FXUS61 KAKQ 270948
AFDAKQ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
448 AM EST FRI NOV 27 2009
.SYNOPSIS...
LOW PRESSURE INTENSIFIES OFF THE NEW ENGLAND COAST...PRODUCING
GUSTY NORTHWEST WINDS TODAY. HIGH PRESSURE WILL THEN BUILD INTO
THE AREA TONIGHT AND SATURDAY...BEFORE MOVING OFF THE COAST ON
SUNDAY. A COLD FRONT MOVES ACROSS THE AREA ON MONDAY. HIGH
PRESSURE REBUILDS INTO THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRONG VORTICITY MAX CONTINUES TO ROTATE THROUGH THE AREA AND WILL
EXIT OFF THE COAST BY 12Z. IN ITS WAKE...WILL CONTINUE TO SEE
SHOWERS LIFT FROM SE VA INTO THE DELMARVA THROUGH ABOUT 14Z. AFTER
THAT THE NW WILL BEGIN TO TAKE OVER AND DOMINATE THE CONDITIONS.
THIS WILL ALLOW FOR SOME CLEARING TO MOVE INTO THE AREA. ONE
ADDITIONAL SHORTWAVE DROPPING SE ON THE BACK SIDE OF THE CLOSED
LOW WILL SLIDE ACROSS THE AREA THIS AFTERNOON...PRODUCING MAINLY
JUST SOME CLOUDS...BUT SOME ISOLATED SHOWERS OR SPRINKLES COULD
DEVELOP ACROSS THE NORTHERN NECK AND THE DELMARVA WITH THIS WAVE.
BEHIND THIS WAVE...SFC HIGH PRESSURE BUILDS INTO AND WITH MUCH
DRIER AND COLD AIR...SHOULD SEE CLEARING AND DRY CONDITIONS DEVELOP.
HIGH TEMPERATURES TODAY WILL BE MUCH COOLER THAN YESTERDAY. WITH
THE COLD ADVECTION AND 850 MB TEMPERATURES DOWN AROUND -4C...WILL
STRUGGLE TO SEE HIGHS IN MID 50S. SO HAVE LEANED TOWARD THE COOLER
MET. TONIGHT SHOULD BE THE COLDEST NIGHT OF THE PATTERN. BUT WITH
THE WINDS STILL UP...IT MAY NOT BE GREAT RADIATION CONDITIONS...SO
HAVE LEANED TOWARD THE SLIGHTLY WARMER MAV VALUES.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
VERY QUIET PERIOD WEATHER WISE AS THE UPPER TROUGH IS IN PLACE ON
SATURDAY AND THEN EXITS TO THE EAST WITH THE UPPER RIDGE BUILDING
INTO THE SATURDAY NIGHT AND SUNDAY. WITH VERY DRY AIR
AROUND...SHOULD SEE MAINLY CLEAR AND DRY CONDITIONS. WITH THE
RISING HEIGHTS...WILL BEGIN TO SEE TEMPERATURES MODERATE ON
SATURDAY AND THEN JUMP ON SUNDAY AS THE WARM ADVECTION KICKS THE
850 MB TEMPERATURES ALL THE WAY UP TO AROUND 10C...WHICH SHOULD
ALLOW TEMPERATURES TO CLIMB INTO THE UPPER 60S TO THE LOWER 70S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
FRONTAL BOUNDARY DRAPED ACROSS THE GRT LKS INTO THE SRN PLAINS WILL
SLOWLY TREK TWRD THE RGN ON MON AS A LOW PRES SYSTEM RIDES ALONG IT.
HIGH CLOUDS WILL INCREASE SUN NIGHT BEFORE FRONTAL SYSTEM AND ASSCD
LOW PRES SYSTEM MOVES OVER THE RGN MON AFTN/EVE. LOOK FOR SHRA
ACTIVITY TO CONTINUE INTO ERLY TUE BEFORE HIGH PRES STARTS TO BUILD
BACK INTO THE RGN. STRONG UPR LVL SYSTEM DVLPS OVER THE SRN CALIF ON
SAT AND DIGS FURTHER OVER NRN MEXICO/SRN TX INTO MON. SYSTEM PUSHES
INTO THE GULF COAST TUE/WED AND QUICKLY MOVES TWRDS THE RGN ON THU
AS SRN STREAM FLOW STARTS TO FLATTEN. GFS ONCE AGAIN TRIES TO DVLP A
COASTAL SYSTEM...BUT OTHER GUIDANCE HINTING AT MORE OF A SUPRESSED
AND WEAKER SYSTEM FURTHER SOUTH (WHICH WOULD BE MORE SUPPORTIVE
OF A FLATTER FLOW). FOR NOW WILL GO WITH BULK OF GUIDANCE.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
MID LEVEL DISTURBANCE PUSHIGN ACROSS THE AREA HAS MADE FOR
WIDESPREAD IFR/LIFR CONDITIONS ACROSS TERMINALS. CONDITIONS FINALLY
BEGINNING TO IMPROVE OVER INLAND ZONES (PHF-RIC) AND SHOULD OCCUR
OVER THE NEXT FEW HOURS AT ORF/ECG. AS DISTURBANCE SLOWLY TRANSLATES
OFFSHORE...WL LKLY SEE MVFR/IFR CIGS AND SOME SHRAS PERSISTING INTO
EARLY MORNING HOURS AT KSBY.
