTERNOON. DECENT
LIFT IN WAA AREA ALONG AND BEHIND THE FRONT. ISENTROPIC ANALYSIS
SUGGESTING BEST LIFT ACROSS THE WEST CENTRAL CWA BY 21Z TO
00Z...WITH AMPLE MOISTURE. THEREFORE HAVE INCREASED POPS INTO THE
LIKELY TO CATEGORICAL RANGE. SOME WEAK MUCAPE ANALYZED BY LATE THIS
AFTERNOON...WITH SOUNDINGS SHOWING A VERY SMALL AMOUNT OF SFC BASED
CAPE. THEREFORE STUCK WITH MAINLY SHOWER AND ISOLATED THUNDER
WORDING. INCREASED TEMPS A FEW DEGREES ACROSS THE EAST...WHERE WILL
TAKE A LITTLE LONGER FOR CLOUD COVER/PRECIP TO MOVE INTO THE AREA SO
SHOULD SEE BETTER CHANCE TO WARM UP. WENT COOLEST ACROSS THE WEST
WITH CLOUDS/PRECIP ALREADY EXPECTED TO MOVE IN BY EARLY AFTERNOON.
.LONG TERM...
ALL OF THE SIG WX IS IN THE FRONT END OF THIS FCST SYS IS JUST A
LITTLE SLOWER THAN THINKING WAS THE PAST COUPLE DAYS...BUT THINGS
ARE ON TRACK. ISENT ANAL SHOWS STRONG LIFT ACRS THE CWA WITH 100 TO
150 MB LFT ON THE 310 ISENT SFC FOR EXAMPLE. MDLS HAVE COME
TOGETHER WITH SOLNS FOR THE MOST PART. NAM PCPN TTLS SEEM TOO
HIGH...BUT MAY WELL REPRESENT THE MAX VALUES. POSITIONING OF THE
AXIS NOT ALL THAT DIF WITH THE FIM/EC SOLNS A LTL FARTHER N THAN
OTHERS...BUT OVR ALL DIF NOT THAT GREAT. CAT POPS LOOK GOOD FOR
TNGT AND LOOK FOR A SYS TTL PCPN IN THE 1/2 - 1 1/2 INCH RANGE OVR
THE CWA. SVR POT IS LOW WITH CAPE QUITE LMTD. DYNAMICS ARE
SUFFICIENT TO GET A DECENT MCS GOING AND THERE IS SOME POSSIBILITY
OF AN UPSCALED MCS CLOSER TO THE FRONT DURG THE EVE HRS. AS FAR AS
FLOODING ISSUES ARE CONCERNED...FEEL THE LONGER DRAWN OUT PD OF PCPN
WILL KEEP THINGS WELL BLO FFG VALUES. CUR 6 HR FFG VALUES ACRS THE
CWA RANGE FROM 2 1/2 TO 5 1/2 INCHES AND DO NOT XPCT TO SEE THOSE
EXCEEDED. PCPN SLIDES SEWD AND SHOULD PRETTY MUCH BE OUT OF THE CWA
BY AFTN WITH ONLY ISOLD IN THE SE. GENERALLY DRY AFT THAT WELL INTO
NXT WK WITH A GRADU WRMG TREND.
&&
.AVIATION...03/18Z
HIGH CLOUDS INCREASING THE THICKENING AHEAD OF STORM SYSTEM
APPROACHING FROM THE WEST. EXPECT CIGS TO LOWER FROM FL150 TO AROUND
FL090-1100 BY 00Z...BUT WITH VFR CONDITIONS PREVAILING THROUGH THAT
TIME. SHOWERS AND ISOLATED/WIDELY SCATTERED THUNDERSTORMS EXPECTED
TO DEVELOP ACROSS EASTERN NEBR/WESTERN IA LATER THIS AFTERNOON AND
MOVE EASTWARD ACROSS THE AREA TONIGHT...BEGINNING AROUND OR SHORTLY
BEFORE 00Z AT KFOD AND KDSM AND BY AROUND SUNSET AT THE REMAINING
SITES. IT APPEARS PRECIP WILL BE WIDESPREAD AND PROLONGED
OVERNIGHT...WITH PREVAILING MVFR OR LOWER CONDITIONS LIKELY FROM
AROUND 02-04Z THROUGH AT LEAST SUNRISE SATURDAY AND QUITE POSSIBLY
TO THE END OF THE PERIOD...ALTHOUGH PRECIP WILL BE DECREASING AFTER
12Z. DUE TO PROLONGED NATURE OF PRECIP EVENT AND DIFFICULTY IN
PINNING DOWN LOCATIONS WHERE PREIODS OF HEAVIER RAIN/IFR OR LOWER
CONDITINOS WILL BE MOST LIKELY...HAVE OPTED TO INDICATE STEADILY
WORSENING CONDITIONS AT ALL TAF SITES AFTER 00Z WITH PREVAILING MVFR
CONTINUING THROUGH THE TAF PERIOD. BY 00Z TAF UPDATE SHOULD HAVE A
BETTER IDEA ON MORE PRECISE TIMING/LOCATION OF HEAVIER RAINS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MJA
AVIATION...LEE
LONG TERM...MS JUL 09
000
FXUS63 KDMX 031137
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
635 AM CDT FRI JUL 3 2009
.UPDATED FOR THE 12Z AVIATION DISCUSSION...
.SHORT TERM...
INCREASINGLY ACTIVE DAY TODAY...AFTER SEVERAL QUIET DAYS WITH DECENT
SHORTWAVE TOPPING CENTRAL US RIDGE...AND PUSHING EAST SOUTHEAST
ACROSS THE CWA TODAY INTO TONIGHT. ASSOCIATED SURFACE LOW CURRENTLY
DEVELOPING ALONG THE FRONT RANGE OF THE ROCKIES...WITH SFC LOW
EXPECTED TO TRACK INTO CNTRL NE/KS BY LATE THIS AFTERNOON. INVERTED
TROF FEATURE TO JUT INTO ERN NE...WITH A WARM FRONT MOVING
NORTHEASTWARD INTO THE WESTERN CENTRAL CWA BY THIS AFTERNOON. DECENT
LIFT IN WAA AREA ALONG AND BEHIND THE FRONT. ISENTROPIC ANALYSIS
SUGGESTING BEST LIFT ACROSS THE WEST CENTRAL CWA BY 21Z TO
00Z...WITH AMPLE MOISTURE. THEREFORE HAVE INCREASED POPS INTO THE
LIKELY TO CATEGORICAL RANGE. SOME WEAK MUCAPE ANALYZED BY LATE THIS
AFTERNOON...WITH SOUNDINGS SHOWING A VERY SMALL AMOUNT OF SFC BASED
CAPE. THEREFORE STUCK WITH MAINLY SHOWER AND ISOLATED THUNDER
WORDING. INCREASED TEMPS A FEW DEGREES ACROSS THE EAST...WHERE WILL
TAKE A LITTLE LONGER FOR CLOUD COVER/PRECIP TO MOVE INTO THE AREA SO
SHOULD SEE BETTER CHANCE TO WARM UP. WENT COOLEST ACROSS THE WEST
WITH CLOUDS/PRECIP ALREADY EXPECTED TO MOVE IN BY EARLY AFTERNOON.
.LONG TERM...
ALL OF THE SIG WX IS IN THE FRONT END OF THIS FCST SYS IS JUST A
LITTLE SLOWER THAN THINKING WAS THE PAST COUPLE DAYS...BUT THINGS
ARE ON TRACK. ISENT ANAL SHOWS STRONG LIFT ACRS THE CWA WITH 100 TO
150 MB LFT ON THE 310 ISENT SFC FOR EXAMPLE. MDLS HAVE COME
TOGETHER WITH SOLNS FOR THE MOST PART. NAM PCPN TTLS SEEM TOO
HIGH...BUT MAY WELL REPRESENT THE MAX VALUES. POSITIONING OF THE
AXIS NOT ALL THAT DIF WITH THE FIM/EC SOLNS A LTL FARTHER N THAN
OTHERS...BUT OVR ALL DIF NOT THAT GREAT. CAT POPS LOOK GOOD FOR
TNGT AND LOOK FOR A SYS TTL PCPN IN THE 1/2 - 1 1/2 INCH RANGE OVR
THE CWA. SVR POT IS LOW WITH CAPE QUITE LMTD. DYNAMICS ARE
SUFFICIENT TO GET A DECENT MCS GOING AND THERE IS SOME POSSIBILITY
OF AN UPSCALED MCS CLOSER TO THE FRONT DURG THE EVE HRS. AS FAR AS
FLOODING ISSUES ARE CONCERNED...FEEL THE LONGER DRAWN OUT PD OF PCPN
WILL KEEP THINGS WELL BLO FFG VALUES. CUR 6 HR FFG VALUES ACRS THE
CWA RANGE FROM 2 1/2 TO 5 1/2 INCHES AND DO NOT XPCT TO SEE THOSE
EXCEEDED. PCPN SLIDES SEWD AND SHOULD PRETTY MUCH BE OUT OF THE CWA
BY AFTN WITH ONLY ISOLD IN THE SE. GENERALLY DRY AFT THAT WELL INTO
NXT WK WITH A GRADU WRMG TREND.
&&
.AVIATION...03/12Z
HIGH CIRRUS SHIELD ADVANCING ACROSS THE CWA AHEAD OF AN UPPER LEVEL
DISTURBANCE TRAVELING ATOP THE CENTRAL US RIDGE. SYSTEM TO MOVE
EASTWARD INTO IOWA LATER TODAY INTO TONIGHT...WITH CIGS LOWERING TO
LOWER VFR TO MVFR TOWARD THIS AFTERNOON INTO TONIGHT. SHOWERS AND
ISOLATED THUNDERSTORMS ACROSS CENTRAL NEBRASKA TO SPREAD EASTWARD
INTO IOWA BY THIS AFTERNOON AND LINGER THROUGH TONIGHT. WINDS TO
BECOME SOUTHERLY AS A WARM FRONT LIFTS THROUGH THE STATE.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MJA
AVIATION...MJA
LONG TERM...MS JUL 09
000
FXUS63 KDMX 031012 CCA
AFDDMX
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE DES MOINES IA
512 AM CDT FRI JUL 3 2009
.SHORT TERM...
