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000
FXUS64 KJAN 051445 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE JACKSON MS
945 AM CDT SUN JUL 5 2009
.DISCUSSION...
UPDATE: STRONGER CONVECTION IS PASSING JUST NORTH OF THE FORECAST
AREA THIS MORNING...WITH ANOTHER CONVECTIVE COMPLEX MOVING SLOWLY
SOUTHEAST OUT OF THE ARKLATEX REGION TOWARD THE FORECAST AREA. NOT
MUCH HAS CHANGED WITH THINKING ON SEVERE WEATHER POTENTIAL FOR LATER
TODAY/EVNG. DIURNAL HEATING IS FURTHER DESTABILIZING A MOIST AND
UNSTABLE AIRMASS WITH PRECIP WATER VALUES EXPECTED TO APPROACH 2
INCHES AS MOISTURE POOLS ALONG AND AHEAD OF AN APPROACHING COLD
FRONT. LOCAL WRF OUTPUT SUGGESTS SCATTERED SHOWERS/TSTMS SHOULD
DEVELOP OUT AHEAD OF THE APPROACHING CONVECTIVE COMPLEX DURING THE
EARLY/MID AFTN AND GIVEN SUFFICIENT DEEP LAYER SHEAR IN PLACE...
EXPECT TSTMS TO ORGANIZE INTO LINE SEGMENTS CAPABLE OF PRODUCING
DAMAGING WIND GUSTS/HAIL PER HWO. HAVE PLACED HIGHEST POPS AND
GREATEST RISK FOR SVR WEATHER IN THE FORECAST GRIDS FROM MID AFTN
THROUGH EARLY EVNG. /EC/
PREVIOUS DISCUSSION...
SHORT TERM(TODAY THROUGH MONDAY NIGHT) ALL MODELS ARE
CONTINUING TO SHOW WIDESPREAD RAIN AND THUNDERSTORM CHANCES FOR THE
NEXT 36 HOURS...AND THE BEST CHANCES ARE FOR THE NORTHERN 2/3RDS OF
THE AREA TODAY. SPC HAS HIGHLIGHTED A SLIGHT RISK OF SEVERE WEATHER
GIVEN THAT WE WILL BE IN THE RIGHT ENTRANCE REGION OF A DECENT 250MB
JET...30KT 850MB WINDS...AND LOWER 70F DEWPOINTS NEAR A LOW LEVEL
CONVERGENCE ZONE. THIS POTENTIAL WILL BE MENTIONED IN THE HWO. AS
THE FRONT MOVES FURTHER TO THE SOUTH ON MONDAY...CONVECTION SHOULD
BE MORE FOCUSED IN CENTRAL AND SOUTHERN ZONES. HERE AGAIN SOME OF
THESE STORMS COULD BE ON THE STRONG SIDE.
WE WILL HAVE ANOTHER DAY OF ABOVE NORMAL TEMPERATURES TO DEAL WITH
FOR THE SOUTHERN HALF OF THE JAN CWA TODAY AHEAD OF AN APPROACHING
FRONTAL BOUNDARY FROM THE NORTH. THE NAM SEEMED TO HAVE AN EXCELLENT
HANDLE ON DAYTIME HIGHS...SO THOSE WERE USED IN THE FORECAST. THIS IS
ABOUT 3 DEGREES ABOVE MAV GUIDANCE FOR SOUTHERN ZONES WHERE IT WILL
BE DRIER...AND ABOUT 4 DEGREES BELOW FOR NORTHERN ZONES...OWING TO
THE INCREASED CLOUD COVER AND RAIN CHANCES THERE. THESE LOWER TEMPS
WILL CERTAINLY BE WELCOMED BY MANY AS MOST SITES IN THE CWA HAVE BEEN
RUNNING IN THE MID TO UPPER 90S FOR AT LEAST TWO STRAIGHT WEEKS
NOW...NOT TO MENTION SOME OF THE 100+ DEGREE READINGS OF LATE. IT
WILL STILL REMAIN RATHER MUGGY THROUGH THE SHORT TERM AS ALL OF THE
LOW LEVEL MOISTURE TRANSLATES TO UPPER 60S AND LOWER 70S DEWPOINTS.
BEYOND TODAY...MAV GUIDANCE WAS GENERALLY ACCEPTED FOR TEMPS. /DH/
LONGER TERM(TUESDAY THROUGH SATURDAY)...THE EARLY WEEK COLLAPSE OF
THE UPPER RIDGING AND SUBSEQUENT RETROGRADING OF THE HIGH LEVEL
ANTICYCLONE TO THE NM AREA BY THE END OF THE WEEK SHOULD GIVE US
SOME NEEDED HEAT RELIEF. SUB 590DM 500MB HEIGHTS AND A LINGERING
TROUGH AXIS FROM THE SRN APPALACHIANS TO THE LA COAST WILL ALLOW AT
LEAST DIURNAL TSRA TO CONTINUE OVER SRN PORTIONS OF THE CWFA WHERE
THE STALLED FRONTAL BOUNDARY ALONG THE COAST AND SEA BREEZE
INFLUENCES MINGLE EACH DAY. ALL OF THE ECMWF...GFS AND NAM RUNS
SUPPORT AT LEAST 1 TO 3 INCH QPF TOTALS FOR LOCATIONS FROM
INTERSTATE 20 SWD BY MIDDAY TUESDAY WHICH WOULD BE VERY MUCH
WELCOMED. THERE ARE ALSO BETTER HINTS AT A CUTOFF UPPER LOW CENTER
FORMING IN SERN LA BY THURSDAY ON THE OPERATIONAL MODEL RUNS. THIS
COULD HELP FOCUS SOME HEAVY RAINFALL AND WILL NEED TO BE MONITORED.
THE TROPICS APPEAR TO REMAIN QUIET FOR THE UPCOMING WEEK WITH ANY
POTENTIAL DEVELOPMENT CONFINED TO THE EPAC...THE ECMWF FORMS AT
LEAST TWO STORMS IN THE EPAC. IN ANY CASE...OUR BEST POPS WILL SHIFT
TO OVER THE SRN PORTIONS OF THE CWFA DURING THE ENTIRE WEEK WITH A
PUSH NWD BY FRIDAY NIGHT/SATURDAY WHEN A DECENT LOOKING 300MB TROUGH
AXIS BACKS WWD INTO THE REGION. TEMPS SHOULD RETURN CLOSER TO
NORMALS AT LOCATIONS WITH THE BEST RAIN CHANCES...MAINLY ON TUESDAY
AFTERNOON WHEN SOME MICROBURST POTENTIAL SHOULD EXIST OVER THE S.