OTW...CLEARING CONDITIONS TO VFR LOOK TO OCCUR BY MID MORNING AT ALL
SITES. WITH CONVECTIVE WNDS FINALLY DIMINISHING...MAIN OPERATIONAL
CONCERN WL BE W/GUSTY NON-CONVECTIVE WINDS TODAY AS THE COLD STRONG
PRESSURE GRADIENT BETWEEN NEW ENGLAND CSTL LOW AND AN APPROACHING
SFC RIDGE TO THE S WL ALLOW FOR BREEZY TO WINDY CONDS LTR THIS
MORNING THROUGH THE TAF PERIOD W/GUSTS TO 20-30KT POSSIBLE DURING
THIS PERIOD.
CLEARING SKIES AND DRIER AIRMASS SHOULD ALLOW FOR VFR CONDITIONS OVER
THE WEEKEND INTO ERY NEXT WEEK...WITH THE NEXT CHC FOR SIG PCPN LKLY
COMING BY LTR MON/TUE.
&&
.MARINE...
LITTLE HAS CHANGED WRT FORECAST RATIONALE FOR THE NEXT 24 TO 36 HRS.
COASTAL LOW CURRENTLY BOMBING OUT OFF THE NEW ENGLAND COAST...AS
SFC HIGH PRESSURE BUILDS IN FROM THE SOUTHEASTERN CONUS. COLD FRONT
NOW OFF THE MID-ATL COAST...AND CAA IS NOW IN PROGRESS OVER STILL
RELATIVELY WARM WATERS. HV GONE AHEAD AND STARTED GALE WARNINGS
WITH THIS MORNINGS CWF ISSUANCE. NON-CONVECTIVE GALE GUSTS LOOK TO
HOLD OFF INTO THE LTR MORNING INTO THE AFTN AS SECONDARY MIDLVL
SHORTWAVE LOOKS TO PINWHEEL THROUGH ON THE BACK EDGE OF DEPARTING
NEG TILTED UPR TROF. HOWEVER...WITH EXPECTED GALE WITHIN THE FIRST
PERIOD...WL GO AHEAD AND UPGRADE TO THE PREDOMINANT GALE HEADLINE.
BUFKIT DATA AND 00/06Z GFS/NAM/WRF-AKQ MODEL H92-85 WNDS FIELDS
ALL POINT TO SOLID HIGH END SCA CONDITIONS TODAY...WITH MORE THAN
AMPLE MOMENTUM XFER TO MIX DOWN GUSTS TO ~40 KT ACROSS THE MARINE
AREA TODAY INTO AT LEAST LTR TONIGHT...AND LIKELY LONGER (INTO SAT
AFTN) OVER NORTHERN COASTAL WATERS AS GRADIENT LOOKS TO BE SLOW TO
RELAX DURING THE DAY SATURDAY. ELSEWHERE...A SCA FOR SEAS WL
LIKELY BE NEEDED AFTER GALES COME DOWN TONIGHT OR ERY SATURDAY OVER
THE BAY/SOUTHERN COASTAL WATERS INTO LTR SAT AT LEAST. CONDITIONS
LOOK TO BECOME A BIT MORE BENIGN FOR SUNDAY INTO MONDAY AS FLOW
LOOKS TO TURN SSW AS HIGH PRESSURE OVER THE SOUTHEAST CONUS BUILDS
SOUTH OF THE REGION. ANOTHER FRONT APPROACHES FROM THE WEST BY LTR
MONDAY/TUESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...GALE WARNING UNTIL 5 AM EST SATURDAY FOR ANZ630>633-654-656-
658.
GALE WARNING UNTIL 6 PM EST SATURDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...ESS
NEAR TERM...ESS
SHORT TERM...ESS
LONG TERM...CCW
AVIATION...MAM
MARINE...MAM