INCREASINGLY ACTIVE DAY TODAY...AFTER SEVERAL QUIET DAYS WITH DECENT
SHORTWAVE TOPPING CENTRAL US RIDGE...AND PUSHING EAST SOUTHEAST
ACROSS THE CWA TODAY INTO TONIGHT. ASSOCIATED SURFACE LOW CURRENTLY
DEVELOPING ALONG THE FRONT RANGE OF THE ROCKIES...WITH SFC LOW
EXPECTED TO TRACK INTO CNTRL NE/KS BY LATE THIS AFTERNOON. INVERTED
TROF FEATURE TO JUT INTO ERN NE...WITH A WARM FRONT MOVING
NORTHEASTWARD INTO THE WESTERN CENTRAL CWA BY THIS AFTERNOON. DECENT
LIFT IN WAA AREA ALONG AND BEHIND THE FRONT. ISENTROPIC ANALYSIS
SUGGESTING BEST LIFT ACROSS THE WEST CENTRAL CWA BY 21Z TO
00Z...WITH AMPLE MOISTURE. THEREFORE HAVE INCREASED POPS INTO THE
LIKELY TO CATEGORICAL RANGE. SOME WEAK MUCAPE ANALYZED BY LATE THIS
AFTERNOON...WITH SOUNDINGS SHOWING A VERY SMALL AMOUNT OF SFC BASED
CAPE. THEREFORE STUCK WITH MAINLY SHOWER AND ISOLATED THUNDER
WORDING. INCREASED TEMPS A FEW DEGREES ACROSS THE EAST...WHERE WILL
TAKE A LITTLE LONGER FOR CLOUD COVER/PRECIP TO MOVE INTO THE AREA SO
SHOULD SEE BETTER CHANCE TO WARM UP. WENT COOLEST ACROSS THE WEST
WITH CLOUDS/PRECIP ALREADY EXPECTED TO MOVE IN BY EARLY AFTERNOON.
.LONG TERM...
ALL OF THE SIG WX IS IN THE FRONT END OF THIS FCST SYS IS JUST A
LITTLE SLOWER THAN THINKING WAS THE PAST COUPLE DAYS...BUT THINGS
ARE ON TRACK. ISENT ANAL SHOWS STRONG LIFT ACRS THE CWA WITH 100 TO
150 MB LFT ON THE 310 ISENT SFC FOR EXAMPLE. MDLS HAVE COME
TOGETHER WITH SOLNS FOR THE MOST PART. NAM PCPN TTLS SEEM TOO
HIGH...BUT MAY WELL REPRESENT THE MAX VALUES. POSITIONING OF THE
AXIS NOT ALL THAT DIF WITH THE FIM/EC SOLNS A LTL FARTHER N THAN
OTHERS...BUT OVR ALL DIF NOT THAT GREAT. CAT POPS LOOK GOOD FOR
TNGT AND LOOK FOR A SYS TTL PCPN IN THE 1/2 - 1 1/2 INCH RANGE OVR
THE CWA. SVR POT IS LOW WITH CAPE QUITE LMTD. DYNAMICS ARE
SUFFICIENT TO GET A DECENT MCS GOING AND THERE IS SOME POSSIBILITY
OF AN UPSCALED MCS CLOSER TO THE FRONT DURG THE EVE HRS. AS FAR AS
FLOODING ISSUES ARE CONCERNED...FEEL THE LONGER DRAWN OUT PD OF PCPN
WILL KEEP THINGS WELL BLO FFG VALUES. CUR 6 HR FFG VALUES ACRS THE
CWA RANGE FROM 2 1/2 TO 5 1/2 INCHES AND DON`T XPCT TO SEE THOSE
EXCEDED. PCPN SLIDES SEWD AND SHOULD PRETTY MUCH BE OUT OF THE CWA
BY AFTN WITH ONLY ISOLD IN THE SE. GENERALLY DRY AFT THAT WELL INTO
NXT WK WITH A GRADU WRMG TREND.
&&
.AVIATION...03/06Z
VFR CONDITIONS CONTINUE THROUGH THE FIRST 18 HOURS OF TAF PERIOD FOR
THE MAJORITY OF THE TAF SITES. WITH SURFACE LOW AND SHORTWAVE
ADVANCING TOWARD THE FORECAST AREA DURING THE DAY ON
FRIDAY...CONTINUED TO KEEP INCREASING CLOUDINESS AOA 5000FT THROUGH
THE AFTERNOON HOURS FRIDAY. THETA-E ADVECTION IS EVIDENT ACROSS THE
SOUTHWEST HALF OF THE STATE BY 00Z SAT AND CONTINUES TO SPREAD
EASTWARD BY 06Z SAT. CONFIDENT ENOUGH TO MENTION THUNDER FOR FOD
WITH MVFR CIG AND VIS TOWARD THE END OF TAF PERIOD. HOWEVER...WITH
THE AMOUNT OF QPF THE LATEST MODEL RUNS ARE FORECASTING...MAY SEE
SOME LOWER VIS BY 06Z SAT. SO CONFIDENCE WAS LOW WITH MENTIONING
IFR/LIFR CONDITIONS ATTM. SIMILAR SITUATION WITH DSM AND OTM...BUT
SHIFTED LATER IN TIME FRAME. MENTIONED VCTS TOWARDS END OF TAF
PERIOD FOR THESE TWO SITES...BUT CONFIDENCE WAS LOW IN TIMING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MJA
AVIATION...PODRAZIK
LONG TERM...MS JUL 09
000
FXUS63 KDMX 030838 AAB
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
330 AM CDT FRI JUL 3 2009
.SHORT TERM...
INCREASINGLY ACTIVE DAY TODAY...AFTER SEVERAL QUIET DAYS WITH DECENT
SHORTWAVE TOPPING CENTRAL US RIDGE...AND PUSHING EAST SOUTHEAST
ACROSS THE CWA TODAY INTO TONIGHT. ASSOCIATED SURFACE LOW CURRENTLY
DEVELOPING ALONG THE FRONT RANGE OF THE ROCKIES...WITH SFC LOW
EXPECTED TO TRACK INTO CNTRL NE/KS BY LATE THIS AFTERNOON. INVERTED
TROF FEATURE TO JUT INTO ERN NE...WITH A WARM FRONT MOVING
NORTHEASTWARD INTO THE WESTERN CENTRAL CWA BY THIS AFTERNOON. DECENT
LIFT IN WAA AREA ALONG AND BEHIND THE FRONT. ISENTROPIC ANALYSIS
SUGGESTING BEST LIFT ACROSS THE WEST CENTRAL CWA BY 21Z TO
00Z...WITH AMPLE MOISTURE. THEREFORE HAVE INCREASED POPS INTO THE
LIKELY TO CATEGORICAL RANGE. SOME WEAK MUCAPE ANALYZED BY LATE THIS
AFTERNOON...WITH SOUNDINGS SHOWING A VERY SMALL AMOUNT OF SFC BASED
CAPE. THEREFORE STUCK WITH MAINLY SHOWER AND ISOLATED THUNDER
WORDING. INCREASED TEMPS A FEW DEGREES ACROSS THE WEST...WHERE WILL
TAKE A LITTLE LONGER FOR CLOUD COVER/PRECIP TO MOVE INTO THE AREA SO
SHOULD SEE BETTER CHANCE TO WARM UP. WENT COOLEST ACROSS THE WEST
WITH CLOUDS/PRECIP ALREADY EXPECTED TO MOVE IN BY EARLY AFTERNOON.
.LONG TERM...
ALL OF THE SIG WX IS IN THE FRONT END OF THIS FCST SYS IS JUST A
LITTLE SLOWER THAN THINKING WAS THE PAST COUPLE DAYS...BUT THINGS
ARE ON TRACK. ISENT ANAL SHOWS STRONG LIFT ACRS THE CWA WITH 100 TO
150 MB LFT ON THE 310 ISENT SFC FOR EXAMPLE. MDLS HAVE COME
TOGETHER WITH SOLNS FOR THE MOST PART. NAM PCPN TTLS SEEM TOO
HIGH...BUT MAY WELL REPRESENT THE MAX VALUES. POSITIONING OF THE
AXIS NOT ALL THAT DIF WITH THE FIM/EC SOLNS A LTL FARTHER N THAN
OTHERS...BUT OVR ALL DIF NOT THAT GREAT. CAT POPS LOOK GOOD FOR
TNGT AND LOOK FOR A SYS TTL PCPN IN THE 1/2 - 1 1/2 INCH RANGE OVR
THE CWA. SVR POT IS LOW WITH CAPE QUITE LMTD. DYNAMICS ARE
SUFFICIENT TO GET A DECENT MCS GOING AND THERE IS SOME POSSIBILITY
OF AN UPSCALED MCS CLOSER TO THE FRONT DURG THE EVE HRS. AS FAR AS
FLOODING ISSUES ARE CONCERNED...FEEL THE LONGER DRAWN OUT PD OF PCPN
WILL KEEP THINGS WELL BLO FFG VALUES. CUR 6 HR FFG VALUES ACRS THE
CWA RANGE FROM 2 1/2 TO 5 1/2 INCHES AND DON`T XPCT TO SEE THOSE
EXCEDED. PCPN SLIDES SEWD AND SHOULD PRETTY MUCH BE OUT OF THE CWA
BY AFTN WITH ONLY ISOLD IN THE SE. GENERALLY DRY AFT THAT WELL INTO
NXT WK WITH A GRADU WRMG TREND.
