000
AGNT40 KWNM 260720
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
320 AM EDT TUE JUL 26 2016

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

CRNT LGTNG DENSITY PROD INDC TSTMS ACRS NE NT2 NEAR N WALL OF
GULF STREAM IN W TO SW FLOW...AND ALSO ALONG A LOW PRES TROF NEAR
THE MID ATLC COAST. THE 00Z GFS/ECMWF INDC A MDT AMT OF
INSTABILITY OVR NT2 WITH THE PREDOMINANTLY SW FLOW INJECTING
HEAT/MOISTURE INTO THE PBL. ALSO...THE MDLS INDC A PAIR OF SFC
BNDRYS OVER THE AREA IN THE SHORT RANGE...TO ACT AS A FOCUS FOR
CONVECTION...OVR NRN NT2. THE PREV FCST CARRIED SCTRD TSTMS AND
SHOWERS IN NT2...SO PLANNING ON MAINTAINING MENTION IN THE NEXT
PKG.

OTRW...THE 00Z MDLS ALL INDC THE AFOREMENTIONED SFC TROF WL MOVE
INTO THE AREA EARLY TDA...FLWD BY A FRNTL BNDRY CRNTLY JUST SE OF
THE GREAT LAKES REGION...LATER TDA INTO TNGT. 0235Z ASCAT WIND
RETRIEVALS AND CRNT SFC RPRTS INDC WINDS CRNTLY UP TO 20 KT IN
THE SW FLOW AHD OF THE SFC TROF...AND 0235Z RSCAT WINDS EXTEND A
LTL FURTHER E OVER THE GULF STREAM AND INDC 25 KT. THE 00Z GFS
WNDS ARE INIT OK WHEN COMPARED WITH THE CRNT DATA...AND INDC THAT
THE WINDS WL NOT INCRS ANY FURTHER THAN 25 KT AHEAD OF THE TWO
BNDRYS. THE 00Z GFS AGREES FAIRLY WELL WITH THE 00Z ECMWF/UKMET/NAM/GEM
MDL RUNS WITH THE TMG OF THE BNDRY...BUT IS SLGTLY STGR THAN THE
ECMWF/UKMET...AND A LTL WKR THAN THE 00Z NAM/GEM. ATTM THE GFS
SEEMS TO BE ABT THE BEST CMPRMS SOLN IN THE SHORT RANGE...AND
SEEMS MOST RSNBL...SO PLANNING ON FAVORING IT INTO THU NGT WHICH
KEEPS FCST IN LINE WITH PREV ONE.

THE BIGGEST FCST PROBLEM IS IN THE EXTENDED PD...AS THE 00Z GFS
IS A FAST OUTLIER WITH THE NEXT SYS ON FRI INTO SAT. THE GFS HAD
SLOWED SLIGHTLY TWD THE OVERALL MDL CONSNESUS WITH THE 18Z
RUN...BUT HAS TRENDED FASTER AND AWAY FM IT WITH THE 00Z RUN. IN
ADDITION...THE 00Z UKMET/GEM HAVE TRENDED TWD THE CONSISTENT ECMWF
SOLN...WHICH IS ALSO SUPPORTED BY THE 00Z GEFS/ECWMF/NAEFS MEAN
SOLNS. AS A RESULT...PLANNING ON FAVORING THE 00Z ECMWF SOLN FROM
FRI 06Z ONWARD...THO WL BOOST WINDS INVOF THE GULF STREAM WHERE
THE ECMWF WINDS SEEMS A BIT LOW.

.SEAS...BOTH THE 00Z WAVEWATCH III AND ECMWF WAM MDLS HV BOTH
INITIALIZED THE CURRENT W ATLC WAVE HEIGHTS VERY WELL...WITH WV
HTS CRNTLY 6 FT OR LESS IN THE W ATLC. THE MDLS ARE IN GOOD
AGREEMENT INTO FRI...SO PLANNING ON USING 00Z WW3 UNTIL THEN. WL
THEN SWITCH TO 00Z ECMWF WAVE SOLN BY 06Z FRI...TO REFLECT
PREFERRED WX MDL TRENDS. ALSO...WW3 BUILDS SEAS FASTER THAN THE
ECMWF WAM...AS A RESULT OF STGR WINDS WITH THE FASTER LOW...SO
PREFER TO STAY AWAY FM IT ATTM.

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

.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
NONE.

.NT2 MID ATLC WATERS...
NONE.

$$

.FORECASTER KELLS. OCEAN PREDICTION CENTER.