HAVE MADE SLIGHT UPWARD ADJUSTMENTS TO MAXES/MINS AT LOCATIONS
HAVING THE LOWER POPS. MEX ENSEMBLE MEAN TEMPS REMAIN STILL SLIGHTLY
ABOVE THE OPERATIONAL RUN VALUES./40/
&&
.AVIATION...EXPECT INCREASING HIGH CLOUDINESS AT ALL TAF SITES FOR
THE REST OF THE EARLY MORNING HOURS...WITH SOME MID LEVEL CLOUDS
MOVING INTO GLH AND GWO. SOME SHOWER OR THUNDERSTORM ACTIVITY WILL
APPROACH GLH AND GWO AROUND OR SHORTLY AFTER 12Z...BUT THAT ACTIVITY
SHOULD BE WEAKENING BY THEN. THE STORMS SHOULD REDEVELOP DURING THE
AFTERNOON HOURS AND CONTINUE TO DROP SOUTHEAST WITH POSSIBLE IMPACT
AT GTR...MEI...AND JAN BEFORE 00Z MONDAY. DUE TO UNCERTAINTY AT THIS
TIME...HAVE KEPT ALL MENTION OF STORMS AT THE AFOREMENTIONED SITES IN
THE VICINITY. THUNDERSTORMS HAVE NOT BEEN MENTIONED AT HBG FOR NOW AS
POSSIBLE IMPACT THERE SHOULD BE AFTER 00Z MONDAY. /DH/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
000
FXUS64 KJAN 050850
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
350 AM CDT SUN JUL 5 2009
.DISCUSSION...SHORT TERM(TODAY THROUGH MONDAY NIGHT) ALL MODELS ARE
CONTINUING TO SHOW WIDESPREAD RAIN AND THUNDERSTORM CHANCES FOR THE
NEXT 36 HOURS...AND THE BEST CHANCES ARE FOR THE NORTHERN 2/3RDS OF
THE AREA TODAY. SPC HAS HIGHLIGHTED A SLIGHT RISK OF SEVERE WEATHER
GIVEN THAT WE WILL BE IN THE RIGHT ENTRANCE REGION OF A DECENT 250MB
JET...30KT 850MB WINDS...AND LOWER 70F DEWPOINTS NEAR A LOW LEVEL
CONVERGENCE ZONE. THIS POTENTIAL WILL BE MENTIONED IN THE HWO. AS OF
08Z THIS MORNING...A BROAD ZONE OF RAIN WITH EMBEDDED STORMS WAS
NOTED FROM EAST TO WEST ACROSS MUCH OF CENTRAL AR AND WESTERN
TN...WITH A MOVEMENT TOWARDS THE ESE. THIS WILL SET OUT AN OUTFLOW
BOUNDARY OVER NORTHERN ZONES BY 14Z...AND IT IS IN THE GENERAL
VICINITY OF THIS OUTFLOW BOUNDARY WHERE CONVECTION CAN BE EXPECTED TO
ERUPT DURING THE MIDDAY HOURS...AND A FEW OF THESE STORMS COULD
BECOME STRONG TO SEVERE WITH THE BIGGEST PROBLEM BEING DAMAGING WIND
GUSTS GIVEN THE HOT SURFACE TEMPS AND STEEP LOW-LEVEL LAPSE RATES. AS
THE FRONT MOVES FURTHER TO THE SOUTH ON MONDAY...CONVECTION SHOULD
BE MORE FOCUSED IN CENTRAL AND SOUTHERN ZONES. HERE AGAIN SOME OF
THESE STORMS COULD BE ON THE STRONG SIDE.
WE WILL HAVE ANOTHER DAY OF ABOVE NORMAL TEMPERATURES TO DEAL WITH
FOR THE SOUTHERN HALF OF THE JAN CWA TODAY AHEAD OF AN APPROACHING
FRONTAL BOUNDARY FROM THE NORTH. THE NAM SEEMED TO HAVE AN EXCELLENT
HANDLE ON DAYTIME HIGHS...SO THOSE WERE USED IN THE FORECAST. THIS IS
ABOUT 3 DEGREES ABOVE MAV GUIDANCE FOR SOUTHERN ZONES WHERE IT WILL
BE DRIER...AND ABOUT 4 DEGREES BELOW FOR NORTHERN ZONES...OWING TO
THE INCREASED CLOUD COVER AND RAIN CHANCES THERE. THESE LOWER TEMPS
WILL CERTAINLY BE WELCOMED BY MANY AS MOST SITES IN THE CWA HAVE BEEN
RUNNING IN THE MID TO UPPER 90S FOR AT LEAST TWO STRAIGHT WEEKS NOW...
NOT TO MENTION SOME OF THE 100+ DEGREE READINGS OF LATE. IT WILL
STILL REMAIN RATHER MUGGY THROUGH THE SHORT TERM AS ALL OF THE LOW
LEVEL MOISTURE TRANSLATES TO UPPER 60S AND LOWER 70S DEWPOINTS.
BEYOND TODAY...MAV GUIDANCE WAS GENERALLY ACCEPTED FOR TEMPS. /DH/
LONGER TERM(TUESDAY THROUGH SATURDAY)...THE EARLY WEEK COLLAPSE OF
THE UPPER RIDGING AND SUBSEQUENT RETROGRADING OF THE HIGH LEVEL
ANTICYCLONE TO THE NM AREA BY THE END OF THE WEEK SHOULD GIVE US
SOME NEEDED HEAT RELIEF. SUB 590DM 500MB HEIGHTS AND A LINGERING
TROUGH AXIS FROM THE SRN APPALACHIANS TO THE LA COAST WILL ALLOW AT
LEAST DIURNAL TSRA TO CONTINUE OVER SRN PORTIONS OF THE CWFA WHERE
THE STALLED FRONTAL BOUNDARY ALONG THE COAST AND SEA BREEZE
INFLUENCES MINGLE EACH DAY. ALL OF THE ECMWF...GFS AND NAM RUNS
SUPPORT AT LEAST 1 TO 3 INCH QPF TOTALS FOR LOCATIONS FROM
INTERSTATE 20 SWD BY MIDDAY TUESDAY WHICH WOULD BE VERY MUCH
WELCOMED. THERE ARE ALSO BETTER HINTS AT A CUTOFF UPPER LOW CENTER
FORMING IN SERN LA BY THURSDAY ON THE OPERATIONAL MODEL RUNS. THIS
COULD HELP FOCUS SOME HEAVY RAINFALL AND WILL NEED TO BE MONITORED.
THE TROPICS APPEAR TO REMAIN QUIET FOR THE UPCOMING WEEK WITH ANY
POTENTIAL DEVELOPMENT CONFINED TO THE EPAC...THE ECMWF FORMS AT
LEAST TWO STORMS IN THE EPAC. IN ANY CASE...OUR BEST POPS WILL SHIFT
TO OVER THE SRN PORTIONS OF THE CWFA DURING THE ENTIRE WEEK WITH A
PUSH NWD BY FRIDAY NIGHT/SATURDAY WHEN A DECENT LOOKING 300MB TROUGH
AXIS BACKS WWD INTO THE REGION. TEMPS SHOULD RETURN CLOSER TO
NORMALS AT LOCATIONS WITH THE BEST RAIN CHANCES...MAINLY ON TUESDAY
AFTERNOON WHEN SOME MICROBURST POTENTIAL SHOULD EXIST OVER THE S. HAVE
MADE SLIGHT UPWARD ADJUSTMENTS TO MAXES/MINS AT LOCATIONS HAVING THE
LOWER POPS. MEX ENSEMBLE MEAN TEMPS REMAIN STILL SLIGHTLY ABOVE THE
OPERATIONAL RUN VALUES./40/
&&
.AVIATION...EXPECT INCREASING HIGH CLOUDINESS AT ALL TAF SITES FOR
THE REST OF THE EARLY MORNING HOURS...WITH SOME MID LEVEL CLOUDS
MOVING INTO GLH AND GWO. SOME SHOWER OR THUNDERSTORM ACTIVITY WILL
APPROACH GLH AND GWO AROUND OR SHORTLY AFTER 12Z...BUT THAT ACTIVITY
SHOULD BE WEAKENING BY THEN. THE STORMS SHOULD REDEVELOP DURING THE
AFTERNOON HOURS AND CONTINUE TO DROP SOUTHEAST WITH POSSIBLE IMPACT
AT GTR...MEI...AND JAN BEFORE 00Z MONDAY. DUE TO UNCERTAINTY AT THIS
TIME...HAVE KEPT ALL MENTION OF STORMS AT THE AFOREMENTIONED SITES IN
THE VICINITY. THUNDERSTORMS HAVE NOT BEEN MENTIONED AT HBG FOR NOW AS
POSSIBLE IMPACT THERE SHOULD BE AFTER 00Z MONDAY. /DH/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 94 74 88 70 / 29 59 61 29
MERIDIAN 94 71 87 68 / 41 69 64 30
VICKSBURG 95 73 89 69 / 29 50 60 24
HATTIESBURG 99 73 90 72 / 21 33 71 30
NATCHEZ 95 73 88 70 / 20 39 60 30
GREENVILLE 89 71 88 67 / 69 70 28 20
GREENWOOD 88 72 88 68 / 71 68 29 20
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
000
FXUS64 KJAN 050150
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
849 PM CDT SAT JUL 4 2009
.UPDATE...LATE AFTERNOON THUNDERSTORMS AROUND HATTIESBURG OCCURRED
IN AN AREA OF LOW LEVEL CONVERGENCE AIDED BY A WEAK UPPER LEVEL
DISTURBANCE PASSING OVERHEAD. THAT ACTIVITY HAS DISSIPATED LEAVING
THE FORECAST AREA DRY. EXPECT DRY CONDITIONS TO CONTINUE MOST OF THE
NIGHT EXCEPT FOR LATE TONIGHT IN THE FAR NORTHERN FORECAST AREA.
