NHC Marine Weather Discussion

000

AGXX40 KNHC 281854

MIMATS

MARINE WEATHER DISCUSSION

NWS NATIONAL HURRICANE CENTER MIAMI FL

254 PM EDT THU MAY 28 2015

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN

SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND

64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS.

...GULF OF MEXICO...

MODEL PREFERENCE: GLOBAL MODEL CONSENSUS

A WEAKENING SURFACE RIDGE PREVAILS OVER THE GULF COAST

STATES...EXTENDING FROM SHIFTING ATLC RIDGE NOW CENTERED NEAR

38N48W. THIS YIELDING MODERATE E TO SE FLOW ACROSS MOST OF BASIN

EXCEPT 15-20 KT THROUGH STRAITS OF FL. SEAS GENERALLY 3-5 FT

EXCEPT 2-3 FT NE PART. YUCATAN TROUGH HAS NEARLY DISSIPATED ALONG

95W WITH SEAS STILL 4-5 FT INVOF 42055. THE RIDGE WILL PERSIST OVER

THE GULF COAST STATES THROUGH FRI THEN RETREAT EASTWARD SATURDAY.

THIS WILL BRING A DECREASE IN OVERALL WINDS AND SEAS ACROSS MUCH

OF THE GULF WATERS THIS WEEKEND INTO EARLY NEXT WEEK. THE NEXT

SIGNIFICANT SHORTWAVE WILL MOVE ACROSS TEXAS AND EXTREME NW WATERS

FRI TO BRING ANOTHER ROUND OF VERY ACTIVE WEATHER THERE...SHIFTING

TO CENTRAL PORTIONS SAT. A THERMALLY INDUCED SURFACE TROUGH WILL

DEVELOP EACH EVENING OVER THE YUCATAN. THE TROUGH WILL DRIFT

WESTWARD DURING THE OVERNIGHT HOURS BEFORE DISSIPATING OVER THE SW

GULF EACH MORNING.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN

55W AND 64W...

MODEL PREFERENCE: GLOBAL MODEL CONSENSUS

BROAD TROUGH N OF THE AREA ACROSS W CENTRAL ATLC HAS WEAKENED THE

PRESSURE GRADIENT OVER THE CARIBBEAN..AND TYPICAL JET FROM A-B-C'S

TO COLOMBIA NOW DOWN TO AROUND 20 KT AND 8 FT. MODERATE TO FRESH

ENE FLOW PREVAILS ACROSS NW PORTIONS FROM LEE OF CUBA TO YUCATAN

WHILE LIGHT TRADES WERE RECENTLY DEPICTED IN GULF OF HONDURAS BY

15Z ASCAT PASS. SE FLOW HAS INCREASED VERY SLIGHTLY ACROSS NE

CARIB AS SE WINDS ARE BEGINNING TO OPEN UP AND AROUND E SIDE OF

BROAD ATLC TROF. TROPICAL WAVE ACROSS S HALF OF TROPICAL N ATLC

WATERS AND APPROACHING WINDWARDS ATTM WITH TRADES INCREASING TO

15-20 NEAR AND BEHIND WAVE.

THE BROAD TROUGH WILL CONTINUE TO DRIFT WESTWARD AND N OF THE

CARIBBEAN THROUGH THE WEEKEND BUT WILL HAVE SHIFTED FAR ENOUGH W

BY SAT TO ALLOW STRONG CENTRAL ATLC RIDGE TO BUILD S INTO TROPICAL

ATLC TO INCREASE TRADES ACROSS TROPICAL N ATLC WATERS TO 20 KT BY

SAT...AS WELL AS E TO ESE TRADES AROUND 20 KT BEHIND TROPICAL WAVE

AS IT MOVES SLOWLY ACROSS ERN CARIB THROUGH THE WEEKEND. THIS WILL

BRING AN INCREASE IN SEAS ACROSS TROPICAL N ATLC AND FAR ERN

CARIB SUNDAY AND MONDAY AS A LONG FETCH OF FRESH WINDS SOUTH OF

ATLANTIC HIGH DEVELOPS. SEAS WILL BUILD TO 8 FT OVER THE SOUTHERN

PORTION OF THE TROPICAL N ATLC WATERS TONIGHT INTO FRIDAY AND PEAK

AROUND 9 FT SAT.

REORGANIZING DEEP LAYERED CUT OFF LOW ACROSS ATLC WILL AID IN

PULLING WAVE RELATED MOISTURE N AND NW ACROSS ERN CARIB THIS

WEEKEND TO DESTABILIZE THE REGION AND PRODUCE AREAS OF ACTIVE

WEATHER THERE. MODEL BEGIN TO DIVERGE SUN ACROSS W CENTRAL CARIB

AS GFS AMPLIFIES INVERTED TROFFING ALONG 80W AND ALLOW MOISTURE TO

ADVECT MUCH FARTHER NW AND BEYOND CARIBBEAN NEXT WEEK...WHILE

ECMWF REMAINS FLATTER. PREFER ECMWF SOLUTION DURING THAT PERIOD.

...SW N ATLANTIC INCLUDING THE BAHAMAS...

MODEL PREFERENCE: GLOBAL MODEL CONSENSUS

A BROAD INVERTED TROUGH DOMINATES THE WATERS E OF 72W. LATEST

DATA DEPICTS A WEAKENING LOW NEAR 25.5N67.5W WHERE SCAT WINDS

SHOWED 20-25 KT ACROSS N SEMICIRCLE...WHILE A SECOND WEAK LOW HAS

DEVELOPED UNDERNEATH THE UPPER LOW NEAR 25N61W. STRONG WINDS

PREVAILING ACROSS NRN PERIPHERY OF BROAD TROUGH HAVE SHIFTED TO N

AND NE OF NEW SECOND LOW...AS PREDICTED BY GUIDANCE...AS ATLC HIGH

IS SHIFTING EWD AND TO THE N OF THIS TROUGH. SEAS 8 TO 12 FT

ACROSS THE BROAD ELONGATED FETCH ACROSS THE TOP OF TROUGH...WHILE

SEAS TO 9 FT EXTEND SW FROM THERE TO 71W PER RECENT BUOY OBS.

THE BROAD TROUGH WILL TAKE ON MORE OF A NE-SW ORIENTATION OVER

THE NEXT COUPLE OF DAYS WHILE IT SLOWLY DAMPENS OUT THROUGH

MONDAY...BUT WITH LESSER PERTURBATIONS MOVING THROUGH THIS FLOW AS

A REFLECTION OF REORGANIZING UPPER LOW. THIS PATTERN WILL

MAINTAIN A WEAK PRESSURE GRADIENT OVER THE FORECAST AREA THROUGH

MOST OF NEXT WEEK BEFORE MODELS SHOW POTENTIAL FOR CYCLOGENESIS

ACROSS S FL AND NW BAHAMAS LATE NEXT WEEK. GFS IS ABOUT 36-48 HOUR

FASTER THAN ECMWF WITH THIS DEVELOPMENT AND AM HESITANT TO GO WITH

GFS ATTM.

$$

.WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE

COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE:

.GULF OF MEXICO...

NONE.

.CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN

55W AND 64W...

NONE.

.SW N ATLANTIC INCLUDING THE BAHAMAS...

NONE.

$$

*FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT:

WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF

NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE

NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT:

WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP

FOR ADDITIONAL INFORMATION PLEASE VISIT:

HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE

$$

.FORECASTER STRIPLING. NATIONAL HURRICANE CENTER.

http://www.nhc.noaa.gov/text/MIAMIMATS.shtml