

275 

AGNT40 KWNM 281404

MIMATN



MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN 

NWS OCEAN PREDICTION CENTER WASHINGTON DC

1005 AM EDT THU 28 JUL 2016 



.FORECAST DISCUSSION: MAJOR FEATURES/WINDS/SEAS/SIGNIFICANT 

.WEATHER FOR THE NORTH ATLANTIC OCEAN W OF 50W FROM 30N TO 50N. 



THE OVERNIGHT MODELS CAME INTO MUCH BETTER AGREEMENT WITH THE 

MORE NRN SURFACE LOW TRACK ACROSS THE NT1 WATERS LATE FRI INTO 

SAT. THE 06Z GFS IS NOW EVEN SLIGHTLY N OF THE 00Z ECMWF/UKMET 

AND A FEW MB DEEPER. BY LATE SUN AND MON MODELS DIVERGE WITH 

ANOTHER DEVELOPING SURFACE LOW. ALTHOUGH TIMING DIFFERENCES ARE 

MUCH LESS THAN WAS THE CASE WITH THE FRI/SAT SYSTEM...WHEN 

COMPARED TO THE 00Z ECMWF/UKMET THE GFS IS FURTHER S WITH LOW 

TRACK. WILL NOT BE MAKING SIGNIFICANT ADJUSTMENTS TO PREVIOUS 

OPC WIND/WAVE HEIGHT GRIDS IN THIS MORNINGS UPDATES. 



THE SEVERAL 4 FT BUOY REPORTS OVER THE COASTAL AND INNER 

OFFSHORE WATERS S OF CAPE LOOKOUT ARE ABOUT 1 FT HIGHER THAN 

LATEST WAVEWATCH III OR ECMWF WAM GUIDANCE. ELSEWHERE ACROSS THE 

W ATLC THIS GUIDANCE IS WELL INITIALIZED WITH WAVE HEIGHTS THIS 

MORNING.



----------------------------------------------------------------

...PREVIOUS DISCUSSION...



THE 00Z SFC ANALYSIS INDICATED A STATIONARY FRONT EXTENDING FROM 

NEAR CAPE MAY E ACROSS THE FAR NRN NT2 WATERS...WITH A WEAK 

TROUGH ALONG THE NEW ENGLAND COAST. ASCAT PASSES FROM LATE WED 

EVENING INDICATED THE STRONGEST WINDS IN THE 10 TO 15 KT RANGE 

OVER THE SRN HALF OF THE NT2 WATERS...WITH WINDS 10 KT OR LESS 

OVER THE REMAINDER OF AREA. SATELLITE IMAGERY AND LIGHTNING DATA 

INDICATE SOME STRIKES OVER CENTRAL NT2 ZONES WITH WEAKENING 

CLUSTER OF TSTMS MOVING OFF N CAROLINA COAST. 



THE 00Z MODELS ARE IN DECENT AGREEMENT DURING THE IMMEDIATE 

SHORT TERM PERIOD THROUGH THIS EVENING...WITH DIFFERENCES 

PERSISTING FOR THE REMAINDER OF THE FCST PERIOD. THE MAIN FCST 

ISSUE WILL BE LOW PRES WHICH IS FCST BY ALL THE MODELS TO MOVE 

OFF THE NEW JERSEY COAST LATE FRI MORNING OR EARLY 

AFTERNOON...THEN TRACK NE ACROSS THE NEW ENGLAND WATERS FRI 

NIGHT WITH ASSOCIATED COLD FRONT PUSING SE. THE 00Z UKMET HAS 

TRENDED A BIT FASTER COMPARED TO THE 12Z RUN FROM 

YESTERDAY...MAINLY AFTER 00Z SAT AND A BIT FURTHER N. THE 00Z 

GFS SEEMS TO BE A DECENT COMPROMISE BETWEEN THE UKMET AND THE 

12Z ECMWF FROM WED...AND IS ALSO CLOSE TO THE 00Z GEM. WITH THIS 

IN MIND...PLAN TO POPULATE USING THE GFS 10M WINDS FROM TODAY 

THROUGH 00Z MON. LOOKING AHEAD TO 00Z MON AND BEYOND...ANOTHER 

LOW IS FCST TO MOVE ACROSS THE NT1 WATERS WITH THE 00Z UKMET 

BEING THE FURTHEST N WITH THE TRACK AND THE GFS WEAKER AND 

FURTHER S. IN THIS CASE...THE 12Z ECMWF APPEARS TO BE A GOOD 

COMPROMISE BETWEEN THE WEAKER FURTHER S GFS AND THE UKMET WHICH 

IS MORE N...SO FOR NOW WILL POPULATE USING THE ECMWF WINDS 

BEGINNING 00Z MON THROUGH THE END OF PERIOD. WILL MAKE FINAL 

DECISION AFTER 00Z ECMWF ARRIVES. 



.SEAS...THE 03Z SEA STATE ANALYSIS INDICATED THAT THE OBSERVED 

SEAS CONTINUE TO MATCH UP WELL WITH THE MWW3. SIMILAR TO THE 

WIND GRIDS...WILL USE THE MWW3 THROUGH 00Z MON...THEN WILL 

TRANSITION TO ECMWF WAM FOR THE REMAINDER OF THE PERIOD. 



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



.WARNINGS...PRELIMINARY. 



.NT1 NEW ENGLAND WATERS... 

     NONE. 



.NT2 MID ATLC WATERS... 

     NONE. 



$$ 



.FORECASTER CLARK/KOSIER. OCEAN PREDICTION CENTER.