CURRENT ACTIVITY OVER ARKANSAS AND TENNESSEE WILL BE SINKING
SOUTHWARD OVERNIGHT AND MAY IMPACT THE HIGHWAY 82 CORRIDOR TOWARD
DAYBREAK. ANY STORMS THAT IMPACT THE FORECAST AREA WILL BE IN A
WEAKENING STATE.
CURRENT HEAT ADVISORY GOES THROUGH THE NIGHT WITH OVERNIGHT LOWS
EXPECTED TO ONLY DROP INTO THE MID 70S FOLLOWING A DAY OF HIGH HEAT
INDICES.
ONLY CHANGES TO THE FORECAST WERE TO MAKE THE SKY CONDITION PARTLY
CLOUDY AND TO REMOVE MENTION OF RAIN IN THE SOUTH THIS EVENING.
SW
&&
.DISCUSSION...NEAR TERM...VERY SPOTTY SHOWER/TSTM ACTIVITY IS
DEVELOPING ALONG THE HWY 84 CORRIDOR LATE THIS AFTERNOON...BUT IT IS
STRUGGLING AS ANTICYCLONIC FLOW ALOFT AND RELATIVELY DRY AIR
MITIGATE CONVECTIVE POTENTIAL AHEAD OF THE COLD FRONT THAT IS
CURRENTLY MOVING INTO THE OZARK TO MID MS VALLEY REGION. SO DO NOT
EXPECT MUCH COVERAGE NOR FOR THIS ACTIVITY TO LAST MUCH PAST SUNSET.
AS FOR THE HEAT ADVISORY...WILL KEEP IT GOING THROUGH TONIGHT...BUT
EXPECT CLOUDS/PRECIP AND EVENTUALLY DRIER AIR TO REDUCE HEAT STRESS
BEYOND TONIGHT.
FOR SUNDAY AND SUNDAY NIGHT...12Z LOCAL WRF MEMBERS INDICATE THAT A
BROKEN LINE OF SHOWERS/TSTMS COULD APPROACH NORTHERN PORTIONS OF THE
FORECAST AREA BY AROUND SUNRISE TOMORROW AS A CONVECTIVE SYSTEM
ASSOCIATED WITH THE APPROACHING COLD FRONT PROPAGATES SOUTHWARD. IF
COLD-POOLING IS SUFFICIENT...WOULD NOT BE SURPRISED TO SEE THIS LINE
MAKE IT INTO THE FORECAST AREA A LITTLE SOONER. IN ANY CASE...EXPECT
THIS INITIAL CONVECTION MAY FIZZLE OUT AS THE MORNING WEARS ON...BUT
ADDITIONAL CONVECTION WILL FIRE UP QUICKLY BY AFTERNOON AS PRECIP
WATER VALUES INCREASE TO 2+ INCHES IN A MODERATELY UNSTABLE AIRMASS.
0-6KM SHEAR OF 20-30KTS UNDERNEATH THE RIGHT ENTRANCE REGION OF THE
UPPER JET IS EXPECTED OVER NC MS AND THIS WOULD HELP TSTM ORGANIZE
INTO MULTICELLULAR CLUSTERS CAPABLE OF PRODUCING DAMAGING WIND GUSTS
AND HAIL. THE GFS MAY BE A LITTLE TOO AGGRESSIVE IN DEVELOPING
STRONG/ SVR TSTMS SWD INTO SRN PORTIONS OF THE FORECAST AREA BY LATE
SUNDAY AFTN/EVNG AND HAVE GONE WITH A SLIGHTLY SLOWER SOLN IN THE
FORECAST GRIDS. MODEL GUIDANCE CONSENSUS IS FOR THE GREATEST SEVERE
WEATHER POTENTIAL TO RESIDE OVER NORTH CNTRL MS...WITH LESSER RISK
AS YOU GO WWD INTO SE AR/NE LA AND SWD INTO SOUTH CNTRL MS WHERE
LARGE SCALE FORCING WILL BE WEAKER.
FOR MONDAY...MODELS ARE IN GENERAL AGREEMENT THAT A MID LEVEL
SHORTWAVE TROUGH WILL SWING SOUTHEAST THROUGH THE AREA MONDAY. WITH
THE FRONTAL BOUNDARY PUSHING SOUTH TOWARD THE COAST...THE GREATEST
MOISTURE AND INSTABILITY WILL COINCIDE WITH THE TROUGH IN THE AREA
SOUTH OF INTERSTATE 20 AND THAT IS WHERE THE GREATEST POPS ARE
PORTRAYED IN THE GRIDS. AM NOT EXPECTING SEVERE WEATHER TO BE A BIG
CONCERN IF THE GFS/ECMWF/GEFS ARE CORRECT AS THERE WILL BE AN
ABUNDANCE OF CLOUDS/PRECIP AROUND EARLY IN THE DAY THUS LIMITING
DAYTIME HEATING AND DESTABILIZATION. ONCE AGAIN...THE GFS SEEMS A
LITTLE TOO FAST AND HAVE SLOWED DOWN POPS/WEATHER IN THE GRIDS. ON
THE OTHER HAND...THE NAM SEEMS TOO SLOW IN MOVING THE SHORTWAVE
TROUGH THROUGH MONDAY AND CURRENT FORECAST GRIDS ARE CONSIDERABLY
FASTER THAN THAT SOLUTION.
BEYOND MONDAY...HAVE TRIMMED BACK POPS FOR TUES/WED AS IT APPEARS
DRIER AIR WILL WIN OUT FOR AT LEAST A SHORT PERIOD. BY LATE WEEK...A
SHEAR AXIS AND FOCUS FOR MOISTURE MAY ATTEMPT TO SET UP OVER SRN
PORTIONS OF THE AREA AND THE FORECAST IS IN GOOD SHAPE PORTRAYING
LOW POPS THERE. IT STILL LOOKS LIKE THE LONGWAVE PATTERN IS
RETROGRADING FOR THE EXTENDED AND THIS COULD KEEP THE HOTTEST AIR
OUT OF THE FORECAST AREA...BUT HIGHS FORECAST IN THE MID 90S WOULD
STILL BE A FEW DEGREES ABOVE CLIMATIC AVERAGE FOR THIS TIME OF THE
YEAR. /EC/
&&
.FIRE WEATHER...THE LONG STRETCH OF HOT AND DRY WEATHER HAS KEPT AN
INCREASED FIRE DANGER IN PLACE ACROSS THE FORECAST AREA. WHILE SOME
AREAS SAW BRIEF RELIEF WITH RAINFALL LAST WEEKEND...MOST AREAS HAVE
SEEN VERY LITTLE RAIN IN THE PAST 6 TO 8 WEEKS. LOCAL FIRE AGENCIES
CAUTION THAT AN INCREASE IN AGGRESSIVE FIRE BEHAVIOR IS POSSIBLE AND
ANYONE SETTING OFF FIREWORKS SHOULD BE ESPECIALLY VIGILANT. BURN
BANS CONTINUE IN SEVERAL SOUTH MS COUNTIES...INCLUDING HINDS COUNTY.
CHECK THE MFC WEBSITE AT WWW.MFC.STATE.MS.US FOR THE LATEST./40/
&&
.AVIATION...EXPECT HIGH CLOUDINESS ONLY AT ALL TAF SITES TONIGHT.