&&
.AVIATION...03/06Z
VFR CONDITIONS CONTINUE THROUGH THE FIRST 18 HOURS OF TAF PERIOD FOR
THE MAJORITY OF THE TAF SITES. WITH SURFACE LOW AND SHORTWAVE
ADVANCING TOWARD THE FORECAST AREA DURING THE DAY ON
FRIDAY...CONTINUED TO KEEP INCREASING CLOUDINESS AOA 5000FT THROUGH
THE AFTERNOON HOURS FRIDAY. THETA-E ADVECTION IS EVIDENT ACROSS THE
SOUTHWEST HALF OF THE STATE BY 00Z SAT AND CONTINUES TO SPREAD
EASTWARD BY 06Z SAT. CONFIDENT ENOUGH TO MENTION THUNDER FOR FOD
WITH MVFR CIG AND VIS TOWARD THE END OF TAF PERIOD. HOWEVER...WITH
THE AMOUNT OF QPF THE LATEST MODEL RUNS ARE FORECASTING...MAY SEE
SOME LOWER VIS BY 06Z SAT. SO CONFIDENCE WAS LOW WITH MENTIONING
IFR/LIFR CONDITIONS ATTM. SIMILAR SITUATION WITH DSM AND OTM...BUT
SHIFTED LATER IN TIME FRAME. MENTIONED VCTS TOWARDS END OF TAF
PERIOD FOR THESE TWO SITES...BUT CONFIDENCE WAS LOW IN TIMING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MJA
AVIATION...PODRAZIK
LONG TERM...MS JUL 09
000
FXUS63 KDVN 030836
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
336 AM CDT FRI JUL 3 2009
.SYNOPSIS...
LOW PRESSURE EXPECTED TO MOVE OUT OF THE HIGH PLAINS TODAY AND INTO
NW MO TONIGHT AND THEN TO SOUTHERN IL ON SATURDAY. THIS SHOULD
SPREAD RAIN AND SOME THUNDERSTORMS ACROSS THE DVN CWA ESPECIALLY
TONIGHT AND INTO THE 4TH OF JULY. LATER NEXT WEEK HOT DOME BUILDS
INTO THE MIDWEST RETURNING TEMPERATURES INTO THE 90S.
&&
.SHORT TERM...TODAY AND TONIGHT...
OPERATIONAL MODELS SIMILAR IN BRINGING LOW PRESSURE OUT OF THE HIGH
PLAINS TODAY AND INTO NW MO TONIGHT. IN THE MEANTIME WARM FRONT
SHOULD BE LIFTING INTO NORTHERN MO TONIGHT AS LOW LEVEL JET
STRENGTHENS. MODELS AGREE IN KEEPING THE CWA DRY TODAY AS DRY AIR IN
PLACE WITH SURFACE DEWPOINTS IN THE 50S. BUT RAIN SHOULD SPREAD INTO
THE WESTERN CWA THIS EVENING AND OVER ALL OF THE AREA TONIGHT. HAVE
INCREASED POPS FOR TONIGHT INTO AT LEAST THE 70 TO 80 PERCENT RANGE.
MODELS INDICATING STRONG FRONTOGENETICAL FORCING ACROSS PORTIONS OF
THE CWA. THETA-E ADVECTION WOULD SUGGEST THE MAIN THUNDERSTORM
ACTIVITY WILL BE FROM ABOUT HIGHWAY 34 SOUTHWARD...WITH RAIN AND
ISOLATED THUNDERSTORMS OVER OUR NORTHERN COUNTIES. 00Z ECMWF IS THE
ONLY MODEL THAT EMPHASIZES THE HEAVIEST QPF NORTH OF INTERSTATE 80.
WILL SIDE WITH OTHER MODELS SUGGESTING THE HIGHER QPF WILL BE ALONG
AND SOUTH OF HIGHWAY 34...CLOSER TO THE WARM FRONT AND HIGHER
DEWPOINTS. THIS AGREES WITH HPC GUIDANCE. THE 00Z 4.0 KM WRF-NMM
MODEL WHICH HAS DONE QUITE WELL WITH CONVECTION THE PAST SEVERAL
EVENTS ALSO INDICATES THE MAIN THUNDERSTORM AREA TO BE OVER OUR
SOUTHERN CWA. CURRENTLY THUNDERSTORM ACTIVITY HAS INCREASED ALONG
WARM FRONT IN KS AND EXPECT THIS TREND TO CONTINUE.
..HAASE..
.LONG TERM...SATURDAY THROUGH NEXT THURSDAY...
THE MAIN FORECAST CONCERN AFTER TONIGHT WILL BE THE CONTINUING
CHANCES FOR PRECIPITATION INTO THE FIRST PART OF SATURDAY. AFTER THE
WEEKEND...THE FOCUS SHIFTS TO A WARMING TREND AS WE GO THROUGH NEXT
WEEK.
AFOREMENTIONED CONCERNS REGARDING PLACEMENT OF MAIN PRECIPITATION
AXIS CONTINUE INTO THE SATURDAY TIMEFRAME. HAVE SPREAD PRECIPITATION
CHANCES FURTHER NORTH FOR THE DAYTIME HOURS ON SATURDAY...BUT
CONTINUED TO FOCUS HIGHEST PRECIPITATION CHANCES AND AMOUNTS MAINLY
SOUTH OF INTERSTATE 80. THE MID LEVEL FRONT IS FORECAST TO BE
POSITIONED WITHIN THE FORECAST AREA THROUGH THE SATURDAY
MORNING...AS THE SURFACE LOW HEADS SOUTHEAST FROM NORTHERN MISSOURI
TOWARD SOUTHEAST MISSOURI/SOUTHERN ILLINOIS. ALTHOUGH AN ISOLATED
THUNDERSTORM IS NOT OUT OF THE QUESTION...THE BETTER CHANCES FOR
THUNDERSTORM ACTIVITY WILL ALSO BE SOUTH OF INTERSTATE 80...IN
CLOSER PROXIMITY TO THE SURFACE LOW.
PRECIPITATION CHANCES TAPER OFF RATHER QUICKLY FOR SATURDAY
EVENING...WITH THE REMAINDER OF THE FORECAST DRY AT THIS TIME.
TEMPERATURES ARE ALSO A CHALLENGE ON SATURDAY...AS THEY WILL BE
GREATLY INFLUENCED BY THE ANTICIPATED CLOUD COVER AND PRECIPITATION.
TEMPERATURES IN THE 70S ARE EXPECTED FOR DAYTIME HIGHS ON
SATURDAY...WITH UPPER 50S/LOWER 60S TO FOLLOW FOR SATURDAY NIGHT.
A WARMING TREND WILL GET UNDERWAY AS NEXT WEEK PROGRESSES.
TEMPERATURES ARE EXPECTED TO MODERATE BACK TO AROUND NORMAL BY
MIDWEEK...WITH ABOVE NORMAL TEMPERATURES LOOKING TO BE A GOOD BET BY
LATE WEEK.
..STOFLET..
&&
.AVIATION...
VFR CONDITIONS TODAY WITH PATCHY MVFR BR 09-13Z. RAIN SPREADING INTO
EASTERN IA FROM WEST TO EAST THIS EVENING AND FRIDAY NIGHT. OCNL
MVFR IN RAIN. SCATTERED THUNDERSTORMS SOUTH OF INTERSTATE 80.
..HAASE..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
HAASE/STOFLET
000
FXUS63 KDMX 030500 AAB
AFDDMX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
1159 PM CDT THU JUL 2 2009
...UPDATED 03/06Z AVIATION DISCUSSION...
.SHORT TERM...
HIGH PRESSURE SETTLING ACROSS THE AREA WILL MAKE FOR A QUIET NIGHT.
CLOUDS THAT HAVE FORMED OVER THE EASTERN HALF OF THE STATE THIS
AFTERNOON WILL DISSIPATE AND MOVE AWAY AFTER SUNSET AND WINDS WILL
BECOME VERY LIGHT AND VARIABLE. SOME HIGH CLOUDS WILL MOVE INTO
WESTERN AND SOUTHWESTERN IOWA DURING THE EARLY MORNING
HOURS...OTHERWISE MOSTLY CLEAR SKIES WILL PREVAIL. THIS WILL LEAD TO
GOOD RADIATIONAL COOLING CONDITIONS ESPECIALLY IN OUR EASTERN AND
NORTHEASTERN COUNTIES. HAVE LOWERED MIN TEMPS TONIGHT ACROSS OUR
AREA...ESPECIALLY IN THE EAST AND NORTHEAST. HAVE ALSO REMOVED POPS
FOR LATE TONIGHT AS IT APPEARS PRECIP WILL NOT ENTER OUR AREA UNTIL
AFTER 12Z FRIDAY.
.LONG TERM...
SENSIBLE WEATHER PICKS UP ON FRIDAY INTO SATURDAY AS SHORTWAVE
SLIDES OVER RIDGE AXIS TO THE WEST. WL SEE INCREASING WAA THROUGH
THE DAY AS WINDS BECOME SOUTHEASTERLY AND THETA-E INCREASES. MODELS
DO HAVE SOME DIFFERENCE WITH NAM MUCH FARTHER NORTH THAN THE GFS OR
SREF. THE GEM AND ECMWF ARE SLOWER THAN ALL THE OTHER MODELS SO
THESE LEADS TO QUITE A BIT OF UNCERTAINTY REGARDING THE EVOLUTION OF
THIS SYSTEM. NEWEST 18Z NAM HAS COME IN A BIT FARTHER SOUTH AND
SLOWER THAN ITS 12Z COUNTERPART AND SO GIVES MORE CONFIDENCE TO THE
GFS/SREF SCENARIO. IN ALMOST ALL CASES...CAPE REMAINS IN CHECK WITH
VALUES GENERALLY UNDER 1000 J/KG. SHEAR IS QUITE GOOD...BUT MOST IF
NOT ALL INSTABILITY IS ELEVATED SO ANY REALIZATION OF THE SHEAR WILL
BE MINIMIZED. MAY STILL EEK OUT SOME SEVERE REPORTS BUT MOST LIKELY
THIS WILL BE CONFINED TO THE FAR SOUTHERN PORTIONS OF THE CWA. HAVE
GONE WITH LIKELY POPS ON FRIDAY AFTERNOON INTO FRIDAY NIGHT ACRS
MUCH OF THE SOUTHERN HALF OF THE CWA WHERE BEST WAA/THETA-E
ADVECTION OCCURS. LIKELY TO SEE SOME DECENT RAINFALL WITH PWATS IN
EXCESS OF 1.50" BY FRIDAY AFTERNOON AND MAY SEE SOME LOCALIZED HEAVY
AMOUNTS. OTHERWISE...TEMPS ON FRIDAY WILL BE INFLUENCED GREATLY BY
CLOUD COVER AND HOW QUICKLY RAINFALL MOVES INTO THE AREA. GIVEN THE
UNCERTAINTY...HAVE GENERALLY STAYED CLOSE TO MOS. WL SEE MOST OF
THE FORCING PASS BY EARLY SATURDAY...HOWEVER SOME LINGERING THREAT
WL REMAIN ON SATURDAY AS A SECONDARY SHORTWAVE PASSES OVER THE
STATE. THEREAFTER...WL SEE SFC RIDGING BUILD INTO THE REGION WITH
RELATIVELY COOL TEMPERATURES AND DRY CONDITIONS. UPPER RIDGING
BEGINS TO BUILD INTO THE MIDWEST NEXT WEEK AND ANTICIPATE A GRADUAL
WARMING TREND DURING THIS TIME. WITH JET AXIS SHIFTING TO THE NORTH
ALONG WITH THE STORM TRACK...LOOKS LIKE A DRY PERIOD AS WELL.
