000 FXUS61 KAKQ 100946 AFDAKQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 446 AM EST FRI FEB 10 2012 .SYNOPSIS... HIGH PRESSURE MOVES OFF THE COAST TODAY...AS LOW PRESSURE DEVELOPS OVER THE GULF OF MEXICO. THIS LOW WILL STRENGTHEN TONIGHT AS IT TRACKS NORTHEAST ALONG THE COASTAL CAROLINAS...THEN PUSHES OFF TO THE NORTHEAST OF THE AREA ON SATURDAY. A STRONG COLD FRONT WILL CROSS THE REGION SATURDAY AFTERNOON AND EVENING...FOLLOWED BY ARCTIC HIGH PRESSURE BUILDING INTO THE AREA SUNDAY AND MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SEASONABLY COLD EARLY THIS MORNING ACRS THE MID ATLC...SKIES ARE MAINLY CLEAR ASIDE FROM SOME HIGH CLOUDINESS. LOOKING AT IR/WV SATELLITE REVEALS THAT RATHER QUICK CHANGES WILL BE ON THE WAY LATER TODAY...AND ESPECIALLY TONIGHT. STILL A QUIET PATTERN TODAY...INCREASING CLOUDS CAN BE EXPECTED ALL AREAS LATER THIS MORNING AND BY MID AFTN SKIES WILL TEND TO AVG OUT MOSTLY CLOUDY. BULK OF FORCING AND LOW LEVEL MOISTURE WILL STAY JUST OFF TO OUR SW HOWEVER...SO WILL KEEP FCST DRY TODAY. MODERATE SW FLOW GETS GOING THIS AFTN SO EVEN W/ CLOUDS SHOULD SEE HIGHS CLOSE TO MAV/MET NUMBERS...MID-UPR 50S SOUTH TO AROUND 50 FAR NORTH. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... FIRST STAGE IN A TWO-PART EVENT BEGINS THIS EVENING AS SOUTHERN STREAM SHORTWAVE PUSHES ACRS THE GULF COAST STATES AND OFF THE COAST OF NORTHERN FLORIDA. SFC LOW PRESSURE RAPIDLY DEEPENS ALONG THE NC/SC COAST BY 06Z/SAT...AND MODELS IN GOOD AGREEMENT THAT IT WILL BE JUST OFF THE SE VA/NC COAST BY 12Z/SAT. DECENT FORCING DEVELOPS AS EARLY AS 01-03Z THIS EVENING ACRS NE NC...PEAKS/FOCUSES ACRS SE ZONES BETWEEN 03-09Z. WILL CONTINUE W/ CAT POPS DURING THIS TIMEFRAME IN THE SE...WITH HIGH CHC TO LIKELY POPS ELSEWHERE. QPF AMOUNTS WILL BE FAIRLY LIGHT EXCEPT IN THE SE ZONES WHERE ABOUT 0.50" WILL BE POSSIBLE. STILL LOOKS LIKE ALL RAIN AS PTYPE TONIGHT...ALTHOUGH MAY NEED TO WATCH FOR A LIGHT RA/SN MIX IN EXTREME NW ZONES (WOULD BE VERY LIGHT IF IT DID OCCUR AND W/ TEMPS ABOVE 32 F/NO IMPACTS). LOWS RANGING FROM THE MID 30S NW PIEDMONT TO 40-45 SE VA/NE NC. SAT...EVOLUTION OF THIS SYSTEM HAS GENLY REMAINED SIMILAR OVER THE PAST FEW MODEL RUNS...STILL TOO PROGRESSIVE FOR PHASING OF THE NORTHERN AND SOUTHERN STREAM MID/UPR LEVEL FLOW. THE SFC LOW AND MAIN PRECIP SHIELD SHOULD ALREADY BE EXITING THE AREA BY DAYBREAK SAT...ALTHOUGH SOME SPOTTY -RA/DZ AND CLOUDS WILL LINGER. AS PREVIOUS SHIFTS NOTED...LOOKS LIKE A LULL FOR MID MORNING THROUGH EARLY-MID AFTN AHEAD OF TH APPROACHING NRN STREAM SHORTWAVE AND HAVE KEPT POPS AT OR BELOW 20%. STILL A LOT OF MSTR FOR MORE CLOUDS THAN SUN ALTHOUGH SOME BREAKS WILL BE POSSIBLE SRN 1/2. TEMPS LOOK TO WARM INTO THE MID-UPR 40S N...LWR 50S FAR S. WITH SUBTLE DIFFERENCES...NAM/GFS AND ECMWF FOR THAT MATTER...SHOW STRONG DESTABILIZATION OF THE ATMOSPHERE BETWEEN 21Z-03Z. DEEPEST