000
AGNT40 KWNM 291845
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
245 PM EDT TUE 29 JUL 2014

.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT
.WEATHER FOR THE NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N.

15Z HI RES ASCAT-B OVERPASS RETURNED 20 TO 30 KT WINDS E OF COLD
FRONT EXTENDING FROM SRN GEORGES BANK TO NEAR 37N71W. OFF THE SE
COAST SFC LOW HAS DVLPD ALONG COLD FRONT OFF SC COAST AND 12Z
MDLS ARE IN GOOD AGREEMENT THAT AS LOW MOVES NE ALONG FRONT
LATER TDA INTO WED WILL SEE ENHANCEMENT IN S TO SW WINDS E OF
FRONT OVER E SEMICIRCLE OF LOW. THESE HIGHER WINDS WILL BE
LIMITED TO EXTREME OUTER OFFSHORE WATERS. 12Z GFS BNDRY LAYER
WINDS WHICH INDICATE WINDS UP TO 30 KT LOOK REASONABLE WHEN
COMPARED TO 15Z ASCAT PASS AND ARE ALSO SUPPORTED BY BOTH 12Z
UKMET AND 00Z ECMWF SFC WINDS. WILL CONTINUE TO FAVOR THESE
WINDS AHEAD OF FRONT OVER NEXT 48HRS. WEAK HIGH PRES RIDGE
MEANWHILE WILL BUILD TO NRN MID ATLC AND NEW ENGL COAST OVER
NEXT COUPLE DAYS. UPPER HGTS SHOULD BUILD SOMEWHAT ALONG NEW
ENGL AND MID ATLC COASTS AS INLAND UPPER LOW SYSTEM WEAKENS OVER
SERN ONTARIO AND SRN QUEBEC WITH OFFSHORE MID/UPPER LVL SW FLOW
ALSO WEAKENING. AT THE SFC MDLS AGREE THAT WEAKENING STNRY FRONT
WILL BEGIN TO DRIFT N AND NW AS WEAK WARM FRONT THU NGT THRU
SAT. MDL SOLUTIONS THEN DIVERGE SOMEWHAT LATE SAT AND SUN AS GFS
CONTINUES TO LIFT THE WEAK BOUNDARY TO COASTAL ME. THERE IS
REASONABLE AGREEMENT BETWEEN 12Z GFS AND 12Z ECMWF BUT 12Z UKMET
MAINTAINS STNRY FRONT ACROSS NEW ENGL WATERS THRU SUN NGT. AM
FAVORING A 50/50 12Z GFS/12Z ECMWF BLEND LATE SAT THRU SUN
NGT...WITH WINDS LESS THAN 20 KT.

12Z MULTIGRID WAVEWATCH III SEEMS TO HAVE A DECENT HANDLE ON SIG
WV HGTS OVER W ATLC THIS AFTERNOON. WITHIN HIGHEST SW WINDS E OF
COLD/STNRY FRONT OVER NEXT 48HRS 12Z MWW3 IS ABOUT 3 FT OR SO
HIGHER THAN 12Z ECMWF WAVE MDL. BASED ON 10Z JASON-2 ALTIMETER
PASS OVER THESE SW WINDS WHICH INDICATED SIG WV HGTS A COUPLE FT
HIGHER THAN MWW3...AM FAVORING HIGHER 12Z MWW3 AND OVER WARMER
GULF STREAM WATERS WILL ADD A FT OR TWO TO THIS GUIDANCE OVER
THE NEXT 36HRS.

.EXTRATROPICAL STORM SURGE GUIDANCE...N/A.

.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
NONE.

.NT2 MID ATLC WATERS...
NONE.

$$

.FORECASTER CLARK. OCEAN PREDICTION CENTER.