SOME THUNDERSTORM ACTIVITY WILL APPROACH KGLH AND KGWO AROUND OR
AFTER 12Z SUNDAY BUT THAT ACTIVITY SHOULD BE WEAKENING BY THEN. THE
STORMS SHOULD REDEVELOP DURING THE AFTERNOON HOURS AND CONTINUE TO
DROP SOUTHEAST WITH POSSIBLE IMPACT ALSO AT KGTR AND KJAN BEFORE 00Z
MONDAY. DUE TO UNCERTAINTY...HAVE KEPT ALL MENTION OF STORMS AT THE
AFOREMENTIONED SITES IN THE VICINITY. DO NOT HAVE MENTION OF
THUNDERSTORMS AT KMEI OR KHBG AS POSSIBLE IMPACT AT THOSE STATIONS
SHOULD BE AFTER 00Z MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 76 95 73 89 / 14 34 54 48
MERIDIAN 72 94 72 89 / 12 33 65 51
VICKSBURG 74 95 72 92 / 15 44 44 43
HATTIESBURG 75 96 74 90 / 10 31 52 66
NATCHEZ 76 95 72 90 / 10 40 45 54
GREENVILLE 76 91 70 90 / 49 60 38 22
GREENWOOD 74 88 70 89 / 40 57 42 22
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY UNTIL 7 AM CDT SUNDAY FOR MSZ047-053-054-059>064-
072>074.
LA...HEAT ADVISORY UNTIL 7 AM CDT SUNDAY FOR LAZ007>009-015-016-
023>026.
AR...HEAT ADVISORY UNTIL 7 AM CDT SUNDAY FOR ARZ074-075.
&&
$$
EC/JC/40
000
FXUS64 KJAN 042054
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
354 PM CDT SAT JUL 4 2009
.DISCUSSION...
NEAR TERM...VERY SPOTTY SHOWER/TSTM ACTIVITY IS DEVELOPING ALONG THE HWY
84 CORRIDOR LATE THIS AFTERNOON...BUT IT IS STRUGGLING AS
ANTICYCLONIC FLOW ALOFT AND RELATIVELY DRY AIR MITIGATE CONVECTIVE
POTENTIAL AHEAD OF THE COLD FRONT THAT IS CURRENTLY MOVING INTO THE
OZARK TO MID MS VALLEY REGION. SO DO NOT EXPECT MUCH COVERAGE NOR FOR
THIS ACTIVITY TO LAST MUCH PAST SUNSET. AS FOR THE HEAT ADVISORY...
WILL KEEP IT GOING THROUGH TONIGHT...BUT EXPECT CLOUDS/PRECIP AND
EVENTUALLY DRIER AIR TO REDUCE HEAT STRESS BEYOND TONIGHT.
FOR SUNDAY AND SUNDAY NIGHT...12Z LOCAL WRF MEMBERS INDICATE THAT A
BROKEN LINE OF SHOWERS/TSTMS COULD APPROACH NORTHERN PORTIONS OF THE
FORECAST AREA BY AROUND SUNRISE TOMORROW AS A CONVECTIVE SYSTEM
ASSOCIATED WITH THE APPROACHING COLD FRONT PROPAGATES SOUTHWARD. IF
COLD-POOLING IS SUFFICIENT...WOULD NOT BE SURPRISED TO SEE THIS LINE
MAKE IT INTO THE FORECAST AREA A LITTLE SOONER. IN ANY CASE...EXPECT
THIS INITIAL CONVECTION MAY FIZZLE OUT AS THE MORNING WEARS ON...BUT
ADDITIONAL CONVECTION WILL FIRE UP QUICKLY BY AFTERNOON AS PRECIP
WATER VALUES INCREASE TO 2+ INCHES IN A MODERATELY UNSTABLE AIRMASS.
0-6KM SHEAR OF 20-30KTS UNDERNEATH THE RIGHT ENTRANCE REGION OF THE
UPPER JET IS EXPECTED OVER NC MS AND THIS WOULD HELP TSTM ORGANIZE
INTO MULTICELLULAR CLUSTERS CAPABLE OF PRODUCING DAMAGING WIND GUSTS
AND HAIL. THE GFS MAY BE A LITTLE TOO AGGRESSIVE IN DEVELOPING STRONG/
SVR TSTMS SWD INTO SRN PORTIONS OF THE FORECAST AREA BY LATE
SUNDAY AFTN/EVNG AND HAVE GONE WITH A SLIGHTLY SLOWER SOLN IN THE
FORECAST GRIDS. MODEL GUIDANCE CONSENSUS IS FOR THE GREATEST SEVERE
WEATHER POTENTIAL TO RESIDE OVER NORTH CNTRL MS...WITH LESSER RISK AS
YOU GO WWD INTO SE AR/NE LA AND SWD INTO SOUTH CNTRL MS WHERE LARGE
SCALE FORCING WILL BE WEAKER.
FOR MONDAY...MODELS ARE IN GENERAL AGREEMENT THAT A MID LEVEL
SHORTWAVE TROUGH WILL SWING SOUTHEAST THROUGH THE AREA MONDAY. WITH
THE FRONTAL BOUNDARY PUSHING SOUTH TOWARD THE COAST...THE GREATEST
MOISTURE AND INSTABILITY WILL COINCIDE WITH THE TROUGH IN THE AREA
SOUTH OF INTERSTATE 20 AND THAT IS WHERE THE GREATEST POPS ARE
PORTRAYED IN THE GRIDS. AM NOT EXPECTING SEVERE WEATHER TO BE A BIG
CONCERN IF THE GFS/ECMWF/GEFS ARE CORRECT AS THERE WILL BE AN
ABUNDANCE OF CLOUDS/PRECIP AROUND EARLY IN THE DAY THUS LIMITING
DAYTIME HEATING AND DESTABILIZATION. ONCE AGAIN...THE GFS SEEMS A
LITTLE TOO FAST AND HAVE SLOWED DOWN POPS/WEATHER IN THE GRIDS. ON
THE OTHER HAND...THE NAM SEEMS TOO SLOW IN MOVING THE SHORTWAVE
TROUGH THROUGH MONDAY AND CURRENT FORECAST GRIDS ARE CONSIDERABLY
FASTER THAN THAT SOLUTION.
BEYOND MONDAY...HAVE TRIMMED BACK POPS FOR TUES/WED AS IT APPEARS
DRIER AIR WILL WIN OUT FOR AT LEAST A SHORT PERIOD. BY LATE WEEK...A
SHEAR AXIS AND FOCUS FOR MOISTURE MAY ATTEMPT TO SET UP OVER SRN
PORTIONS OF THE AREA AND THE FORECAST IS IN GOOD SHAPE PORTRAYING
LOW POPS THERE. IT STILL LOOKS LIKE THE LONGWAVE PATTERN IS
RETROGRADING FOR THE EXTENDED AND THIS COULD KEEP THE HOTTEST AIR
OUT OF THE FORECAST AREA...BUT HIGHS FORECAST IN THE MID 90S WOULD
STILL BE A FEW DEGREES ABOVE CLIMATIC AVERAGE FOR THIS TIME OF THE
YEAR. /EC/
&&
.FIRE WEATHER...THE LONG STRETCH OF HOT AND DRY WEATHER HAS KEPT AN
INCREASED FIRE DANGER IN PLACE ACROSS THE FORECAST AREA. WHILE SOME
AREAS SAW BRIEF RELIEF WITH RAINFALL LAST WEEKEND...MOST AREAS HAVE
SEEN VERY LITTLE RAIN IN THE PAST 6 TO 8 WEEKS. LOCAL FIRE AGENCIES
CAUTION THAT AN INCREASE IN AGGRESSIVE FIRE BEHAVIOR IS POSSIBLE AND
ANYONE SETTING OFF FIREWORKS SHOULD BE ESPECIALLY VIGILANT. BURN
BANS CONTINUE IN SEVERAL SOUTH MS COUNTIES...INCLUDING HINDS COUNTY.