FORCING LOOKS ALIGNED FROM CAROLINE COUNTY ESE THROUGH THE VA ERN SHORE DURING THIS PERIOD...AND HAVE BUMPED POPS UP TO LIKELY IN MUCH OF EN VA N OF I-64. COLD AIR ARRIVAL IS ABOUT 3 HRS SLOWER THAN PREV MODELS...SO SNOW LOOKS TO BE DELAYED UNTIL AFTER 21Z IN THE FAR NW AND DORCHESTER MD...AND AFTER ABOUT 23Z/6 PM FROM METRO RICHMOND ON SE...AND AFTER 7 OR 8 PM VA BEACH TO COASTAL NC. LOOKS LIKE A CLASSIC CASE WHERE STRONG DYNAMICS WILL FIGHT W/ DRY LOW LEVELS. GFS IS THE MOST AGGRESSIVE AND A LITTLE FARTHER SOUTH THAN THE NAM/ECMWF W/ FORCING AND QPF AFTER 00Z (THAT WOULD MAINLY BE SNOW). HAVE BUMPED POPS UP TO HIGH CHANCE OVER MUCH OF THE CWA...BUT WILL CONFINE LIKELY POPS FOR SNOW TO CLIMO FAVORED NRN NECK AND VA ERN SHORE...MAINLY FROM 23Z- 03Z/SUN. W/ STRONG LIFT...COULD SEE A QUICK 1" OF SNOW IN THESE AREAS..BUT SFC TEMPS WILL HAVE BEEN RATHER WARM SO ROADS WILL SEE MINIMAL IMPACTS. ELSEWHERE WILL GO W/ 30-50% CHC SNOW SHOWERS...MAINLY IN THE EARLY EVENING (AS THICKNESSES DROP...SNOW WILL BE MAIN PTYPE ALL THE WAY TO THE NC COAST). WILL MENTION POSSIBILITY OF LIGHT SNOW ACCUMS IN HWO FOR NOW FOR ALL ZONES. TRENDS WILL NEED TO BE WATCHED CLOSELY BY LATER SHIFTS...IF THE SLIGHTLY MORE AMPLIFIED GFS VERIFIES...SNOW AMOUNTS AND CHANCES WILL NEED TO BE INCREASED...ALTHOUGH EVEN A WORST CASE SCENARIO WOULD ONLY BE LOCALLY 1-2" (AN ADVISORY). OTHER ISSUE LATE SAT AFTN THROUGH SUNDAY WILL BE WINDS. DURING THE AFTERNOON. THIS DEPTH OF INSTABILITY WOULD ALLOW SUSTAINED WINDS OF 20 TO 25 MPH TO BE FAIRLY UNIFORM ACROSS THE REGION. GUSTS SHOULD EASILY REACH 30 TO 35 MPH...POTENTIALLY REACHING 40 TO 45 MPH FOR A BRIEF PERIOD DURING THE EVENING WHEN THE PRESSURE GRADIENT TIGHTENS FURTHER AND COLD AIR ADVECTION MOVES INTO THE AREA. THE LOWER EASTERN SHORE SHOULD EXPERIENCE SLIGHTLY STRONGER SUSTAINED WINDS AND GUSTS DURING THE SAME TIMEFRAME AS THE COLD AIR ADVECTION ENHANCES NORTHWEST WINDS OVER CHESAPEAKE BAY AND NEARBY OCEAN WATERS. NORTHWEST FLOW PREVAILS ON SUNDAY AS THE MID ATLANTIC REGION REMAINS UNDER THE INFLUENCE OF THE UPPER LEVEL TROUGH. HIGH TEMPERATURES ON SUNDAY SHOULD RUN ABOUT 10-15 DEGREES BELOW NORMAL IN THIS COLDER WEATHER PATTERN...MID 30S ERN SHORE TO AROUND 40 SRN VA/NE NC. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... NEXT WEEK WILL FEATURE A STRONG UPPER LEVEL FLOW ACROSS THE CONUS WITH A SPLIT FLOW. NO ORGANIZED SYSTEMS ARE EXPECTED TO IMPACT THE AREA THROUGH THURSDAY. THERE IS UNCERTAINTY IN THE TIMING OF ANY SHORT WAVES THAT MAY AFFECT THE MID ATLANTIC STATES. A WEAK SOUTHERN STREAM SYSTEM COULD BRING SOME LIGHT RAIN TO THE REGION TUESDAY. AT THIS TIME...INCLUDED 30 PERCENT POPS OVER SE PORTIONS. ANOTHER SYSTEM MAY APPROACH THE AREA THURSDAY AND INCLUDED 30 PERCENT POPS OVER CENTRAL VIRGINIA. HIGH TEMPERATURES IN THE MID TO UPPER 40S WARM TO THE MID TO UPPER 50S WEDNESDAY AND THURSDAY. LOWS