&&
.AVIATION...03/06Z
VFR CONDITIONS CONTINUE THROUGH THE FIRST 18 HOURS OF TAF PERIOD FOR
THE MAJORITY OF THE TAF SITES. WITH SURFACE LOW AND SHORTWAVE
ADVANCING TOWARD THE FORECAST AREA DURING THE DAY ON
FRIDAY...CONTINUED TO KEEP INCREASING CLOUDINESS AOA 5000FT THROUGH
THE AFTERNOON HOURS FRIDAY. THETA-E ADVECTION IS EVIDENT ACROSS THE
SOUTHWEST HALF OF THE STATE BY 00Z SAT AND CONTINUES TO SPREAD
EASTWARD BY 06Z SAT. CONFIDENT ENOUGH TO MENTION THUNDER FOR FOD
WITH MVFR CIG AND VIS TOWARD THE END OF TAF PERIOD. HOWEVER...WITH
THE AMOUNT OF QPF THE LATEST MODEL RUNS ARE FORECASTING...MAY SEE
SOME LOWER VIS BY 06Z SAT. SO CONFIDENCE WAS LOW WITH MENTIONING
IFR/LIFR CONDITIONS ATTM. SIMILAR SITUATION WITH DSM AND OTM...BUT
SHIFTED LATER IN TIME FRAME. MENTIONED VCTS TOWARDS END OF TAF
PERIOD FOR THESE TWO SITES...BUT CONFIDENCE WAS LOW IN TIMING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...LEE
AVIATION...PODRAZIK
LONG TERM...COGIL
000
FXUS63 KDMX 022351 AAA
AFDDMX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
650 PM CDT THU JUL 2 2009
.UPDATED 03/00Z AVIATION DISCUSSION...
.SHORT TERM...
HIGH PRESSURE SETTLING ACROSS THE AREA WILL MAKE FOR A QUIET NIGHT.
CLOUDS THAT HAVE FORMED OVER THE EASTERN HALF OF THE STATE THIS
AFTERNOON WILL DISSIPATE AND MOVE AWAY AFTER SUNSET AND WINDS WILL
BECOME VERY LIGHT AND VARIABLE. SOME HIGH CLOUDS WILL MOVE INTO
WESTERN AND SOUTHWESTERN IOWA DURING THE EARLY MORNING
HOURS...OTHERWISE MOSTLY CLEAR SKIES WILL PREVAIL. THIS WILL LEAD TO
GOOD RADIATIONAL COOLING CONDITIONS ESPECIALLY IN OUR EASTERN AND
NORTHEASTERN COUNTIES. HAVE LOWERED MIN TEMPS TONIGHT ACROSS OUR
AREA...ESPECIALLY IN THE EAST AND NORTHEAST. HAVE ALSO REMOVED POPS
FOR LATE TONIGHT AS IT APPEARS PRECIP WILL NOT ENTER OUR AREA UNTIL
AFTER 12Z FRIDAY.
.LONG TERM...
SENSIBLE WEATHER PICKS UP ON FRIDAY INTO SATURDAY AS SHORTWAVE
SLIDES OVER RIDGE AXIS TO THE WEST. WL SEE INCREASING WAA THROUGH
THE DAY AS WINDS BECOME SOUTHEASTERLY AND THETA-E INCREASES. MODELS
DO HAVE SOME DIFFERENCE WITH NAM MUCH FARTHER NORTH THAN THE GFS OR
SREF. THE GEM AND ECMWF ARE SLOWER THAN ALL THE OTHER MODELS SO
THESE LEADS TO QUITE A BIT OF UNCERTAINTY REGARDING THE EVOLUTION OF
THIS SYSTEM. NEWEST 18Z NAM HAS COME IN A BIT FARTHER SOUTH AND
SLOWER THAN ITS 12Z COUNTERPART AND SO GIVES MORE CONFIDENCE TO THE
GFS/SREF SCENARIO. IN ALMOST ALL CASES...CAPE REMAINS IN CHECK WITH
VALUES GENERALLY UNDER 1000 J/KG. SHEAR IS QUITE GOOD...BUT MOST IF
NOT ALL INSTABILITY IS ELEVATED SO ANY REALIZATION OF THE SHEAR WILL
BE MINIMIZED. MAY STILL EEK OUT SOME SEVERE REPORTS BUT MOST LIKELY
THIS WILL BE CONFINED TO THE FAR SOUTHERN PORTIONS OF THE CWA. HAVE
GONE WITH LIKELY POPS ON FRIDAY AFTERNOON INTO FRIDAY NIGHT ACRS
MUCH OF THE SOUTHERN HALF OF THE CWA WHERE BEST WAA/THETA-E
ADVECTION OCCURS. LIKELY TO SEE SOME DECENT RAINFALL WITH PWATS IN
EXCESS OF 1.50" BY FRIDAY AFTERNOON AND MAY SEE SOME LOCALIZED HEAVY
AMOUNTS. OTHERWISE...TEMPS ON FRIDAY WILL BE INFLUENCED GREATLY BY
CLOUD COVER AND HOW QUICKLY RAINFALL MOVES INTO THE AREA. GIVEN THE
UNCERTAINTY...HAVE GENERALLY STAYED CLOSE TO MOS. WL SEE MOST OF
THE FORCING PASS BY EARLY SATURDAY...HOWEVER SOME LINGERING THREAT
WL REMAIN ON SATURDAY AS A SECONDARY SHORTWAVE PASSES OVER THE
STATE. THEREAFTER...WL SEE SFC RIDGING BUILD INTO THE REGION WITH
RELATIVELY COOL TEMPERATURES AND DRY CONDITIONS. UPPER RIDGING
BEGINS TO BUILD INTO THE MIDWEST NEXT WEEK AND ANTICIPATE A GRADUAL
WARMING TREND DURING THIS TIME. WITH JET AXIS SHIFTING TO THE NORTH
ALONG WITH THE STORM TRACK...LOOKS LIKE A DRY PERIOD AS WELL.
&&
.AVIATION...03/00Z
VFR CONDITIONS ARE FORECAST DURING THE ENTIRE TAF PERIOD AS SURFACE
HIGH PRESSURE BUILDS INTO THE STATE TONIGHT THROUGH FRIDAY MORNING.
SURFACE LOW AND SHORTWAVE TROUGH ENTER REGION DURING THE DAY ON
FRIDAY. HAVE CLOUDS INCREASING BETWEEN 12-15Z FRIDAY...THEN MENTION
VICINITY SHOWERS BY THE LATE AFTERNOON FOR DSM...OTM...AND FOD.
CONFIDENCE WAS LOW ATTM TO MENTION ANY PRECIP FOR MCW AND ALO AS
SURFACE LOW TRACKS ACROSS MISSOURI LEAVING THE BEST CHANCE OF PRECIP
ACROSS THE SOUTH AND WEST.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...LEE
AVIATION...PODRAZIK
LONG TERM...COGIL
000
FXUS63 KDMX 022019
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
320 PM CDT THU JUL 2 2009
.SHORT TERM...
HIGH PRESSURE SETTLING ACROSS THE AREA WILL MAKE FOR A QUIET NIGHT.
CLOUDS THAT HAVE FORMED OVER THE EASTERN HALF OF THE STATE THIS
AFTERNOON WILL DISSIPATE AND MOVE AWAY AFTER SUNSET AND WINDS WILL
BECOME VERY LIGHT AND VARIABLE. SOME HIGH CLOUDS WILL MOVE INTO
WESTERN AND SOUTHWESTERN IOWA DURING THE EARLY MORNING
HOURS...OTHERWISE MOSTLY CLEAR SKIES WILL PREVAIL. THIS WILL LEAD TO
GOOD RADIATIONAL COOLING CONDITIONS ESPECIALLY IN OUR EASTERN AND
NORTHEASTERN COUNTIES. HAVE LOWERED MIN TEMPS TONIGHT ACROSS OUR
AREA...ESPECIALLY IN THE EAST AND NORTHEAST. HAVE ALSO REMOVED POPS
FOR LATE TONIGHT AS IT APPEARS PRECIP WILL NOT ENTER OUR AREA UNTIL
AFTER 12Z FRIDAY.
.LONG TERM...
