Marine Interpretation Message
Issued by NWS

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000
AGNT40 KWNM 301252
MIMATN

MARINE WEATHER DISCUSSION FOR N ATLANTIC OCEAN
NWS OCEAN PREDICTION CENTER WASHINGTON DC
852 AM EDT MON MAY 30 2016

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

LATEST RADAR INDICATES THAT T.D. BONNIE REMAINS JUST INLAND OF THE
S CAROLINA COAST. HIGHEST WINDS FOUND WERE AT BUOY 41025 WITH
150/21 G 25 KT WHICH WERE LKLY AIDED BY THE SYSTEM/S ASCD
CONVECTIVE BANDS. HIGHEST ASCD SEAS ARE IN THE 6-8 FT RANGE
(CONFIRMED BY AN EARLIER 0807Z JASON ALTIMETER PASS) WHICH ARE
SLIGHTLY HIGHER THAN FCST BY BOTH THE 06Z WAVEWATCH III AND 00Z
ECMWF AT THE MOMENT.

THE 06Z NAM/GFS CONT THE TRENDS DISCUSSED EARLIER AND PRESENT NO
MAJOR FCST PROBLEMS. IN RGRDS TO THE FCST TRACK OF T.D. BONNIE...
VS ITS PREV 00Z RUN...THE 06Z GFS...WHICH IS SPRTD BY ITS 06Z GEFS
MEAN...HAS TRENDED SLOWER WHICH BRINGS IT MR IN LINE WITH THE 00Z
ECMWF AND TO A LESSER DEGREE THE 00Z UKMET. THEREFORE WULD NOT BE
SURPRISED TO SEE NHC ADJUST THEIR PREV FCST TRACK SLOWER IN THE
NEXT ADVSRY. THE PREVLY POPULATED GRIDS USED THE 00Z GFS BL
WINDS...TIME SHIFTED SLOWER. THEREFORE SINCE THE 06Z GFS IS
SLOWER WL CONT TO USE THESE WINDS WITH JUST SM ADDITIONAL MINOR
EDITS LKLY DICTATED BY THE NEXT NHC ADVSRY FOR BONNIE. SO
ANTICIPATE MAKING ONLY MINOR CHNGS IN THE NEXT OFSHR FCST PACKAGE.



-----------------------------------------------------------------
PREVIOUS DISCUSSION...

GOES IR IMGRY INDC TROPICAL DEPRESSION BONNIE JUST INLAND OVER
SOUTH CAROLINA...AND A WARM FRONT OVER THE GULF OF MAINE. BONNIE
CONT TO HAVE THE GREATEST IMPACT ON WEATHER OVER THE OFSHR WATERS
ATTM...AS THE WV IMGRY INDC AN UPPER RIDGE OVER THE NRN PORTION OF
NT2. THE 03Z ASCAT PASS LARGELY MISSED THE HIGHEST WINDS AROUND
BONNIE...THO IT RETRIEVED 20 KT IN THE WRLY FLOW ON THE SW SIDE OF
THE LOW CENTER. CRNT SFC RPRTS INDC ABT 15 KT JUST OFF THE SC
COAST...THO THE RSCAT DATA FM 0030 UTC RSCAT PASS STILL HAD ABT 25
TO 30 KT...THO MANY WERE RAIN-FLAGGED. THE 00Z GFS INDC 20 TO 25
KT JUST OFF THE SC COAST...AND THE 00Z ECMWF/UKMET SOLNS INDC ONLY
ABT 20 KT. FROM THIS...IT SEEMS THAT BONNIE HAS WEAKENED SOME...AS
IT HAS MOVED INLAND...THO 25 KT TO START DOES NOT SEEM
UNREASONABLE FOR THE NEXT FCST. NHC HAS BEEN MAINTAINING 25 KT
FOR A MAJORITY OF THE FCST AS THE SYS MOVES SLOWLY NE...SO WOULD
NOT EXPECT MUCH TO BE DIFFERENT IN THE NEXT ADVISORY WHEN
COMPARING THE TRACK AND INTNSTY IN THE 00Z GLOBAL MODELS TO PREV
RUNS. THE 00Z HAS SPED UP SLIGHTLY WITH BONNIE IN THE THU TO FRI
TIMEFRAME...AND THE 00Z ECMWF/UKMET/GEM HAVE ALL TRENDED MUCH
SLOWER FROM THEIR PREV RESPECTIVE RUNS. ATTM PREFERRING A
COMPRMISE SOLN BETWEEN THE 00Z GFS AND ECWMF SOLNS...WHICH IS
CLOSE TO THE PREV NHC FORECAST TRACK.

OTRW...THE 00Z MODELS AGREE FAIRLY WELL THAT THE CDFNT ASSOC WITH
A SHORTWAVE TROF CRTNLY MOVING THROUGH THE ERN GREAT LAKES REGION
WILLMOVE OVER NT1 TONIGHT INTO TUE. THE 00Z GFS 30M WINDS INDC 25
KT IN THE SW FLOW AHEAD OF THE FRONT...WHICH SEEMS A TAD HIGH
GIVEN THE STABLE ENVIRONMENT OVER THE COLD SHELF WATERS. THE TEMPS
BEHIND THE FRONT DO NOT SEEM THAT IMPRESSIVE...SO 20 KT SEEMS
RSNBL. THE 00Z MODELS THEN INDC A SECOND FRONT WL MOVE INTO NRN
NT2 TUE NGT INTO WED...AS HIGH PRES BUILDS OVER NT1 FROM THE N.
THERE IS SOME UNCERTAINTY AS TO WHETHER OR NOT A SECOND LOW WL
FORM ALONG THE FRONT AHEAD OF BONNIE...AND THE 00Z GFS/GEM INDC A
STRONGER SOLN THAN THE 00Z UKMET/ECMWF. ATTM 25 KT SEEMS A LTL
OVERDONE FOR NT1 ON FRI...SO PLANNING ON CAPPING WINDS AT 20 KT IN
NT1. FOR THE FCST...WL BE GENLY FLWG THE 00Z GFS...BUT WL BE
MAKING ADJUSTMENTS BASED ON NHC`S OFFICIAL TRACK FOR BONNIE.

SEAS...BUOY DATA OFF THE SC COAST INDC THE 00Z MULTIGRID WAVEWATCH
III AND 00Z ECWMF WAM MDLS HAVE BOTH INITIALIZED WITHIN 1 FT OF
THE DATA...AND LIKEWISE FOR THE REMAINDER OF THE WRN ATLC. THE
MODELS AGREE FAIRLY WELL THRUT THE FCST...AND DIFFER MAINLY WITH
THE TRACK OF BONNIE. FOR THE FCST...PLANNING ON FLWG THE 00Z NWW3
MODEL...BUT WL ADJUST BASED ON NHC`S FORECAST FOR BONNIE.

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


.WARNINGS...PRELIMINARY.

.NT1 NEW ENGLAND WATERS...
     NONE.

.NT2 MID ATLC WATERS...
     NONE.

$$

.FORECASTER VUKITS/KELLS. OCEAN PREDICTION CENTER.



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