Forecast Discussion for Central Virginia
000
FXUS61 KAKQ 230246
AFDAKQ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
946 PM EST WED FEB 22 2012
.SYNOPSIS...
A WEAK TROUGH OF LOW PRESSURE SWINGS ACROSS THE AREA TONIGHT. A
STRONG COLD FRONT WILL CROSS THE AREA FRIDAY. HIGH PRESSURE BUILDS
IN FROM THE WEST DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A RATHER POTENT SHORTWAVE TROUGH IS MOVING ACROSS EASTERN TN AND
KY THIS EVENING. A LINE OF LOW-TOPPED SHOWERS AND THUNDERSTORMS
HAVE FORMED ALONG AND AHEAD OF THE TROUGH AXIS...WITH AN ADJACENT
LINE EXTENDING ENE ACROSS SW AND W-CENTRAL VA ASSOCIATED WITH A
ZONE OF LOW-LEVEL CONFLUENCE. THIS ACTIVITY SHOULD CONTINUE ON AN
ENE TRACK LATE THIS EVENING THROUGH THE EARLY OVERNIGHT HOURS.
EARLIER CONVECTION ACROSS FL HAS INHIBITED NORTHWARD TRANSPORT OF
RICHER GULF MOISTURE...SO INSTABILITY WILL BE RATHER LIMITED EAST
OF THE APPALACHIANS. NEVERTHELESS...THE COMBINATION 0-6KM BULK
SHEAR MAGNITUDES AROUND 60KT AND A PASSING MID-LEVEL THETA-E RIDGE
COULD RESULT IN SOME EMBEDDED THUNDER. LATEST RADAR/SATELLITE TRENDS
INDICATE THE HIGHEST POPS WILL BE ACROSS THE NORTHERN PORTION OF
THE CWA LATE THIS EVENING WITH THE PRECIPITATION POTENTIAL
INCREASING ACROSS THE CENTRAL PORTION OF THE AREA AFTER MIDNIGHT
AS THE TROUGH AXIS SWINGS THROUGH. SHOWER ACTIVITY IS EXPECTED TO
DECREASE QUICKLY AFTER 09Z AS THE TROUGH MOVES OFF THE COAST. QPF
AMOUNTS SHOULD RANGE BETWEEN 0.1 AND 0.25IN...BUT A NARROW ZONE OF
0.25 TO PERHAPS 0.5IN IS POSSIBLE NORTH OF AN FVX-RIC LINE. LOW
TEMPERATURES TONIGHT SHOULD RANGE FROM THE MID 40S W...TO LOW 50S
SE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
VRY MILD/WRM TEMPS (FOR THIS TIME OF YEAR) EXPECTED FOR THU AND
FRI...WITH A RETURN TO MORE SEASONAL TEMPS ON SAT. DECENT WSW SFC
WNDS (10 TO 15 MPH AND GUSTY) SET UP OVR THE AREA ON THU...AND
UNDR A PRTLY SNY...TEMPS WILL WRM INTO THE UPR 60S TO LWR 70S
(WOULD NOT RULE OUT SOME MID 70S...ESPLY ACRS SRN VA/INTR NE NC).
STRONG COLD FRNT APPROACHES/CROSSES THE MTNS THU NGT...THEN
PUSHES ACRS THE AREA AND TO JUST OFF CST BY 00Z SAT. STILL
LEANING TWD FASTER COMBINATION OF GFS/NAM/SREF WITH REGARD TO
TIMING/MOVEMENT OF COLD FRNT AND ASSOCIATED POPS. REMAINING
UNSEASONABLY WRM AHEAD OF AND EVEN BEHIND THE FRNT THU NGT THRU
FRI. LATEST MDL GUIDANCE CONTINUES TO SHOW LIMITED MOIST ASSOC
WITH THE FRNTL PASSAGE...WITH POTENTIAL EXCEPTION EXTRM SRN/SE VA
AND NE NC. WILL CONTINUE TO HAVE HIEST (CHC) POPS IN THOSE PLACES.
ALSO...GUSTY WSW WNDS TO 25-35 MPH EXPECTED AHEAD OF AND BEHIND
THE FRNT. QUICK DRYING ANTICIPATED POST FRNTL FRI AFTN/EVENG...AS
SFC WNDS BECOME MORE WNW...THO COOLING WILL LAG BY A FEW HRS. AS A
RESULT...STILL EXPECT HIGHS ON FRI IN THE UPR 60S TO LWR 70S.