SENSIBLE WEATHER PICKS UP ON FRIDAY INTO SATURDAY AS SHORTWAVE
SLIDES OVER RIDGE AXIS TO THE WEST. WL SEE INCREASING WAA THROUGH
THE DAY AS WINDS BECOME SOUTHEASTERLY AND THETA-E INCREASES. MODELS
DO HAVE SOME DIFFERENCE WITH NAM MUCH FARTHER NORTH THAN THE GFS OR
SREF. THE GEM AND ECMWF ARE SLOWER THAN ALL THE OTHER MODELS SO
THESE LEADS TO QUITE A BIT OF UNCERTAINTY REGARDING THE EVOLUTION OF
THIS SYSTEM. NEWEST 18Z NAM HAS COME IN A BIT FARTHER SOUTH AND
SLOWER THAN ITS 12Z COUNTERPART AND SO GIVES MORE CONFIDENCE TO THE
GFS/SREF SCENARIO. IN ALMOST ALL CASES...CAPE REMAINS IN CHECK WITH
VALUES GENERALLY UNDER 1000 J/KG. SHEAR IS QUITE GOOD...BUT MOST IF
NOT ALL INSTABILITY IS ELEVATED SO ANY REALIZATION OF THE SHEAR WILL
BE MINIMIZED. MAY STILL EEK OUT SOME SEVERE REPORTS BUT MOST LIKELY
THIS WILL BE CONFINED TO THE FAR SOUTHERN PORTIONS OF THE CWA. HAVE
GONE WITH LIKELY POPS ON FRIDAY AFTERNOON INTO FRIDAY NIGHT ACRS
MUCH OF THE SOUTHERN HALF OF THE CWA WHERE BEST WAA/THETA-E
ADVECTION OCCURS. LIKELY TO SEE SOME DECENT RAINFALL WITH PWATS IN
EXCESS OF 1.50" BY FRIDAY AFTERNOON AND MAY SEE SOME LOCALIZED HEAVY
AMOUNTS. OTHERWISE...TEMPS ON FRIDAY WILL BE INFLUENCED GREATLY BY
CLOUD COVER AND HOW QUICKLY RAINFALL MOVES INTO THE AREA. GIVEN THE
UNCERTAINTY...HAVE GENERALLY STAYED CLOSE TO MOS. WL SEE MOST OF
THE FORCING PASS BY EARLY SATURDAY...HOWEVER SOME LINGERING THREAT
WL REMAIN ON SATURDAY AS A SECONDARY SHORTWAVE PASSES OVER THE
STATE. THEREAFTER...WL SEE SFC RIDGING BUILD INTO THE REGION WITH
RELATIVELY COOL TEMPERATURES AND DRY CONDITIONS. UPPER RIDGING
BEGINS TO BUILD INTO THE MIDWEST NEXT WEEK AND ANTICIPATE A GRADUAL
WARMING TREND DURING THIS TIME. WITH JET AXIS SHIFTING TO THE NORTH
ALONG WITH THE STORM TRACK...LOOKS LIKE A DRY PERIOD AS WELL.
&&
.AVIATION...02/18Z
CLOUDS DEVELOPING ACROSS CENTRAL IOWA ATTM WILL PRODUCE CIGS FOR
MUCH OF THIS AFTERNOON BUT EXPECTED TO REMAIN VFR WITH BASES AT
FL031-045. THESE CLOUDS WILL DISSIPATE AROUND/AFTER SUNSET WITH
LIGHT AND VARIABLE WINDS AND JUST SOME HIGH CLOUDS AROUND FL150-250
OVERNIGHT. VFR CONDITIONS TO CONTINUE THROUGH THE MORNING BEFORE
SCATTERED SHRA/TSRA BECOME POSSIBLE FROM FRIDAY AFTERNOON
ONWARD...BUT BEYOND PERIOD OF 18Z TAF.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/AVIATION...LEE
LONG TERM...COGIL
000
FXUS63 KDVN 022001
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
300 PM CDT THU JUL 2 2009
.SYNOPSIS...
12Z UA SHOWS THAT THE ANOMALOUSLY DEEP...FOR THIS TIME OF YEAR...
UPPER LOW ACROSS THE GREAT LAKES HAS MOVED VERY LITTLE SINCE
YESTERDAY. CYCLONIC FLOW AND THE ASSOCIATED COLD POOL CONTINUE TO
KEEP PLENTY OF COLD WX SC ACROSS THE AREA. THE UPPER LOW HAS FILLED
CONSIDERABLY SINCE YESTERDAY. VORT MAXES ARE CONTINUING TO ROTATE
AROUND THE UPPER LOW BUT NO DZ/SPRINKLES WERE BEING INDICATED ON
RADARS OR SURFACE REPORTS. 18Z SFC ANALYSIS HAS NUMEROUS WEAK TROFS
IN THE CYCLONIC FLOW ALOFT FROM THE TENNESSEE VALLEY TO THE
INTERNATIONAL BORDER. HIGH PRESSURE RUNS FROM THE DAKOTAS INTO THE
CENTRAL PLAINS. ENERGY COMING OVER THE UPPER RIDGE HAS INITIATED
CYCLOGENESIS IN SOUTHEAST COLORADO.
&&
.SHORT TERM...TONIGHT AND FRIDAY...
SATELLITE SHOWS THE CLOUDS MORE CELLULAR THAN THE PAST TWO DAYS
INDICATING MOST WILL DISSIPATE WITH SUNSET. SFC RIDGE THEN BUILDS IN
LATE TONIGHT KEEPING QUIET WX ACROSS THE AREA. TEMPERATURES SHOULD
DROP TONIGHT DUE TO LIGHT WINDS AND NEARLY CLEAR SKIES.
QUIET WX WILL CONTINUE FRIDAY MORNING AS THE SFC RIDGE MOVES EAST OF
THE AREA. FRIDAY AFTERNOON IS LOOKING MORE INTERESTING. ENERGY
TOPPING THE WESTERN UPPER RIDGE IS STRONGER THAN DEPICTED IN THE
MODELS. SAID ENERGY WILL CREATE AN MCS IN THE NORTHERN PLAINS THAT
WILL BE IN THE DECAYING STAGE AS IT MOVES ACROSS IOWA ON FRIDAY. THE
COMBINATION OF THIS MCS AND THE LLJ SHIFTING EASTWARD IN THE
AFTERNOON SHOULD RESULT IN NEW CONVECTION FIRING BY MID TO LATE
AFTERNOON OVER OR IMMEDIATELY WEST THE CWFA. THEREFORE PLAN TO
INTRODUCE POPS IN THE LATE AFTERNOON WITH THE HIGHEST IN THE
SOUTHWEST. WILL UNDERCUT GUIDANCE AS IT HAS BEEN TOO WARM ON MAX
TEMPERATURES THE PAST TWO DAYS. ..08..
.LONG TERM...FRIDAY NIGHT THROUGH NEXT THURSDAY...
...SIGNIFICANT RAINFALL EVENT FOR SOUTH 1/2 TO 2/3 SECTIONS FRIDAY
NIGHT INTO SATURDAY MAIN FORECAST CHALLENGE...
OVERALL INITIALIZATION AND VERIFICATION OF SOLUTION SUITE SLIGHTLY
ABOVE AVERAGE WITH ISSUE OF PHASING AND EJECTING WEAK PACIFIC COAST
ENERGY BETTER CLARIFIED TODAY WITH SLIGHTLY STRONGER FORCING EVIDENT.
KINEMATIC FIELDS AND MOISTURE VERIFICATION AND RUN TO RUN CONTINUITY
SUPPORT A BLEND OF UKMET/HI-RES ECMWF. DID NOT USE MUCH OF GFS AND
NAM-WRF UNTIL SUNDAY DUE TO NOTORIOUS CONVECTIVE FEEDBACK ISSUE WHICH
CONFLICTS WITH BASIC CONCEPTUAL MODELS FOR WEEKEND RAINFALL EVENT.
UNFORTUNATELY...THIS FEEDBACK PROBLEM IS NOW ROUTINE WITH AMERICAN
MODELS AND HAS BEEN FOR QUITE AWHILE. IN BASIC TERMS...THE ENERGY
RELEASE (ENTROPY) IMBALANCES IN THESE MODELS ARE IMPROPERLY
INTERACTING WITH...AND POLLUTING KINEMATIC FIELDS. THIS RESULTS IN
A RAPID CASCADE OF ERRORS RENDERING ANY DATA VERY QUESTIONABLE W/R/T
CLOUDS AND RAINFALL.
FRIDAY NIGHT THROUGH SATURDAY...UPPED POPS MOST LOCATIONS ANOTHER 10+
PERCENT. WENT CATEGORICAL ALONG AND SOUTH OF HIGHWAY 34 WITH 925-850
MB WARM FRONT UPGLIDE OF 25-35 MPH LOW LEVEL JET TO ALLOW MODERATE TO
HEAVY RAINFALL AMOUNTS BY MID-EVENING DUE PW/S AOA 1.75". WENT LIKELY
POPS ALONG AND NEAR I-80 WITH SCATTERED EMBEDDED STORMS BUT LOCAL
STRATIFICATION PROCEDURES APPLIED TO OUR RECORD COLD AIR MASS IN-
PLACE SUGGESTS RAPID STRATIFICATION NORTH OF BOUNDARY WITH LITTLE TO
NO LIGHTNING NORTH OF I-80 UNLESS OF 925-850 MB FRONT IS PUSHED
FURTHER NORTH WHICH IS UNLIKELY ATTM. MOIST VERTICAL PROFILES AND
LIMITED INSTABILITY SUGGEST NIL SEVERE RISK...BUT A FEW STRONGER
STORMS POSSIBLE ALONG AND SOUTH OF HIGHWAY 34 FROM GUSTY WINDS TO 40
MPH IN MODEST BOWING SEGMENTS AND SOME SMALL HAIL NEAR IA/MO BORDER
FRIDAY NIGHT NEAR SFC FRONT. LOWS...MILD IN LOW/MID 60S AND POSSIBLE
STILL MAY NEED RAISING A DEGREE OR TWO IN A FEW PLACES. SATURDAY...
MORNING RAIN TO GRADUALLY END WITH MOST PRECIPITATION TO LINGER AND
CONSOLIDATE ALONG DISSIPATING 700 MB AS IS NORMAL. KEPT A FEW STORMS
POSSIBLE IN AM BUT OVERALL SUBSIDENCE TO TAKE OVER WITH NORTH WINDS
TO SUGGEST LITTLE OR CONVECTION ATTM. HIGHS A CHALLENGE...IF CLOUDS
AND PRECIPITATION HANG IN AS LONG AS SOME TECHNIQUES SUGGESTS...LATER
SHIFTS MAY NEED TO REDUCE MAXES FURTHER BY 2 TO 5 DEGREES IN SOME
LOCATIONS. OVERALL EVENT RAINFALL AMOUNTS OF .5 TO 1.5 INCHES SOUTH
OF I-80 DECREASING TO LESS THAN A QUARTER INCH ALONG HIGHWAY 20
CORRIDOR. FLASH FLOOD GUIDANCE 2+ INCHES SUGGEST LIMITED WATER
ISSUES ATTM.