CHECK THE MFC WEBSITE AT WWW.MFC.STATE.MS.US FOR THE LATEST./40/
&&
.AVIATION...HAVE MAINTAINED VFR CONDITIONS THROUGH SUNDAY MORNING
FOR ALL TAF SITES. NEAR THE END OF THE VALID PERIOD...PERIODS OF
SHRA AND TSRA WILL BE POSSIBLE DURING THE DAY ON SUNDAY...WITH THE
HIGHEST COVERAGE IN THE VICINITY OF GLH...GWO...AND GTR. JC
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 76 95 73 89 / 14 34 54 48
MERIDIAN 72 94 72 89 / 12 33 65 51
VICKSBURG 74 95 72 92 / 15 44 44 43
HATTIESBURG 75 96 74 90 / 10 31 52 66
NATCHEZ 76 95 72 90 / 10 40 45 54
GREENVILLE 76 91 70 90 / 49 60 38 22
GREENWOOD 74 88 70 89 / 40 57 42 22
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY UNTIL 7 AM CDT SUNDAY FOR MSZ047-053-054-059>064-
072>074.
LA...HEAT ADVISORY UNTIL 7 AM CDT SUNDAY FOR LAZ007>009-015-016-
023>026.
AR...HEAT ADVISORY UNTIL 7 AM CDT SUNDAY FOR ARZ074-075.
&&
$$
EC/JC/40
000
FXUS64 KJAN 041451 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE JACKSON MS
945 AM CDT SAT JUL 4 2009
.DISCUSSION...
UPDATE: THE LOW-MID LEVEL RIDGE IS CENTERED OVER THE FORECAST AREA
THIS MORNING KEEPING THE AREA SUNNY AND THIS HAS ALLOWED
TEMPERATURES TO RISE A LITTLE FASTER THAN FORECAST...BUT AFTN
FORECAST HIGHS ARE IN GOOD SHAPE. LATEST NAM AND LOCAL WRF GUIDANCE
INDICATE A FEW SHOWERS COULD DEVELOP DURING MAX HEATING ALONG THE
HWY 84 CORRIDOR IN RESPONSE TO A SUBTLE UPPER LEVEL SHEAR AXIS AND
MAY NEED TO ADD MENTION OF THIS TO GRIDS. OTHERWISE...ALL IS ON
TRACK WITH THE FORECAST AND THE HEAT ADVISORY IS IN GOOD SHAPE. /EC/
PREVIOUS FORECAST...
SHORT TERM...WE WILL HAVE ANOTHER DAY OF ABOVE NORMAL TEMPERATURES
TO DEAL WITH FOR INDEPENDENCE DAY THROUGHOUT THE CWA WITH A STRONG
RIDGE OF HIGH PRESSURE NOSING IN FROM THE SOUTHERN PLAINS. IT
SHOULD ALSO BE ANOTHER DRY DAY WITH PLENTY OF SUBSIDENCE AND THE
STORM TRACK REMAINING WELL NORTH OF THE AREA. THERE WILL BE AN
INCREASE IN HUMIDITY COMPARED TO YESTERDAY AS WINDS TURN TO A MORE
SW DIRECTION...ESPECIALLY WEST OF I-55. THIS WILL MAKE FOR QUITE AN
UNCOMFORTABLE DAY TO BE OUTDOORS...ESPECIALLY DURING THE AFTERNOON
HOURS. A HEAT ADVISORY HAS BEEN ISSUED FOR AREAS WEST OF A LINE
FROM GREENVILLE...TO VICKSBURG...TO HATTIESBURG FOR EXPECTED HEAT
INDICES OF 105 DEGREES AND OVERNIGHT LOWS IN THE MID 70S. GUIDANCE
TEMPERATURES LOOKED GOOD FOR MOST PLACES...EXCEPT FOR THE HBG
VICINITY WHERE VALUES WERE RAISED A FEW DEGREES GIVEN THE RECENT
STRETCH OF VERY HOT WEATHER THERE. BY SATURDAY NIGHT...A FRONTAL
BOUNDARY WILL BEGIN MOVING CLOSER TO THE NORTHERN CWA BORDER WITH
SLIGHT CHANCE POPS DURING THE OVERNIGHT PERIOD...BUT MOST CENTRAL
AND SOUTHERN ZONES SHOULD REMAIN DRY.
BY SUNDAY...RAIN CHANCES DEFINITELY INCREASE OVER THE CWA AS THE
BOUNDARY MOVES FURTHER SOUTH. ALL MODELS SHOW THIS...AND THE BEST
CHANCES ARE FOR THE NORTHERN 2/3RDS OF THE AREA. SPC HAS EVEN
HIGHLIGHTED A SLIGHT RISK OF SEVERE WEATHER FOR SUNDAY GIVEN THAT WE
WILL BE IN THE RIGHT ENTRANCE REGION OF AN 80KT 250MB JET...30KT
850MB WINDS...AND LOWER 70F DEWPOINTS NEAR A LOW LEVEL CONVERGENCE
ZONE. THIS POTENTIAL WILL BE MENTIONED IN THE HWO. MAV TEMP
GUIDANCE SEEMED A LITTLE ON THE LOW SIDE THIS RUN...ESPECIALLY
ACROSS THE NORTHERN HALF...SO HIGHS WERE RAISED SEVERAL DEGREES FOR
HIGHS TO BE MORE IN LINE WITH THE HIGHER NAM VALUES. OVERNIGHT LOWS
APPEARED GOOD AND NO SIGNIFICANT CHANGES WERE WARRANTED
THERE...EXCEPT FOR HKS WHERE LOWS WERE RAISED A FEW DEGREES TO
ACCOUNT FOR THE URBAN HEAT ISLAND EFFECT. /DH/
LONG TERM...MODELS SEEM IN DECENT AGREEMENT THAT THE LONGWAVE PATTERN
WILL FINALLY RETROGRADE FOR THE MONDAY THROUGH FRIDAY TIME FRAME. THE
RECENT UPPER RIDGE BUILDS WWD INTO NM BY MID WEEK WHICH ALLOWS A
STALLED SURFACE FRONTAL ZONE TO REMAIN IN PLACE ALONG THE GULF COAST
FOR AT LEAST THE FIRST HALF OF THE WEEK. THIS BOUNDARY WILL HAVE
DAILY INTERACTIONS WITH ANY SEA BREEZE ACTION AND A WEAK UPPER TROUGH
AXIS ALSO LINGERS ACROSS THE LOWER MS VALLEY WHICH SHOULD PROVIDE THE
ADDITIONAL CLOUD COVER WE NEED TO HOLD TEMPS CLOSER TO NORMALS FOR
THIS TIME OF YEAR. BOTH THE ECMWF AND GFS RUNS SUPPORT 1 TO 2 INCH
RAINFALL TOTALS FOR LOCATIONS S OF INTERSTATE 20 BY THE END OF THE
WEEK WHICH WOULD BE VERY MUCH WELCOMED. THERE ARE ALSO SOME HINTS AT
A CUTOFF UPPER LOW CENTER FORMING IN SERN LA BY EITHER THURSDAY OR
FRIDAY ON THE OPERATIONAL MODEL RUNS. HOWEVER... THERE IS LESS
SUPPORT FOR THIS IDEA IN THE GFS ENSEMBLE MEANS SO WE`LL HAVE TO
MONITOR FUTURE RUNS.
