507
AGNT40 KWNM 271318
MIMATN
MARINE WEATHER DISCUSSION
NWS OCEAN PREDICTION CENTER WASHINGTON DC
810 AM EST FRI 27 NOV 2009
.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N.
THE MOST SIG ADJUSTMENTS FOR THE MORNING UPDATE WILL BE TO ADJUST
SEA HTS TO FIT THE RAPIDLY BUILDING SEAS MAINLY FROM SRN NT1 WTRS
S OVR NT2 WTRS...OR FROM NR CAPE COD SOUTHWARD. SEA HTS PER THE
12Z RA1 OPC SEA STATE ANALYSIS SHOW SEA HTS FROM 2 TO 8 FT ABV
THE 06 WW3 MDL GUID OVR THIS REGION. WE WILL ATTEMPT TO FIT THESE
SEA HTS WITH THE ONGOING FCST BEFORE SENDING THE FCST THIS
MORNING. ALSO PER THE LATEST OBS OVR THE REGION WHERE GUSTS ARE
NR STORM FORCE WE WILL GO AHEAD AND ADD STORM WNGS TO THE BALT TO
HAT CANY WTRS FOR THE REST OF TDA INTO EARLY TONITE WITH THE
STORM FORCE WINDS LKLY SPREADING NE WITH THE UPR LVL LOW TONITE
COVERING THE BALT CNYN TO HAGUE LINE AREA. OTW...NO MAJOR CHANGES
ARE ANTICIPATED FOR THE UPDATE. WE WILL CONT TO MENTION TSTMS IN
THE OFF WTRS ESPEC OVR NRN NT2 WTRS WHERE THE LATEST LGTNG DATA
SHOWS ACTIVITY OFF THE DELMARVA IS ASSOC WITH THE UPR LVL LOW OR
STRONG DISTURBANCE.
----------------------------------------------------------
PREV DISCUSSION...
LATEST SFC OBS CONTINUE TO SHOW GUSTS TO GALE FORCE OFF THE SC
COAST AND NR CAPE FEAR. EXPECT THIS TO CONTINUE INTO THE EARLY
MORNING HOURS...WITH THE STRONGER WINDS BEGINNING TO LIFT TO THE
NORTH LATER THIS MORNING AND INTO THIS AFTERNOON AS UPR TROF
BEGINS TO LIFT TO THE NE.
00Z GFS AND UKMET IN GOOD AGRMT WITH THE OVERALL WEATHER PATTERN
THRU DAY 5 AND IS IN DECENT AGRMT WITH THE 12Z/26 ECMWF.
MAIN FCST PROBLEM IS POSSIBILITY OF STORM FORCE WINDS ACROSS THE
NRN NT2 WATERS FOR TONIGHT INTO SAT IN THE STRONG CCA MOVING OFF
THE COAST. LATEST GFS HAS BACKED DOWN SLIGHTLY FROM ITS PREV
RUNS AND IS ONLY SHOWING MAX BL WINDS OF 45 KT ACROSS THE NRN
NT2 WATERS FRI NIGHT INTO SAT. HOWEVER...LOOKING AT 00Z GFS
MODEL SOUNDINGS...DOES SHOW POSSIBILITY OF MINIMAL STORM FORCE
WINDS MIXING DOWN TO THE SFC. 00Z UKMET SHOWING 35 TO 40 KT
WINDS...BUT IS USUALLY IS ABOUT 5 TO 10 KT UNDERDONE. WILL GO
AHEAD AND KEEP WINDS TO STORM IN THE GULF STREAM ACROSS THE NRN
NT2 WATERS FRI NIGHT AND SAT WHERE THE GREATEST INSTABILITY WILL
RESIDE. OTW...REMAINDER OF HEADLINES LOOK GOOD. MAY KEEP GALES
UP ACROSS THE WATERS E OF 68W INTO THE SUN PERIOD AS BOTH THE
GFS AND UKMET A BIT SLOWER MOVING THE GALES OUT OF THE OFFSHR
WATERS.
GFS STILL LOOKS A BIT TOO FAST WITH THE NEXT FRONT TO AFFECT THE
OFFSHR WATERS MON...BUT BY ONLY ABOUT 6 HRS. BOTH THE GFS AND
THE UKMET SHOW FRONT MOVING E OF THE OFFSHR WATERS BY 12Z TUE.
WILL HAVE WINDS SHIFTING TO THE NW ACROSS THE REGION AT THAT
TIME. AS FOR PREFRONTAL WINDS. BOTH THE GFS AND THE UKMET
CONTINUE TO SHOW GALE CONDITIONS DEVELOPING IN THE SWLY FLOW
AHEAD OF THE FRONT ACROSS THE NRN NT2 WATERS DURING THE DAY MON.
GFS ALSO DOES INDICATE THE POSSIBILITY OF GALES STRETCHING INTO
THE BALT TO HATTERAS WATERS MON AS WELL...AND THIS IS SUPPORTED
BY THE UKMET. SO WILL GO AHEAD AND INTRODUCE GALES INTO THE NE
PORTION OF THE BALT TO HATTERAS CANYON WATERS FOR MON...WHILE
KEEPING GALES IN THE BALT TO HAGUE LINE AREA. GALES SHUD SUBSIDE
BY 12Z TUE AS THE FRONT MOVES E OF THE AREA.
NEED TO WATCH NEXT SYSTEM BOTH GFS AND UKMET HAVE IN THE GULF
TUE THAT MAY AFFECT THE EAST COAST WED.
SEAS...WW3 LOOKS REASONABLE ACROSS THE CSTL/OFFSHR WATERS WHEN
COMPARED TO LATEST SFC OBS. WILL GENERALLY STAY CLOSE TO THE
MODEL FOR THIS PACAKGE...WITH THE EXCEPTION OF BUMPING SEAS A
BIT IN THE GULF STREAM SAT DUE TO THE STRONG CCA. DO NOT SEE ANY
SIG DIFFERENCES FROM PREV RUN.
WARNINGS/FORECAST CONFIDENCE
WARNINGS ARE PRELIMINARY AND ARE
SUBJECT TO CHANGE. ANY CHANGES WILL BE COORDINATED THROUGH AWIPS
12 PLANET CHAT OR BY TELEPHONE.
NT1 NEW ENGLAND WATERS
GULF OF MAINE...GALE INTO EARLY SUN
HI CONFDC.
GEORGES BANK...GALE INTO EARLY SUN
HI CONFDC.
S OF NEW ENGLAND...GALE INTO SAT NITE
HI CONFDC.
NT2 MID ATLC WATERS
HUDSON TO BALT CNYN...GALE INTO SAT NITE
HI CONFDC.
BALT CNYN TO HAGUE LINE...GALE INTO SUN...HI CONFDC
WITH
STORM IN AND NEAR THE GULF STREAM TONITE INTO SAT...MDT CONFDC.
GALE
MON...MDT CONFDC.
BALT CNYN TO HATTERAS CNYN...STORM TDA INTO EARLY TONITE
MDT
CONFDC...OTW...GALE THRU SAT...HI CONFDC. GALE MON...LOW TO MDT
CONFDC.
HATTERAS CNYN TO CAPE FEAR...GALE THRU TONITE
HI CONFDC.
CAPE FEAR TO 31N...GALE TDY
MDT TO HI CONFDC.
.FORECASTER MILLS/ACHORN. OCEAN FORECAST BRANCH.
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