SATURDAY NIGHT...SOME LINGER EVENING SHOWERS STILL POSSIBLE FAR
SOUTH WITH WEAK HIGH PRESSURE AND CLEARING SKIES SETTING UP A
FAVORABLE ENVIRONMENT FOR FOG FOR LATER SHIFTS TO CONSIDER ADDING
IN NEXT DAY OR SO IF TRENDS AND SIGNALS CONTINUE. MINS WENT OF LOW
SIDE WITH VERY FAVORABLE RADIATIONAL COOLING.
SUNDAY THROUGH THURSDAY...NW FLOW AND WEAK SURFACE HIGH PRESSURE
SUGGEST MAINLY DRY WITH SEASONABLY MODERATE HUMIDITIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES THROUGH TUESDAY. SLOW WARMING TREND
WEDNESDAY AND KEPT DRY WITH ABOVE NORMAL TEMPS BY THURSDAY. HIGHS IN
78 TO 85 DEGREE RANGE WITH MINS UPPER 50S TO LOWER 60S THOUGH
TUESDAY. THEN MID TO UPPER 80S AND LOWS MIDDLE 60S BY THURSDAY
WITH INCREASING HUMIDITY.
FRIDAY THROUGH SUNDAY...ABOVE NORMAL TEMPERATURES AND HUMID TO VERY
HUMID CONDITIONS WITH HIGHS 90 TO 95+F SUGGESTED. HEAT INDEX VALUES
WILL APPROACH OR TOP 100F FOR WARMEST WEATHER SO FAR THIS SUMMER...
MAINLY DRY. ..NICHOLS..
&&
.AVIATION...
CIGS OF 2-3KFT SHOULD SLOWLY LIFT ABOVE 3KFT THROUGH 03/00Z AS THE
UPPER LOW IS KICKED OUT OF THE GRT LKS. CELLULAR NATURE OF CLOUDS ON
SATELLITE INDICATE DISSIPATION WITH SUNSET AND NEARLY CLR SKIES.
SHOULD SEE 3-5SM VSBYS DEVELOP AFT 03/08Z AS THE SFC RIDGE MOVES
THROUGH. GROUND FOG WILL LIKELY CREATE A SCT LAYER BLO 1KFT. NOT
INCLUDED IN TAFS BUT POTENTIAL THERE FOR CIGS BLO 1KFT AND VSBYS BLO
1SM. VSBYS/CIGS SHOULD BE VFR AFT 03/13Z. CHCS FOR VCTS INCREASE AFT
03/18Z FOR KCID/KBRL. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE
IL...NONE
MO...NONE
&&
$$
08/NICHOLS
000
FXUS63 KDMX 021723 AAB
AFDDMX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
1223 PM CDT THU JUL 2 2009
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...
AN MCS OVER THE CENTRAL PLAINS IS DIVING SOUTHEAST INTO KANSAS AND
LATER THIS MORNING INTO WEST CENTRAL MISSOURI. THE CLOUD COVER FROM
THIS FEATURE IS PUSHING INTO SOUTHWEST IA AND WILL LIKELY SPREAD A
LITTLE WAYS INTO THE CWA BUT SHOULD PUSH ACROSS THE CWA BY MID TO
LATE MORNING. THE GREAT LAKES LOW IS FINALLY SHIFTING EAST THOUGH
LOW CLOUDS ARE STILL ON THE DOORSTEPS OF KALO AND KOTM. I THINK THE
LOW CLOUDS WILL MOVE OUT BY LATE MORNING OR EARLY AFTERNOON...IN
ENOUGH TIME FOR THE SUN TO HAVE SUFFICIENT TIME TO HEAT THINGS UP.
IN GENERAL I BUMPED TEMPS UP A COUPLE DEGREES IN THE SW FROM
YESTERDAY BUT REALLY WARMED TEMPS IN THE E/NE TODAY. THE UPPER
LEVEL RIDGE BUILDS INTO THE CWA MORE AS THE GREAT LAKES LOW PULLS
EAST. THE RIDGE AXIS LEANS INTO THE CWA LATER THIS AFTERNOON THUS
AT LEAST SLIGHTLY WARMER TEMPS ARE WARRANTED DESPITE THE
NORTHWESTERLY LOW LEVEL FLOW. MOISTURE INCREASES SOMEWHAT TODAY TOO
AS 60 DEGREE DEWPOINTS INCH THEIR WAY INTO THE CWA. IT WILL FEEL A
BIT MORE MUGGY TODAY THAN IN THE PAST FEW DAYS AND WE GRADUALLY
BECOME A LITTLE MORE UNSTABLE GOING INTO THE TONIGHT PERIOD.
.LONG TERM...
MDLS ARE COMING MORE IN TO AGMT WITH THE UNFOLDING OF THE NXT
SYSTEM. A GOOD OVR RUNNING SETUP WILL BE IN PLACE FOR FRI INTO FRI
NGT. CAPE IS QUITE LMTD...HWVR THE OVERALL DYNAMICS WITH 30 TO 40
KTS LLJ PRODUCING AROUND 25 KTS OF CONVERGENCE SHUD SET THE STAGE
WELL. NAM HAS THE BEST HNDL ON MASS FIELDS THRU 36 TO 48 HRS AT
LEAST AND PRODUCES 2+ INCHES OF PWAT INVOF THE BNDRY. ALTHOUGH SVR
POT IS LMTD WITH THIS SYS THERE IS SOME POTENTIAL FOR WNDS CLOSE TO
THE BNDRY WITH ENVIRON WNDS AND CORFIDI LINED UP AND QUITE STRONG
AND DECENT BULK SHEAR IS PRESENT. WUD XPCT TO SEE A DECENT FORWARD
PROPAGATING MCS...THE QUES IS WHETHER OR NOT WE CAN GET THE MXG IN
THE COOL LOW LVL AIR. MUCH OF THE ACTION WILL SHFT TO THE S OF THE
CWA BY SAT MRNG AND KEPT THE LOW POP SCENARIO IN PLACE HEADING INTO
THE REST OF THE WKND INTO NXT WK. LTL CNNG TO GOING TEMP FCST WITH
BIGEST POT FOR A BUST BEING FRI. IT WILL ALL DEPEND ON WHEN THE
PCPN BEGINS. FOR NOW BACKED OFF A LTL WITH TEMPS IN THE MID TO
UPPER 70S. IF THE PCPN BEGINS MUCH BFR 18Z IT WILL BE DIF TO GET
MUCH ABV 70. SLOW MODERATION BY SUN INTO NXT WK. WITH BLOCK OFF TO
THE EAST AND ELY FLOW OVR THE CWA DON`T LOOK FOR THINGS TO WRM ALL
THAT FAST.
&&
.AVIATION...02/18Z
CLOUDS DEVELOPING ACROSS CENTRAL IOWA ATTM WILL PRODUCE CIGS FOR
MUCH OF THIS AFTERNOON BUT EXPECTED TO REMAIN VFR WITH BASES AT
FL031-045. THESE CLOUDS WILL DISSIPATE AROUND/AFTER SUNSET WITH
LIGHT AND VARIABLE WINDS AND JUST SOME HIGH CLOUDS AROUND FL150-250
OVERNIGHT. VFR CONDITIONS TO CONTINUE THROUGH THE MORNING BEFORE
SCATTERED SHRA/TSRA BECOME POSSIBLE FROM FRIDAY AFTERNOON
ONWARD...BUT BEYOND PERIOD OF 18Z TAF.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...MS JUL 09
AVIATION...LEE
000
FXUS63 KDMX 021150 AAA
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
644 AM CDT THU JUL 2 2009
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...
AN MCS OVER THE CENTRAL PLAINS IS DIVING SOUTHEAST INTO KANSAS AND
LATER THIS MORNING INTO WEST CENTRAL MISSOURI. THE CLOUD COVER FROM
THIS FEATURE IS PUSHING INTO SOUTHWEST IA AND WILL LIKELY SPREAD A
LITTLE WAYS INTO THE CWA BUT SHOULD PUSH ACROSS THE CWA BY MID TO
LATE MORNING. THE GREAT LAKES LOW IS FINALLY SHIFTING EAST THOUGH
LOW CLOUDS ARE STILL ON THE DOORSTEPS OF KALO AND KOTM. I THINK THE
LOW CLOUDS WILL MOVE OUT BY LATE MORNING OR EARLY AFTERNOON...IN
ENOUGH TIME FOR THE SUN TO HAVE SUFFICIENT TIME TO HEAT THINGS UP.
IN GENERAL I BUMPED TEMPS UP A COUPLE DEGREES IN THE SW FROM
YESTERDAY BUT REALLY WARMED TEMPS IN THE E/NE TODAY. THE UPPER
LEVEL RIDGE BUILDS INTO THE CWA MORE AS THE GREAT LAKES LOW PULLS
EAST. THE RIDGE AXIS LEANS INTO THE CWA LATER THIS AFTERNOON THUS
AT LEAST SLIGHTLY WARMER TEMPS ARE WARRANTED DESPITE THE
NORTHWESTERLY LOW LEVEL FLOW. MOISTURE INCREASES SOMEWHAT TODAY TOO
AS 60 DEGREE DEWPOINTS INCH THEIR WAY INTO THE CWA. IT WILL FEEL A
BIT MORE MUGGY TODAY THAN IN THE PAST FEW DAYS AND WE GRADUALLY
BECOME A LITTLE MORE UNSTABLE GOING INTO THE TONIGHT PERIOD.
.LONG TERM...