COLDER/DRIER AIRMASS SETS UP OVR THE REGION FOR FRI NGT THRU
SAT...AS HI PRES GRADUALLY BLDS TWD THE MID ATLC FM THE CNTRL
U.S. MSTLY CLR FRI NGT WITH LOWS RANGING FM THE LWR 30S TO LWR
40S. PRTLY TO MSTLY SNY ON SAT WITH HIGHS IN THE UPR 40S TO MID
50S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
BREEZY WINDS DURING THE DAY ON SATURDAY ARE EXPECTED TO DIMINISH
LATE SATURDAY NIGHT AS A SURFACE HIGH MOVES OVERHEAD BY SUNDAY
MORNING. THIS WILL SET THE STAGE FOR OPTIMAL RADIATIONAL COOLING
WITH TEMPS FALLING TOWARD NORMAL VALUES IN THE LOW TO MID 30S (MID
20S-LOW30S EASTERN PIEDMONT). MOSTLY CLEAR BUT STABLE CONDITIONS ARE
ANTICIPATED SUNDAY AS RIDGING REMAINS ANCHORED OVER THE AREA. AN
INCREASING SUN ANGLE AND A SLIGHTLY LONGER PERIOD OF DAYTIME HEATING
COULD BE ENOUGH TO BOOST TEMPERATURES ABOVE READINGS EXPERIENCED ON
SATURDAY...DESPITE LIMITED MIXING CONDITIONS.
LONG RANGE MODEL SOLUTIONS CONTINUE TO DIVERGE THROUGH EARLY NEXT
WEEK. HOWEVER...THE ECMWF MODEL IS SHOWING SOME SIGNS OF COMING INTO
AGREEMENT WITH THE GFS MODEL. DESPITE THIS TREND...THERE ARE STILL
ENOUGH DIFFERENCES BETWEEN EXTENDED MODELS TO MAKE LITTLE TO NO
CHANGES TO THE FORECAST DURING THIS TIMEFRAME.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
SOUTHERLY WINDS WILL STAY BREEZY THROUGH THIS EVENING AT ALL TAF
SITES AS WESTERLY FLOW ALOFT PREVAILS AND A LOW PRESSURE SYSTEM
APPROACHES THE AREA TONIGHT. MID LEVEL CEILINGS HAVE SPREAD OVER THE
REGION AS AN AREA OF LIGHT TO MODERATE SHOWERS HAS MOVED FROM THE
WESTERN PORTION OF VIRGINIA AND SPREAD OVER THE PIEDMONT AND
CENTRL VIRIGINA. CEILINGS WILL CONTINUE TO LOWER THROUGH TONIGHT
AS LIGHT RAIN SHOWERS PUSH ACROSS THE REGION LATE. VISIBILITIES
SHOULD NOT DROP BELOW 5SM UNLESS A HEAVIER SHOWER MOVES OVERHEAD.
BRIEF RIDGING ON THURSDAY WILL IMPROVE CONDITIONS DURING THE DAY
AND THEN A STRONGER COLD FRONT WILL TRACK ACROSS THE REGION LATE
THURSDAY NIGHT THROUGH FRIDAY. EXPECT STRONG AND GUSTY WINDS AHEAD
OF AND BEHIND THE FRONTAL PASSAGE. LIGHT RAIN WITH THE FRONT WILL
LIKELY PRODUCE LOWERED CEILINGS...AND POTENTIALLY RESTRICT
VISIBILITIES OVER SE VA/NE NC UNDER HEAVIER SHOWERS. BREEZY
NORTHWEST WINDS ARE EXPECTED TO PERSIST THROUGH SATURDAY AS SKIES
CLEAR. WINDS SHOULD THEN DIMINISH SATURDAY NIGHT AS STRONG HIGH
PRESSURE BUILDS OVER THE AREA THROUGH SUNDAY NIGHT. SOUTHWEST
WINDS DEVELOP BY MONDAY AS HIGH PRESSURE PUSHES OUT TO SEA.
&&
.MARINE...
PREVAILING WIND DIRECTION WILL BE FROM THE SW THROUGH FRIDAY. A WEAK
DISTURBANCE PASSES OVER THE WATERS TONIGHT AND WILL INCREASE WINDS
TO 15 TO 20 KT. SOME GUSTS UP TO 30 KT ARE POSSIBLE OVER COASTAL
WATERS NORTH OF NEW POINT COMFORT TONIGHT. ALTHOUGH WINDS WILL BE
MARGINAL IN THESE AREAS...SEAS ARE EXPECTED TO REACH 5 FT. ALSO
TONIGHT...SCA CONDITIONS FOR WINDS WILL DEVELOP OVER CHESAPEAKE
BAY AND CURRITUCK SOUND. HAVE KEPT SCA HEADLINES IN PLACE FOR
THESE AREAS BEGINNING AT 10 PM TONIGHT. WINDS/SEAS QUICKLY
DIMINISH BELOW SCA THRESHOLDS THURSDAY MORNING.
THURSDAY NIGHT THROUGH THE WEEKEND...A STRONG COLD FRONT IS FORECAST
TO MOVE ACROSS THE MID ATLANTIC REGION FRIDAY...QUICKLY
DETERIORATING CONDITIONS OVER AREA WATERS DUE TO STRONG WINDS AND
RAIN. BEHIND THE FRONT...ANOTHER ROUND OF COOLER WEATHER WILL MOVE
IN FOR THE REMAINDER OF THE WEEKEND. SOLID SCA CONDITIONS APPEAR
LIKELY THURSDAY NIGHT THROUGH AT LEAST SUNDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THURSDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THURSDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...TMG
NEAR TERM...TMG/AJZ
SHORT TERM...TMG
LONG TERM...BMD
AVIATION...JEF
MARINE...JEF
NWS AKQ Office Area Forecast Discussion
