Issued by NWS
000 AGNT40 KWNM 230144 MIMATN MARINE WEATHER DISCUSSION NWS OCEAN PREDICTION CENTER WASHINGTON DC 844 PM EST SUN 22 NOV 2009 .FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT .WEATHER FOR NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N. LARGE HIGH PRES CONTS TO BUILD SE ACROSS THE WATERS THIS EVENING. GRADIENT BTWN HIGH AND WEAK LOW PRES ABOUT 180 NM W NW OF BERMUDA IS PRODUCING NE WINDS 20 TO 25 KT...EXCEPT FAR NW WATERS 15 TO 20 KT. SEAS ARE 6 TO 10 FT S OF 40N...HIGHEST ABOUT 150 NM OFF THE NC AND SC COAST. NEW MODELS WERE SIMILAR TO THEIR 12Z RUNS. WILL ONLY MAKE MINOR CHANGES IN THE FCST UPDATE. FROM THE PRVS DSCN... 1357-1538Z HIGH RES ASCAT PASSES SHOW SOLID 15-20 KT OVR OUTER NT1 WTRS WHERE THERE IS DATA AND ALSO SML AREA OF DATA SHOWING 15 TO 25 KT NR DELMARVA COAST. THIS IS IN LN WITH WHAT BUOYS SUCH AS 44005...44008...44018...44025 AND 44009 HAVE BEEN RPTG WI PAST 2 HRS. SOME 25 KT RETRIEVALS SHOW UP NR EDG OF PASS WELL E OF CAPE FEAR. 12Z GFS INITIALIZED THESE WINDS WELL. FIRST PRD CONDS IN CURRENT FCST ARE IN LN WITH OBS. OTRW OVER THE SHORT TERM MODELS IN DECENT AGREEMENT THRU ABOUT 36HRS THAT UPPER HGTS WILL BUILD OVER NRN NEW ENGL/CANADIAN MARITIMES SUPPORTING A ZONALLY ORIENTED SFC RIDGE ACROSS THOSE AREAS...RESULTING IN TIGHTENING PRES GRADIENT OVER NEW ENGL/NRN MID ATLC WATERS THRU TONIGHT. THEN REGARDING THE CSTL REDVLPMT OF THE GLF STATES CLOSED LOW...THE UPR LOW WKNS AS IT APCHS MID ATLC CST MON THEN SHARPENS OFFSHORE AS UPR RDG BLDS BHND IT AHD OF NEXT CLOSED LOW LIFTINGOUT OF THE PLAINS. BY TUE MRNG GFS/CMC GGEM...UK AND EC 12Z RUNS SHOW NEUTRAL OR SLGTLY NEG TILT SHRTWV OFF MID ATLC CST/SRN NEW ENGLAND SPRTG MOVMT OF CSTL LOW NE TWD GEORGES BANK. CMC GGEM RMNS CONSISTENT WHILE 12Z GFS HAS BEEN MORE STABLE LAST FEW RUNS AND IS CLOSE TO CMC PSN/INTSTY ALTHO A COUPLE OF MB WEAKER TUE. IN SPITE OF THIS GFS BL WNDS SHOW GALES DVLPG N OF CNTR LATE MON STARTING NE NT2 WTRS...BALT CNYN TO HAGUE LN AND SPRDG NWD MON NIGHT. WITH LACK OF COLD AIR CONDS RMN RELATIVELY STABLE AND PREFER GFS 10M WNDS SPRTG MRGL GALES. UKMET/NAM DVLP ANOTHER LOW N OF BERMUDA TUE WHICH MAY AFFECT LOW TO NW AND ARE NOT SPRTD BY OTHER MDLS. EC DOES DVLP 10M WNDS 30 KT N OF CNTR MON NIGHT AND TUE AND BLENDING WITH GFS WOULD SPRT LOW TO MOD CONFDC FOR GALES HIGHEST FAR NE NT2 AND GEORGES BANK AREA. WILL LEAVE OTHER AREAS...GLF OF MAINE AND S OF NEW ENGL...AT LOW CONFDC. ALL MDLS THEN MOV LOW LOW NE WITH EXCEPTION OF OUTLIER UKMET AFFECTED BY SRN LOW E OF BERMUDA...GIVING WAY TO WK RIDGING WED. BY THU...MODELS ALL BRING STRONG CLOSED UPPER LOW THRU GREAT LAKES...SUPPORTING COLD FRONT APPROACHING COAST LATE WED AND OFFSHORE THU. MDL CONSENSUS SPRTS DVLPG SRN CSTL LOW ON OLD FNT OFF CAROLINAS THU AND DPNG AS IT MOVS N ENTRAINS COLD AIR ASCD WITH APCHG UPR LOW FRI. PLAN TO USE BLEND OF 12Z GFS/EC WHILE DISCONTING CMC GGEM WHICH LOOKS TOO PROGRESSIVE WHILE UKMET LOOKS TOO QUICK AND MOVG LOW INLAND. GFS/EC SPRTD BY 06Z GEFS/NAEFS AND 00Z ECMWF ENSEMBLE MEANS FOR LATE THU-FRI TAKING DPNG LOW N TO MAINE CST LATE FRI. PLAN TO LIMIT GALES FOR NOW TO FAR NE NT2 WTRS AND ERN NT1 ZONES FOR FRI...MRGL GALES WITH LOW TO MOD CONFDC. IN SPITE OF STG CAA S OF LOW GFS BL WNDS ONLY SHOW UP TO 30 KT BUT IF MDLS TREND DEEPER SOME OF THOSE AREA MAY NEED TO BE HEADLINED LATER. SEAS...WNA WW3 IS RUNNING WI A FOOT OF OBSVD CONDS EXCEPT IN SRN NT2 WTRS IN NE FLOW TO 25 KT WHERE CONDS ARE MORE UNSTABLE...RPTD SEAS ARE UP TO 3 FT ABV MDL. WILL MAKE SIMILAR ADJUSTMENTS SHORT-TERM. WILL TONE DOWN THE 15-17 FT MAX SIG WV HGTS NE NT2 AND SE NT1 WTRS WW3 IS SHOWING MON NIGHT INTO TUE BY 1-2 FT AND 1 FT GLF OF MAINE WHERE GALES FCST. .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 TUE...LOW CONFDC. GALE FRI...LOW TO MOD CONFDC. .GEORGES BANK...GALE LATE MON INTO TUE...LOW TO MOD CONFDC. GALE FRI...LOW CONFDC. .S OF NEW ENGLAND...GALE MON NGT INTO TUE...LOW COFDC. .NT2 MID ATLC WATERS... .HUDSON TO BALT CNYN...NONE. .BALT CNYN TO HAGUE LINE...GALE LATE MON INTO TUE...LOW TO MOD CONFDC. GALE FRI...LOW TO MOD CONFDC. .BALT CNYN TO HATTERAS CNYN...NONE. .HATTERAS CNYN TO CAPE FEAR...NONE. .CAPE FEAR TO 31N...NONE. .FORECASTER PROSISE/BAMCROFT. OCEAN FORECAST BRANCH.