MDLS ARE COMING MORE IN TO AGMT WITH THE UNFOLDING OF THE NXT
SYSTEM. A GOOD OVR RUNNING SETUP WILL BE IN PLACE FOR FRI INTO FRI
NGT. CAPE IS QUITE LMTD...HWVR THE OVERALL DYNAMICS WITH 30 TO 40
KTS LLJ PRODUCING AROUND 25 KTS OF CONVERGENCE SHUD SET THE STAGE
WELL. NAM HAS THE BEST HNDL ON MASS FIELDS THRU 36 TO 48 HRS AT
LEAST AND PRODUCES 2+ INCHES OF PWAT INVOF THE BNDRY. ALTHOUGH SVR
POT IS LMTD WITH THIS SYS THERE IS SOME POTENTIAL FOR WNDS CLOSE TO
THE BNDRY WITH ENVIRON WNDS AND CORFIDI LINED UP AND QUITE STRONG
AND DECENT BULK SHEAR IS PRESENT. WUD XPCT TO SEE A DECENT FORWARD
PROPAGATING MCS...THE QUES IS WHETHER OR NOT WE CAN GET THE MXG IN
THE COOL LOW LVL AIR. MUCH OF THE ACTION WILL SHFT TO THE S OF THE
CWA BY SAT MRNG AND KEPT THE LOW POP SCENARIO IN PLACE HEADING INTO
THE REST OF THE WKND INTO NXT WK. LTL CNNG TO GOING TEMP FCST WITH
BIGEST POT FOR A BUST BEING FRI. IT WILL ALL DEPEND ON WHEN THE
PCPN BEGINS. FOR NOW BACKED OFF A LTL WITH TEMPS IN THE MID TO
UPPER 70S. IF THE PCPN BEGINS MUCH BFR 18Z IT WILL BE DIF TO GET
MUCH ABV 70. SLOW MODERATION BY SUN INTO NXT WK. WITH BLOCK OFF TO
THE EAST AND ELY FLOW OVR THE CWA DON`T LOOK FOR THINGS TO WRM ALL
THAT FAST.
&&
.AVIATION...02/12Z
BENIGN WEATHER THROUGH 03/00Z. LOW CLOUDS FROM THE GREAT LAKES LOW
ARE FINALLY PUSHING EAST OF THE CWA WHILE ONLY HIGH LEVEL CLOUDS
FROM AN MCS TO OUR WEST MOVING INTO SW IA. AFT 03/00Z THE SFC HIGH
PUSHES TO THE SOUTHEAST ALLOWING A LOW PRESSURE SYSTEM OVER THE
PLAINS TO PUSH EAST. FLOW WILL TURN SOUTHERLY AND WARM AIR
ADVECTION LATER TONIGHT WILL BRING IN MID LEVEL CLOUD COVER. THE
WEATHER WILL DETERIORATE AFTER THE FORECAST PERIOD AS THUNDERSTORM
CHANCES INCREASE AFT 03/12Z.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/AVIATION...FAB
LONG TERM...MS JUL 09
000
FXUS63 KDMX 020836
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
325 AM CDT THU JUL 2 2009
.SHORT TERM...
A MCS OVER THE CENTRAL PLAINS IS DIVING SOUTHEAST INTO KANSAS AND
LATER THIS MORNING INTO WEST CENTRAL MISSOURI. THE CLOUD COVER FROM
THIS FEATURE IS PUSHING INTO SOUTHWEST IA AND WILL LIKELY SPREAD A
LITTLE WAYS INTO THE CWA BUT SHOULD PUSH ACROSS THE CWA BY MID TO
LATE MORNING. THE GREAT LAKES LOW IS FINALLY SHIFTING EAST THOUGH
LOW CLOUDS ARE STILL ON THE DOORSTEPS OF KALO AND KOTM. I THINK THE
LOW CLOUDS WILL MOVE OUT BY LATE MORNING OR EARLY AFTERNOON...IN
ENOUGH TIME FOR THE SUN TO HAVE SUFFICIENT TIME TO HEAT THINGS UP.
IN GENERAL I BUMPED TEMPS UP A COUPLE DEGREES IN THE SW FROM
YESTERDAY BUT REALLY WARMED TEMPS IN THE E/NE TODAY. THE UPPER
LEVEL RIDGE BUILDS INTO THE CWA MORE AS THE GREAT LAKES LOW PULLS
EAST. THE RIDGE AXIS LEANS INTO THE CWA LATER THIS AFTERNOON THUS
AT LEAST SLIGHTLY WARMER TEMPS ARE WARRANTED DESPITE THE
NORTHWESTERLY LOW LEVEL FLOW. MOISTURE INCREASES SOMEWHAT TODAY TOO
AS 60 DEGREE DEWPOINTS INCH THEIR WAY INTO THE CWA. IT WILL FEEL A
BIT MORE MUGGY TODAY THAN IN THE PAST FEW DAYS AND WE GRADUALLY
BECOME A LITTLE MORE UNSTABLE GOING INTO THE TONIGHT PERIOD.
.LONG TERM...
MDLS ARE COMING MORE IN TO AGMT WITH THE UNFOLDING OF THE NXT
SYSTEM. A GOOD OVR RUNNING SETUP WILL BE IN PLACE FOR FRI INTO FRI
NGT. CAPE IS QUITE LMTD...HWVR THE OVERALL DYNAMICS WITH 30 TO 40
KTS LLJ PRODUCING AROUND 25 KTS OF CONVERGENCE SHUD SET THE STAGE
WELL. NAM HAS THE BEST HNDL ON MASS FIELDS THRU 36 TO 48 HRS AT
LEAST AND PRODUCES 2+ INCHES OF PWAT INVOF THE BNDRY. ALTHOUGH SVR
POT IS LMTD WITH THIS SYS THERE IS SOME POTENTIAL FOR WNDS CLOSE TO
THE BNDRY WITH ENVIRON WNDS AND CORFIDI LINED UP AND QUITE STRONG
AND DECENT BULK SHEAR IS PRESENT. WUD XPCT TO SEE A DECENT FORWARD
PROPAGATING MCS...THE QUES IS WHETHER OR NOT WE CAN GET THE MXG IN
THE COOL LOW LVL AIR. MUCH OF THE ACTION WILL SHFT TO THE S OF THE
CWA BY SAT MRNG AND KEPT THE LOW POP SCENARIO IN PLACE HEADING INTO
THE REST OF THE WKND INTO NXT WK. LTL CNNG TO GOING TEMP FCST WITH
BIGEST POT FOR A BUST BEING FRI. IT WILL ALL DEPEND ON WHEN THE
PCPN BEGINS. FOR NOW BACKED OFF A LTL WITH TEMPS IN THE MID TO
UPPER 70S. IF THE PCPN BEGINS MUCH BFR 18Z IT WILL BE DIF TO GET
MUCH ABV 70. SLOW MODERATION BY SUN INTO NXT WK. WITH BLOCK OFF TO
THE EAST AND ELY FLOW OVR THE CWA DON`T LOOK FOR THINGS TO WRM ALL
THAT FAST.
&&
.AVIATION...02/06Z
STILL LOOKING AT A QUIET PERIOD FOR THIS TAF PACKAGE BEFORE WX
BECOMES MORE ACTIVE AFT 18Z/03 FOR PORTIONS OF THE FORECAST AREA.
MEANWHILE WITH RIDGE OF HIGH PRESSURE STILL DRIFTING OVER THE AREA
TNT AND EARLY THURS...EXPECT TO SEE SOME BR/HZ FORM OVER THE REGION.
AT PRESENT...FAVORED AREAS FOR EARLY MORNING VSBY RESTRICTIONS
APPEAR TO BE KALO...KMCW...AND KOTM. HAVE RAISED KDSM VISBY TO 6SM
HZ BASED ON CURRENT TEMP AND TD SPREAD. NEARING SATURATION OVER THE
NORTH ATTM...SO AM EXPECTING BETTER POTENTIAL THERE BETWEEN 08-11Z.
OTHERWISE...FAIR WX CU AND SOME LIGHT MIXING WILL OCCUR ON THURSDAY.
SOUNDINGS SUPPORT 13-15KT GUSTS DURING LATE MORNING AND AFTERNOON
HOURS MOST SECTIONS WITH RAPID DECOUPLING AFT 23Z. AS AREA OF WARM
AIR ADVECTION BEGINS TO ARRIVE AFT 03/00Z...WILL EXPECT GRADUAL
INCREASE IN MID LEVEL CLOUDS AND HAVE ADDED SCT-BKN100-150 FOR WEST.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...FAB
AVIATION...REV
LONG TERM...MS JUL 09
000
FXUS63 KDVN 020823
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
323 AM CDT THU JUL 2 2009
.SYNOPSIS...
LARGE CUT-OFF UPPER LOW... RESPONSIBLE FOR THE UNSEASONABLY COOL
AIRMASS OVER PAST FEW DAYS WITH HIGH TEMPS 15-20 DEGS BELOW
NORMAL... CONTINUES TO MEANDER ABOUT THE GREAT LAKES EARLY THIS
MORNING. SATELLITE AND 00Z SUBJECTIVE UPPER AIR ANALYSIS SHOW
SIGNS OF SYSTEM WEAKENING AND BEGINNING TO LIFT N/E... AS
WESTERN CANADA LOW /UPSTREAM KICKER/ INCHES EASTWARD AND CLOSE
ENOUGH IN PROXIMITY TO GIVE SYSTEM NUDGE AS OPPOSED TO THE BOOT.
THUS... PROCESS WILL BE GRADUAL BUT NONETHELESS SIGNALS
IMPROVEMENT IN THE TEMP DEPT NEXT FEW DAYS WITH A RETURN TO
NEAR NORMAL. LOW/MID LEVEL BAROCLINIC ZONE EXTENDING N/W TO S/E
THROUGH THE PLAINS REMAINS THE FOCAL POINT FOR CONVECTION
WITH LARGE DECAYING COMPLEX TRAVERSING PORTIONS OF NE AND KS.
11-3.9 MICRON SATELLITE SHOWS MAIN LOW CLOUD DECK ARCING THROUGH
MIDSECTION OF CWA WITH MAIN BAND 80-100 MI WIDE. EROSION HAS
TAKEN PLACE ON THE EDGES... S/W AND MORE PRONOUNCED N/E LIKELY
ATTRIBUTED TO SUBSIDENCE IN WAKE OF IMPULSE DIVING DOWN ACROSS
LAKE MI. N/E EROSION HAD BEEN MOVING S/W AT 10-13 KTS... BUT
RECENT TRENDS SHOW THIS HAS SLOWED CONSIDERABLY. TEMPS VARYING
QUITE A BIT EARLY THIS MORNING. WHERE SKIES HAVE CLEARED TEMPS
HAVE LOWERED IN RANGE OF 52-54 DEGS WITH LIGHT WINDS. MEANWHILE...