IN THE 20S MONDAY MORNING WARM TO THE 30S ACROSS THE AREA WEDNESDAY AND THURSDAY MORNINGS. && .AVIATION /09Z FRIDAY THROUGH TUESDAY/... HI PRES RIGHT OVR THE AREA ERLY THIS MORNG...WILL MOVE OFF THE CST THIS AFTN. MEANWHILE...A COLD FRNT WILL APPROACH FM THE NW AND WEAK LO PRES AREAS WILL DEVELOP OVR THE GULF CST AND SE STATES. EXPECT INCREASING HI AND MID LVL CLDS TO STREAM INTO THE REGION AHEAD OF THESE SYSTEMS THIS AFTN INTO THIS EVENG. SW WNDS WILL BE 5 TO 10 MPH OVR THE AREA. CIGS/VSBYS LWR QUICKLY TO MVFR THEN IFR LATER TNGT INTO SAT MORNG...AS LO PRES INTENSIFIES A BIT OVR THE CAROLINAS AND JUST OFF THE MID ATLC CST. THIS SYSTEM WILL BRING A PERIOD OF RAIN OR RAIN SHOWERS TO ALL TAF SITES FM LATER THIS EVENG INTO SAT MORNG. THE SFC LO WILL CONTINUE TO INTENSIFY DURING SAT AS IT MOVES NE AWAY FM THE REGION. CIGS/VSBYS SHUD IMPROVE TO VFR/MVFR CONDITIONS ALL TAF SITES BY LATE SAT MORNG OR ERLY SAT AFTN...AS NNW WNDS START TO USHER SOME DRIER AIR IN. HOWEVER...A STRONG COLD FRONT WILL DROP ACRS THE REGION LATE SAT AFTN THRU SAT NGT WITH GUSTY NNW WINDS 15 TO 25 KNOTS AND HIGHER GUSTS. ANY RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS SAT EVENG AND CONTINUE THRU SAT NGT...ESPLY OVR ERN HALF OF THE AREA AS THE COLD AIR MOVES IN WITH A VIGOROUS UPR LVL SYSTEM. GUSTY NW WINDS WILL CONTINUE INTO SUN AFTN...WITH VFR CONDITIONS EXPECTED SUN AND MON. THERE WILL BE A CHC FOR PCPN ON TUE. && .MARINE... GENERALLY CALM CONDITIONS TDY INTO TNGT WITH SSW WNDS 5 TO 15 KT...AS HI PRES MOVES OUT TO SEA AND A COLD FRNT APPROACHES FM THE NW WITH LO PRES DEVELOPING OVR THE SE STATES INTO THE CAROLINAS. BY 12Z SAT MORNG...LO PRES WILL BE JUST OFF THE MID ATLC CST WITH WNDS SHIFTING TO THE NNW OVR THE MARINE AREA. THE COMBINATION OF THAT LOW PRES AREA INTENSIFYING AS IT TRACKS NE AWAY FM THE REGION...AND ARCTIC HI PRES BLDNG IN FM THE WNW SAT AFTN THRU SUN MORNG...WILL PRODUCE STRNG/GUSTY NW WINDS ACRS THE MARINE AREA. HAVE GONE WITH A RAMP UP FM SCA HEADLINES TO GALE WRNG HEADLINES FOR ALL WTRS STARTING SAT AFTN. THE SCA WILL GO FM SAT AFTN THRU SAT EVENG...WITH GALE WRNG FM SAT EVENG THRU SUN MORNG (A LITTLE LONGER SUN MORNG OVR THE CSTL WTRS). WNDS/WAVES/SEAS WILL GRADUALLY DIMINISH/SUBSIDE SUN AFTN INTO MON MORNG...AS THE CNTR OF THE HI BLDS CLSR TO THE REGION. && .EQUIPMENT... THE NWS WAKEFIELD RADAR...KAKQ...WILL UNDERGO AN UPGRADE TO DUAL POLARIZATION TECHNOLOGY THROUGH THURSDAY FEBRUARY 16TH. RADAR DATA WILL BE UNAVAILABLE DURING THIS TIME. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY FROM 5 PM TO 10 PM EST SATURDAY FOR ANZ630>634-650-652-654-656-658. GALE WARNING FROM 10 PM SATURDAY TO 8 AM EST SUNDAY FOR ANZ630>634. GALE WARNING FROM 10 PM SATURDAY TO 11 AM EST SUNDAY FOR ANZ650-652-654-656-658. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB/BMD LONG TERM...LSA AVIATION...TMG MARINE...TMG EQUIPMENT...AKQ