THE TROPICS APPEAR TO REMAIN QUIET FOR THE UPCOMING WEEK WITH ANY
POTENTIAL DEVELOPMENT CONFINED TO THE EPAC. AT ANY RATE...THE BEST
POPS WILL BE HELD OVER THE SRN PORTIONS OF THE CWFA DURING THE ENTIRE
WEEK WITH A PUSH NWD BY FRIDAY. TEMPS SHOULD RETURN CLOSER TO NORMALS
AT LOCATIONS WITH THE BEST RAIN CHANCES... ESPECIALLY DURING THE
FIRST HALF OF THE WEEK. HAVE MADE SLIGHT UPWARD ADJUSTMENTS TO
MAXES/MINS AT LOCATIONS WITH LOWER POPS AS MEX ENSEMBLE MEAN NUMBERS
ABOVE THE OPERATIONAL RUN VALUES./40/
&&
.FIRE WEATHER...THE LONG STRETCH OF HOT AND DRY WEATHER HAS KEPT AN
INCREASED FIRE DANGER IN PLACE ACROSS THE FORECAST AREA. WHILE SOME
AREAS SAW BRIEF RELIEF WITH RAINFALL LAST WEEKEND...MOST AREAS HAVE
SEEN VERY LITTLE RAIN IN THE PAST 6 TO 8 WEEKS. LOCAL FIRE AGENCIES
CAUTION THAT AN INCREASE IN AGGRESSIVE FIRE BEHAVIOR IS POSSIBLE AND
ANYONE SETTING OFF FIREWORKS SHOULD BE ESPECIALLY VIGILANT. BURN
BANS CONTINUE IN SEVERAL SOUTH MS COUNTIES...INCLUDING HINDS COUNTY.
CHECK THE MFC WEBSITE AT WWW.MFC.STATE.MS.US FOR THE LATEST./40/
&&
.AVIATION...ONLY HIGH CIRRUS AND A FEW AFTERNOON CUMULUS CLOUDS ARE
EXPECTED ACROSS ALL TAF SITES THROUGH TODAY ALONG WITH LIGHT WINDS.
THUS...HAVE MAINTAINED VFR CONDITIONS THROUGH 00Z SUNDAY FOR ALL TAF
SITES. BEYOND THE TAF VALID PERIOD...PERIODS OF SHRA AND TSRA WILL BE
POSSIBLE DURING THE DAY ON SUNDAY...WITH THE HIGHEST COVERAGE IN THE
VICINITY OF GLH...GWO...AND GTR. /DH/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT CDT TONIGHT
FOR MSZ047-053-054-059>064-072>074.
LA...HEAT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT CDT TONIGHT
FOR LAZ007>009-015-016-023>026.
AR...HEAT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT CDT TONIGHT
FOR ARZ074-075.
&&
$$
000
FXUS64 KJAN 040859
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
359 AM CDT SAT JUL 4 2009
.SHORT TERM...WE WILL HAVE ANOTHER DAY OF ABOVE NORMAL TEMPERATURES
TO DEAL WITH FOR INDEPENDENCE DAY THROUGHOUT THE CWA WITH A STRONG
RIDGE OF HIGH PRESSURE NOSING IN FROM THE SOUTHERN PLAINS. IT
SHOULD ALSO BE ANOTHER DRY DAY WITH PLENTY OF SUBSIDENCE AND THE
STORM TRACK REMAINING WELL NORTH OF THE AREA. THERE WILL BE AN
INCREASE IN HUMIDITY COMPARED TO YESTERDAY AS WINDS TURN TO A MORE
SW DIRECTION...ESPECIALLY WEST OF I-55. THIS WILL MAKE FOR QUITE AN
UNCOMFORTABLE DAY TO BE OUTDOORS...ESPECIALLY DURING THE AFTERNOON
HOURS. A HEAT ADVISORY HAS BEEN ISSUED FOR AREAS WEST OF A LINE
FROM GREENVILLE...TO VICKSBURG...TO HATTIESBURG FOR EXPECTED HEAT
INDICES OF 105 DEGREES AND OVERNIGHT LOWS IN THE MID 70S. GUIDANCE
TEMPERATURES LOOKED GOOD FOR MOST PLACES...EXCEPT FOR THE HBG
VICINITY WHERE VALUES WERE RAISED A FEW DEGREES GIVEN THE RECENT
STRETCH OF VERY HOT WEATHER THERE. BY SATURDAY NIGHT...A FRONTAL
BOUNDARY WILL BEGIN MOVING CLOSER TO THE NORTHERN CWA BORDER WITH
SLIGHT CHANCE POPS DURING THE OVERNIGHT PERIOD...BUT MOST CENTRAL
AND SOUTHERN ZONES SHOULD REMAIN DRY.
BY SUNDAY...RAIN CHANCES DEFINITELY INCREASE OVER THE CWA AS THE
BOUNDARY MOVES FURTHER SOUTH. ALL MODELS SHOW THIS...AND THE BEST
CHANCES ARE FOR THE NORTHERN 2/3RDS OF THE AREA. SPC HAS EVEN
HIGHLIGHTED A SLIGHT RISK OF SEVERE WEATHER FOR SUNDAY GIVEN THAT WE
WILL BE IN THE RIGHT ENTRANCE REGION OF AN 80KT 250MB JET...30KT
850MB WINDS...AND LOWER 70F DEWPOINTS NEAR A LOW LEVEL CONVERGENCE
ZONE. THIS POTENTIAL WILL BE MENTIONED IN THE HWO. MAV TEMP
GUIDANCE SEEMED A LITTLE ON THE LOW SIDE THIS RUN...ESPECIALLY
ACROSS THE NORTHERN HALF...SO HIGHS WERE RAISED SEVERAL DEGREES FOR
HIGHS TO BE MORE IN LINE WITH THE HIGHER NAM VALUES. OVERNIGHT LOWS
APPEARED GOOD AND NO SIGNIFICANT CHANGES WERE WARRANTED THERE...EXCEPT
FOR HKS WHERE LOWS WERE RAISED A FEW DEGREES TO ACCOUNT FOR THE URBAN
HEAT ISLAND EFFECT. /DH/
.LONG TERM...MODELS SEEM IN DECENT AGREEMENT THAT THE LONGWAVE PATTERN
WILL FINALLY RETROGRADE FOR THE MONDAY THROUGH FRIDAY TIME FRAME. THE
RECENT UPPER RIDGE BUILDS WWD INTO NM BY MID WEEK WHICH ALLOWS A
STALLED SURFACE FRONTAL ZONE TO REMAIN IN PLACE ALONG THE GULF COAST
FOR AT LEAST THE FIRST HALF OF THE WEEK. THIS BOUNDARY WILL HAVE
DAILY INTERACTIONS WITH ANY SEA BREEZE ACTION AND A WEAK UPPER TROUGH
AXIS ALSO LINGERS ACROSS THE LOWER MS VALLEY WHICH SHOULD PROVIDE THE
ADDITIONAL CLOUD COVER WE NEED TO HOLD TEMPS CLOSER TO NORMALS FOR
THIS TIME OF YEAR. BOTH THE ECMWF AND GFS RUNS SUPPORT 1 TO 2 INCH
RAINFALL TOTALS FOR LOCATIONS S OF INTERSTATE 20 BY THE END OF THE
WEEK WHICH WOULD BE VERY MUCH WELCOMED. THERE ARE ALSO SOME HINTS AT
A CUTOFF UPPER LOW CENTER FORMING IN SERN LA BY EITHER THURSDAY OR
FRIDAY ON THE OPERATIONAL MODEL RUNS. HOWEVER... THERE IS LESS
SUPPORT FOR THIS IDEA IN THE GFS ENSEMBLE MEANS SO WE`LL HAVE TO
MONITOR FUTURE RUNS.