BENEATH MAIN CLOUD BAND TEMPS BEING HELD UP AROUND 60 OR L60S.
..MCCLURE..
&&
.SHORT TERM...TODAY AND TONIGHT...
MAIN FCST CHALLENGE IS CLOUD TRENDS WITH IMPACT ON TEMPS.
GREAT LAKES LOW TO FINALLY LOOSEN IT/S GRIP ON REGIONAL WX AS IT
WEAKENS WHILE GRADUALLY DRIFTING TOWARD SOUTHERN QUEBEC NEXT
24 HRS. THIS WILL IN TURN ALLOW TEMPERATURES TO MODERATE... BUT
STILL REMAIN BELOW NORMAL TODAY. AS FOR CLOUDS... MAIN BAND
EXTENDING THROUGH HEART OF CWA EARLY THIS MORNING LIKELY TO DRIFT
SOME AND BLANKET MUCH OF THE S/W 1/3-1/2 BY DAYBREAK... WHILE
SOME CLEARING WILL BE FOUND ON THE EDGES. HOWEVER... AMPLE LOW
LEVEL MOISTURE...CYCLONIC FLOW AND HEATING SHOULD FUEL CU
DEVELOPMENT WITH MODELS CU RULE SUPPORTING BKN-OVC SKIES MUCH OF
CWA BY MID-LATE MORNING INTO EARLY AFTN. THIS AFTN... COMBINATION
OF MIXING INTO DRY MID LEVELS AND SOME WEAK WARM ADVECTION ALOFT
SHOULD BE SUFFICIENT TO SCT OUT CLOUDS WEST AND CONTINUING
INTO EVE EAST WITH BL COOLING. AS FOR TEMPS... CURRENT FCST OF
COOLER READINGS EAST AND WARMER WEST LOOKS RIGHT ON TARGET. THUS
SIDED AT OR A LITTLE BELOW COOLEST MOS GUIDANCE EAST (L-M 70S)
AND BLEND TO NEAR WARM SIDE OF GUIDANCE WEST (U70S/L80S). SKIES
CLEARING OR MAINLY CLEAR TONIGHT WITH JUST SOME PATCHY MID AND HIGH
CLOUDINESS S/W SECTIONS WITH WARM ADVECTION AND BLOW OFF FROM
CONVECTION IN PLAINS. ANTICIPATE IDEAL RADIATIONAL COOLING SETUP
MUCH OF AREA EXCEPT FAR S/W TO SUPPORT SIDING AT OR JUST BELOW COOL
SIDE OF GUIDANCE ON MINS. NAM/GFS BUFR SOUNDINGS SHOW SHARP LOW
LEVEL INVERSION DEVELOPING OVRNGT WHICH WOULD BE CONDUCIVE FOR SOME
GROUND FOG AND QUITE VARIABLE ON VSBYS. BELIEVE PATCHY ENOUGH WITH
LITTLE CHC OF SIGNIFICANT IMPACT TO WARRANT MENTION IN ZFP/GRIDS AND
MORE CONCERN FOR AVIATION. ..MCCLURE..
.LONG TERM...FRIDAY THROUGH WEDNESDAY...
MODELS CONTINUE TO TREND TOWARD A MORE NORTHERLY POSITION OF
CRITICAL H8 AND SURFACE BOUNDARIES...INCREASING THE CONFIDENCE THAT
THE SOUTHERN HALF OF THE FORECAST AREA WILL HAVE RAIN FRI NIGHT AND
AT LEAST EARLY ON THE 4TH OF JULY HOLIDAY. ECMWF HAS MADE THE
LARGEST SHIFTS NORTHWARD THE PAST COUPLE RUNS. THE 00Z HAS BOTH A
SLOWER AND MORE NRLY H8 CIRCULATION...TRACKING FROM EASTERN NEB SE
ALONG THE IA/MO BORDER DURING THE DAY. THE INVERTED SURFACE TROUGH
AND ELEVATED CONVERGENCE WOULD SUPPORT THE WIDESPREAD RAIN SHOWN BY
ITS QPF FIELDS OVER THE ENTIRE AREA LATE FRI NIGHT THROUGH SAT. THIS
SOLUTION HAS GOOD SUPPORT BY THE LATEST UKMET WITH A BLEND
SUGGESTING HEAVIEST RAIN BETWEEN HIGHWAY 34 AND I-80 CORRIDOR.
HOWEVER...WITH SUCH A LARGE CHANGE FROM THE PREVIOUS FORECASTS FOR
THIS CRITICAL TIME PERIOD...HAVE KEPT FORECAST TRENDED CLOSER TO A
FASTER A SLIGHTLY MORE SOUTHERLY AND MORE CONSISTENT WRF/NAM
SOLUTION.
ON FRI...DRY LOW AND MID LEVELS UNDER LINGERING WEAK SURFACE RIDGE
INITIALLY FROM MN INTO IL WILL TAKE A WHILE TO SATURATE AS UPPER
FORCING AHEAD OF THE SHORTWAVE IN THE NW FLOW ARRIVES IN THE
AFTERNOON. HAVE CONFINED LOW CHANCE POPS FOR AFTERNOON THUNDERSTORMS
TO THE W AND SW CLOSEST TO THE INCOMING ELEVATED MOISTURE AND WAA.
OVERNIGHT...RAISED POPS TO LIKELY ACROSS NE MO INTO FAR SE IA IN
AREA OF STRONGEST CONVERGENCE AHEAD OF THE WAVE THAT TRACKS ALONG
THE TIGHT H8 BOUNDARY ACROSS NRN MO INTO CENTRAL IL. WITH POOLING H8
DEWPOINTS IN 14 TO 16 DEG C RANGE...HAVE MODERATE QPF AMOUNTS IN
THIS AREA OVER .75 INCHES. DUE TO THE STRENGTH OF THE WAA FED BY
WINDS OF 40 TO 50 KTS....KEPT WIDESPREAD THUNDERSTORM WORDING ACROSS
THE SOUTH ALTHOUGH MORE FAVORABLE MID LEVEL LAPSE RATES STAY WELL TO
THE SOUTH. FURTHER NORTH...TSRA CHANCES LOOK MUCH MORE LIMITED OVERNIGHT
DUE TO MORE STABLE MID LEVEL LAPSE RATES AND HAVE ONLY ISOLATED
WORDING WITH QPF TRENDING TO LESS THAN .10 NORTH OF I-80.
ON THE 4TH HOLIDAY...BACK EDGE OF OVERNIGHT MCS WILL LIKELY BE
EXITING THE FAR SOUTH IN THE MORNING AND THIS IS WHERE BEST CHANCES
FOR RAIN CONFINED. HOWEVER...WITH LINGERING MOIST LOW LEVEL E-NE
FLOW BEHIND THE DEPARTING SURFACE WAVE AND SERIES OF WEAK WAVES
EMBEDDED IN THE NW FLOW...WILL KEEP AT LEAST SLIGHT CHANCE POPS GOING
THROUGH THE DAY ACROSS ESPECIALLY THE SOUTH. AMOUNT OF CLOUD COVER
WILL BE CRITICAL TO HOW MUCH WARMING CAN OCCUR. FOR NOW STAYED
CLOSER TO MORE OPTIMISTIC GFS/MAV NUMBERS WITH THE NORTH SLIGHTLY
WARMER THAN THE SOUTH IN A RANGE FROM AROUND 80 TO THE UPPER 70S.
ANOTHER SYSTEM SLIDES BY WELL TO THE SOUTH ON SUN...ALONG THE
SURFACE AND H8 BOUNDARY SHOWN TO GET NUDGED FURTHER SOUTH. LOCAL
AREA WILL BE UNDER THE INFLUENCE OF WEAK HIGH PRESSURE OVER THE
GREAT LAKES WHICH ALONG WITH A BUILDING UPPER RIDGE TO THE
WEST...SHOULD KEEP A DRY FORECAST WITH TEMPERATURES JUST BELOW
SEASONAL NORMS GOING INTO NEXT WEEK.
..SHEETS..
&&
.AVIATION...
LARGE GREAT LAKES LOW TO WEAKEN AND LIFT INTO SOUTHERN QUEBEC NEXT
24 HRS ALLOWING GRADUAL IMPROVEMENT IN CLOUD TRENDS. EARLY THIS
MORNING SATELLITE SHOWS EXTENSIVE BAND OF LOW CLOUDS WITH MVFR-VFR
CIGS BLANKETING TERMINALS. SOME CLEARING HAS TAKEN PLACE ON THE
EDGES WHICH MAY RESULT IN BRIEF PERIOD OF CLEARING OR SCATTERING OUT
OF LOW CLOUDS ESPECIALLY AT KDBQ AND POSSIBLY KCID AND KBRL PRIOR TO
SUNRISE. HOWEVER...AMPLE MOISTURE AND HEATING SHOULD RESULT IN
CU DEVELOPMENT BY MID-LATE MORNING IN ANY AREAS THAT CLEAR. MODEL CU
RULE SUPPORTS BKN-OVC MVFR-VFR CIGS INTO AFTN. MIXING OF DRY MID
LEVEL AIR AND SOME WARM ADVECTION SHOULD RESULT IN CLEARING TREND
FROM WEST TO EAST THIS AFTN INTO EVE. N/NW WINDS INCREASE TO 8-13 KTS
BY LATE MORNING THEN DIMINISH TO WESTERLY AOB 5 KTS TONIGHT WITH
POTENTIAL FOR PERIOD OF NEAR CALM WIND. MODEL SOUNDINGS SUGGEST
SHARP LOW LEVEL INVERSION DEVELOPING OVERNIGHT WHICH WOULD BE
CONDUCIVE FOR GROUND FOG WITH POTENTIAL FOR QUITE VARIABLE VSBYS.
WILL HANDLE WITH TEMPO GROUP OF MVFR VSBYS FOR NOW AT MOST SITES
08Z-12Z TIMEFRAME. ..MCCLURE..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
MCCLURE/SHEETS
| 