THE TROPICS APPEAR TO REMAIN QUIET FOR THE UPCOMING WEEK WITH ANY
POTENTIAL DEVELOPMENT CONFINED TO THE EPAC. AT ANY RATE...THE BEST
POPS WILL BE HELD OVER THE SRN PORTIONS OF THE CWFA DURING THE ENTIRE
WEEK WITH A PUSH NWD BY FRIDAY. TEMPS SHOULD RETURN CLOSER TO NORMALS
AT LOCATIONS WITH THE BEST RAIN CHANCES... ESPECIALLY DURING THE FIRST
HALF OF THE WEEK. HAVE MADE SLIGHT UPWARD ADJUSTMENTS TO MAXES/MINS
AT LOCATIONS WITH LOWER POPS AS MEX ENSEMBLE MEAN NUMBERS ABOVE THE
OPERATIONAL RUN VALUES./40/
&&
.FIRE WEATHER...THE LONG STRETCH OF HOT AND DRY WEATHER HAS KEPT AN
INCREASED FIRE DANGER IN PLACE ACROSS THE FORECAST AREA. WHILE SOME
AREAS SAW BRIEF RELIEF WITH RAINFALL LAST WEEKEND...MOST AREAS HAVE
SEEN VERY LITTLE RAIN IN THE PAST 6 TO 8 WEEKS. LOCAL FIRE AGENCIES
CAUTION THAT AN INCREASE IN AGGRESSIVE FIRE BEHAVIOR IS POSSIBLE AND
ANYONE SETTING OFF FIREWORKS SHOULD BE ESPECIALLY VIGILANT. BURN
BANS CONTINUE IN SEVERAL SOUTH MS COUNTIES...INCLUDING HINDS COUNTY.
CHECK THE MFC WEBSITE AT WWW.MFC.STATE.MS.US FOR THE LATEST./40/
&&
.AVIATION...ONLY HIGH CIRRUS AND A FEW AFTERNOON CUMULUS CLOUDS ARE
EXPECTED ACROSS ALL TAF SITES THROUGH TODAY ALONG WITH LIGHT WINDS.
THUS...HAVE MAINTAINED VFR CONDITIONS THROUGH 00Z SUNDAY FOR ALL TAF
SITES. BEYOND THE TAF VALID PERIOD...PERIODS OF SHRA AND TSRA WILL BE
POSSIBLE DURING THE DAY ON SUNDAY...WITH THE HIGHEST COVERAGE IN THE
VICINITY OF GLH...GWO...AND GTR. /DH/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 98 75 91 73 / 4 9 32 28
MERIDIAN 97 71 92 72 / 4 10 32 27
VICKSBURG 98 74 90 72 / 4 9 32 28
HATTIESBURG 100 74 97 75 / 4 3 20 22
NATCHEZ 96 74 93 73 / 4 7 22 22
GREENVILLE 99 76 88 70 / 4 20 51 29
GREENWOOD 97 75 87 69 / 4 20 51 29
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT CDT TONIGHT
FOR MSZ047-053-054-059>064-072>074.
LA...HEAT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT CDT TONIGHT
FOR LAZ007>009-015-016-023>026.
AR...HEAT ADVISORY FROM 10 AM THIS MORNING TO MIDNIGHT CDT TONIGHT
FOR ARZ074-075.
&&
$$
000
FXUS64 KJAN 040151
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
850 PM CDT FRI JUL 3 2009
.UPDATE...MID LEVEL RIDGE REMAINS IN PLACE ACROSS TEXAS THIS EVENING
WITH PLENTY OF HIGH LEVEL CLOUDINESS SPILLING OVER THE RIDGE INTO
THE FORECAST AREA. SURFACE HIGH PRESSURE WAS CENTERED OVER THE
TENNESSEE VALLEY WITH A LIGHT NORTH FLOW IN PLACE.
DRIER SURFACE AIR IN PLACE ACROSS EASTERN MISSISSIPPI WILL ALLOW
OVERNIGHT TEMPERATURES TO FALL INTO THE MIDDLE TO UPPER 60S THERE
WHILE A MORE HUMID AIR MASS TO THE WEST WILL KEEP MORNING READINGS
IN THE LOWER 70S.
CURRENT GRIDS AND TEXT FORECASTS IN GOOD SHAPE AND ONLY CHANGE WAS
TO CUT OVERNIGHT POPS TO ZERO IN THE GRIDS.
SW
&&
.DISCUSSION...TONIGHT THROUGH SUNDAY NIGHT...THE FIRST HALF OF THE
INDEPENDENCE DAY WEEKEND LOOKS TO BE DRY...ALBEIT WARM. UPPER 594DM
RIDGE REMAINS CENTERED ACROSS CENTRAL TEXAS AND ITS INFLUENCE
EXTENDS ACROSS OUR REGION. SOME RESIDUAL CLOUD COVER FROM
DISTURBANCE UPSTREAM BUT THIS IS NOT AFFECTING TEMPS TOO BADLY AS
READINGS HAVE BEEN ABLE TO CLIMB INTO THE MID TO UPPER 90S AT MOST
LOCATIONS.
CONDITIONS WILL BE SIMILAR FOR THE NEXT 24 HOURS AS THE RIDGE
REMAINS IN CONTROL OF OUR WEATHER. LOWS TONIGHT WILL AGAIN FALL INTO
THE UPPER 60S (ACROSS THE EAST WHERE THE DRIER AIR LOOKS TO RESIDE)
AND LOWER 70S AS WE HANG ONTO NORTHERLY FLOW AND DRIER AIR FOR JUST
A BIT LONGER. A DRY DAY WILL BE ON TAP FOR 4TH OF JULY ACTIVITIES
ACROSS THE AREA. HOWEVER...IT WILL BE ANOTHER WARM DAY. AS FLOW
BECOMES SOUTHERLY...AN INCREASE IN MOISTURE WILL COMMENCE ACROSS THE
AREA AND BRING A RETURN OF THE UPPER 60S AND LOWER 70 DEWPOINTS TO
THE REGION. WITH TEMPERATURES IN THE UPPER 90S TO AROUND 100...AND
INCREASING DEWPOINTS...UNCOMFORTABLE HUMIDITY WILL RETURN TO THE
REGION. HEAT INDICES WILL REACH UP TO 105 AND POSSIBLY HIGHER. WILL
KEEP MENTION OF THIS IN THE HWO FOR POSSIBLE HEAT ADVISORY
CONSIDERATION AND FOR RESIDENTS TO WATCH PROLONGED OUTSIDE EXPOSURE
DURING PEAK HEATING.
BY LATE SATURDAY NIGHT INTO SUNDAY...THE UPPER LOW JUST NORTHEAST OF
THE GREAT LAKES REGION STARTS TO MOVE OFF TO THE EAST AND DRAGS A
COLD FRONT TOWARDS THE CWA. THIS BREAKS DOWN THE UPPER RIDGE AND
WILL BRING RAIN CHANCES BACK TO THE REGION FOR SUNDAY AND SUNDAY
NIGHT. NAM IS THE FASTEST WITH THE FRONT MOVING THROUGH ENTIRELY ON
SUNDAY. HOWEVER...THE ECMWF IS SLOWER AND DEFINITELY WETTER THAN THE
NAM AND GFS. SO HAVE KEPT WITH THIS SOLUTION A LITTLE MORE. THERE
WILL ALSO BE A CHANCE FOR SOME STRONG TO SEVERE STORMS...ESPECIALLY
IN THE NORTH SUNDAY AFTERNOON AND EVENING AS THIS FRONT WILL COMBINE
WITH A VERY MOIST (PWATS AROUND 1.8-2.0 INCHES) AND UNSTABLE AIRMASS
(MLCAPES OF 1700-2000 J/KG) WILL INCLUDE MENTION OF THIS THREAT IN
THE HWO.
OVERALL...GUIDANCE CAME IN PRETTY GOOD FOR BOTH POPS AND TEMPS. LOWS
WILL STEADILY INCREASE AS MOISTURE INCREASES AHEAD OF IMPENDING
FROPA. HIGHS WILL BE WARM AGAIN ON SATURDAY BUT WITH THE CLOUDS AND
RAIN ASSOCIATED WITH THE FRONT ON SUNDAY...TEMPS SHOULD BE MORE
SEASONAL. WENT WITH GUIDANCE ON TEMPS. POPS WERE DRY THROUGH
SATURDAY. SLIGHT CHANCES COME IN FOR THE NORTH ON SATURDAY NIGHT AND
HIGHER POPS IN FOR SUNDAY AND SUNDAY NIGHT. THESE WERE GENERALLY
ACCEPTED BUT DID RAISE SOME IN THE NORTH...CLOSER TO THE FRONT.
MONDAY THROUGH FRIDAY...BOTH THE GFS AND ECMWF HANG THE FRONT AROUND
THE CWA...OR JUST TO THE SOUTH THROUGH THE PERIOD WITH A FEW
DISTURBANCES ROAMING ALONG THE FRONT. THIS SHOULD KEEP AT LEAST SOME
RAIN CHANCES FOR THE REGION THROUGH THE PERIOD. NEAR THE END OF THE
EXTENDED...THE GFS BUILDS IN A LARGE UPPER RIDGE...SO THE HEAT MAY
SLOWLY BE RETURNING FOR THE END OF THE WEEK INTO THE WEEKEND.
HOWEVER...WITH THE FRONT HANGING AROUND UNTIL THEN...TEMPS SHOULD
REMAIN ON THE NORMAL SIDE...IN THE LOW TO MID 90S. /28/
&&
.AVIATION...ONLY HIGH CLOUDINESS EXPECTED ACROSS THE AREA TONIGHT
ALONG WITH LIGHT WINDS. THUS...HAVE MAINTAINED VFR CONDITIONS
THROUGH 00Z SUNDAY FOR ALL TAF SITES.
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 70 99 75 94 / 4 6 6 20
MERIDIAN 65 97 75 94 / 4 8 7 20
VICKSBURG 71 99 75 94 / 4 5 7 22
HATTIESBURG 70 99 76 95 / 12 4 7 14
NATCHEZ 72 98 75 92 / 12 3 9 14
GREENVILLE 73 99 75 91 / 5 6 14 37
GREENWOOD 68 98 73 92 / 4 8 11 37
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
28/EC
000
FXUS64 KJAN 032032
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
332 PM CDT FRI JUL 3 2009
.DISCUSSION...TONIGHT THROUGH SUNDAY NIGHT...THE FIRST HALF OF THE
INDEPENDENCE DAY WEEKEND LOOKS TO BE DRY...ALBEIT WARM. UPPER 594DM
RIDGE REMAINS CENTERED ACROSS CENTRAL TEXAS AND ITS INFLUENCE
EXTENDS ACROSS OUR REGION. SOME RESIDUAL CLOUD COVER FROM
DISTURBANCE UPSTREAM BUT THIS IS NOT AFFECTING TEMPS TOO BADLY AS
READINGS HAVE BEEN ABLE TO CLIMB INTO THE MID TO UPPER 90S AT MOST
LOCATIONS.
CONDITIONS WILL BE SIMILAR FOR THE NEXT 24 HOURS AS THE RIDGE
REMAINS IN CONTROL OF OUR WEATHER. LOWS TONIGHT WILL AGAIN FALL INTO
THE UPPER 60S (ACROSS THE EAST WHERE THE DRIER AIR LOOKS TO RESIDE)
AND LOWER 70S AS WE HANG ONTO NORTHERLY FLOW AND DRIER AIR FOR JUST
A BIT LONGER. A DRY DAY WILL BE ON TAP FOR 4TH OF JULY ACTIVITIES
ACROSS THE AREA. HOWEVER...IT WILL BE ANOTHER WARM DAY. AS FLOW
BECOMES SOUTHERLY...AN INCREASE IN MOISTURE WILL COMMENCE ACROSS THE
AREA AND BRING A RETURN OF THE UPPER 60S AND LOWER 70 DEWPOINTS TO
THE REGION. WITH TEMPERATURES IN THE UPPER 90S TO AROUND 100...AND
INCREASING DEWPOINTS...UNCOMFORTABLE HUMIDITY WILL RETURN TO THE
REGION. HEAT INDICES WILL REACH UP TO 105 AND POSSIBLY HIGHER. WILL
KEEP MENTION OF THIS IN THE HWO FOR POSSIBLE HEAT ADVISORY
CONSIDERATION AND FOR RESIDENTS TO WATCH PROLONGED OUTSIDE EXPOSURE
DURING PEAK HEATING.
BY LATE SATURDAY NIGHT INTO SUNDAY...THE UPPER LOW JUST NORTHEAST OF
THE GREAT LAKES REGION STARTS TO MOVE OFF TO THE EAST AND DRAGS A
COLD FRONT TOWARDS THE CWA. THIS BREAKS DOWN THE UPPER RIDGE AND
WILL BRING RAIN CHANCES BACK TO THE REGION FOR SUNDAY AND SUNDAY
NIGHT. NAM IS THE FASTEST WITH THE FRONT MOVING THROUGH ENTIRELY ON
SUNDAY. HOWEVER...THE ECMWF IS SLOWER AND DEFINITELY WETTER THAN THE
NAM AND GFS. SO HAVE KEPT WITH THIS SOLUTION A LITTLE MORE. THERE
WILL ALSO BE A CHANCE FOR SOME STRONG TO SEVERE STORMS...ESPECIALLY
IN THE NORTH SUNDAY AFTERNOON AND EVENING AS THIS FRONT WILL COMBINE
WITH A VERY MOIST (PWATS AROUND 1.8-2.0 INCHES) AND UNSTABLE AIRMASS
(MLCAPES OF 1700-2000 J/KG) WILL INCLUDE MENTION OF THIS THREAT IN
THE HWO.
OVERALL...GUIDANCE CAME IN PRETTY GOOD FOR BOTH POPS AND TEMPS. LOWS
WILL STEADILY INCREASE AS MOISTURE INCREASES AHEAD OF IMPENDING
FROPA. HIGHS WILL BE WARM AGAIN ON SATURDAY BUT WITH THE CLOUDS AND
RAIN ASSOCIATED WITH THE FRONT ON SUNDAY...TEMPS SHOULD BE MORE
SEASONAL. WENT WITH GUIDANCE ON TEMPS. POPS WERE DRY THROUGH
SATURDAY. SLIGHT CHANCES COME IN FOR THE NORTH ON SATURDAY NIGHT AND
HIGHER POPS IN FOR SUNDAY AND SUNDAY NIGHT. THESE WERE GENERALLY
ACCEPTED BUT DID RAISE SOME IN THE NORTH...CLOSER TO THE FRONT.
MONDAY THROUGH FRIDAY...BOTH THE GFS AND ECMWF HANG THE FRONT AROUND
THE CWA...OR JUST TO THE SOUTH THROUGH THE PERIOD WITH A FEW
DISTURBANCES ROAMING ALONG THE FRONT. THIS SHOULD KEEP AT LEAST SOME
RAIN CHANCES FOR THE REGION THROUGH THE PERIOD. NEAR THE END OF THE EXTENDED...THE
GFS BUILDS IN A LARGE UPPER RIDGE...SO THE HEAT MAY SLOWLY BE
RETURNING FOR THE END OF THE WEEK INTO THE WEEKEND. HOWEVER...WITH THE FRONT
HANGING AROUND UNTIL THEN...TEMPS SHOULD REMAIN ON THE NORMAL SIDE...IN
THE LOW TO MID 90S. /28/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH SATURDAY NIGHT. ISOLATED TSTM
ACTIVITY WILL BE POSSIBLE LATE SAT AFTN WITH ONLY A REMOTE CHANCE OF
THIS IMPACTING A TAF SITE. A COLD FRONT WILL APPROACH LATE SUNDAY
INTO SUNDAY NIGHT AND TSTMS ARE EXPECTED TO BE MORE PREVALENT THEN.
/EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 70 99 75 94 / 4 6 6 20
MERIDIAN 65 97 75 94 / 4 8 7 20
VICKSBURG 71 99 75 94 / 4 5 7 22
HATTIESBURG 70 99 76 95 / 12 4 7 14
NATCHEZ 72 98 75 92 / 12 3 9 14
GREENVILLE 73 99 75 91 / 5 6 14 37
GREENWOOD 68 98 73 92 / 4 8 11 37
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
28/EC
| 
