000
AGXX40 KNHC 040537
MIMATS
MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
140 AM EDT FRI JULY 4 2008
MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND
SOUTHWEST NORTH ATLC S OF 31N W OF 55W.
GULF OF MEXICO...
A TYPICAL SUMMERTIME PATTERN PREVAILS WITH THE ATLC SUBTROPICAL
RIDGE EXTENDING ACROSS THE NORTHERN GULF...WITH AN AXIS BETWEEN
28-29N. A WEAK PRESSURE PATTERN ACROSS THE NE HALF OF THE GULF
IS CAUSING LIGHT TO MODERATE WINDS...WITH MOST LOCATIONS N OF
25N E OF 90W REPORTING 10 KT OR LESS. ONLY OVER THE NW GULF ARE
SE TO S WINDS IN THE 10 TO 15 KT RANGE. SEAS ARE LIKEWISE FAIRLY
LOW...WITH BUOY...SHIP REPORTS...AND CMAN STATIONS INDICATING
SEAS OF 2 FT OR LESS OVER THE NE CORNER. OTHERWISE...SEAS OF 2
TO 4 FT SEAS ARE COMMON IN A STRIPE COMING OUT OF THE STRAITS OF
FLORIDA THROUGH THE S CENTRAL GULF AND ALSO OVER THE NW...WHERE
SE WINDS ARE PILING UP THE WATER OFF THE S TX COAST. BUOY 42020
OFFSHORE CRP HAS THE HIGHEST SEAS EARLY THIS MORNING WITH A
REPORT OF 5 FT.
MEANWHILE...THE DIFFERENCE BETWEEN HIGH PRES TO THE N AND A 1006
MB LOW PRES ARE S OF MEXICO IN THE EPAC IS CREATING MODERATE TO
FRESH E TO SE WINDS OVER THE SW HALF OF THE GULF. IN FACT
...SINCE YESTERDAY EVENING...BUOY 42055 NEAR 22N94W HAS BEEN
REPORTING NEAR CONSTANT 20 KT WINDS AND SEAS OF 5 FT IN SE WIND
WAVES. IN ADDITION...A 0018 UTC QUIKSCAT PASS SHOWS A LARGE
AREA OF E TO SE 15 TO 20 KT WINDS S OF 23N BETWEEN 89W AND 94W
AND S OF 27N BETWEEN 94W AND THE COAST. IN GENERAL...SEAS
AVERAGE BETWEEN 3 TO 5 FT OVER THIS AREA...THOUGH PEAK SEAS OF 6
TO 7 FT ARE POSSIBLE.
FROM NOW UNTIL EARLY NEXT WEEK...GLOBAL MODELS SHOW LITTLE
CHANGE TO THE ABOVE PATTERN...WITH LIGHT/MODERATE E TO SE WINDS
OVER THE NE HALF OF THE GULF AND MODERATE TO FRESH TRADES OVER
THE SW. GIVEN THE DURATION OF MODERATE TO FRESH WINDS OVER THE
SW GULF...THE NOAA WAVEWATCH III MODEL IS INDICATING SEAS
POSSIBLY BUILDING TO 8 FT S OF 25N W OF 92W BY SUN...WITH SOME
FURTHER INCREASE POSSIBLE LATE SUN INTO MON. OTHERWISE...A WEAK
MID- TO UPPER-LEVEL DISTURBANCE CENTERED NEAR THE S TX COAST
SHOULD HANG AROUND THROUGH AT LEAST SAT...LIKELY ENHANCING THE
POTENTIAL FOR SCATTERED CONVECTION OVER THE WRN THIRD OF THE
GULF...ESP NEAR THE TX AND NE MEXICAN COASTS. OUTSIDE OF THESE
AREAS...EXPECT FAVORABLE MARINE CONDITIONS OVER A LARGE PART OF
THE GULF.
CARIBBEAN...
AFTER A WEEK OR TWO OF TURBULENT MARINE CONDITIONS LASTING INTO
EARLY THIS WEEK...CONDITIONS HAVE EASED CONSIDERABLY THE LAST
FEW DAYS. LATEST SFC ANALYSIS SHOWS A FAIRLY TYPICAL SUMMERTIME
PATTERN WITH A NEAR NORMAL ATLC SUBTROPICAL RIDGING EXTENDING
INTO THE CARIBBEAN BASIN. THE ONLY OTHER FEATURE OF IMPORTANCE
IS A TROPICAL WAVE S OF 17N ALONG 70/71W MOVING W AT 10-15 KT.
OTHER THAN A WEAK CYCLONIC CURVATURE TO THE LOW-LEVEL WINDS OVER
THE EASTERN AND CENTRAL CARIBBEAN AND SCATTERED
CONVECTION...THIS FEATURE APPEARS INSIGNIFICANT TO MARINE
WEATHER.
AN EVENING QUIKSCAT PASS FROM YESTERDAY DID SHOW A BROAD AREA OF
MODERATE TO OCCASIONALLY FRESH TRADES...ROUGH FROM 11N TO 17N
BETWEEN 68W AND ALMOST 80W. REPORTS FOR THE TWO NOAA BUOYS
ACROSS THE AREA AS WELL AS ISOLATED SHIP REPORTS INDICATE THAT
SEAS ARE RANGING FROM 5 TO 8 FT IN E WIND WAVES. ELSEWHERE...
LIGHT TO MODERATE TRADES SEEM TO BE THE RULE OVER THE SW AND NW
CARIBBEAN SEA...THOUGH QUIKSCAT DID SHOW ENHANCED ELY FLOW IN
THE GULF OF HONDURAS WITH WIND SPEEDS UP TO 25 KT. SEAS RANGE
FROM 3 TO 5 FT IN THE NW TO 5 TO 8 FT IN THE SW AND THE GULF OF
HONDURAS IN NE TO E SWELL.
LITTLE CHANGE TO THE ABOVE PATTERN IS ANTICIPATED FOR THE NEXT
DAY OR TWO. HOWEVER...GLOBAL MODELS ARE SUGGESTING THAT THE
LOW-LEVEL SUBTROPICAL RIDGE SHOULD RE-STRENGTHEN SUN INTO
MON...COINCIDING WITH THE PASSAGE OF THE NEXT TROPICAL WAVE
CURRENTLY ALONG 51W/52W. TRADES OF 20 TO 25 KT SHOULD ACCOMPANY
THE WAVE OVER THE EAST CENTRAL AND CENTRAL CARIBBEAN LATE SUN
INTO MON...WITH SEAS BRIEFLY BUILDING UP TO 6 TO 10 FT. BY TUE
...WINDS AND SEAS SHOULD INCREASE OVER MOST OF THE WRN CARIBBEAN
S OF ABOUT 18/19N...WITH NE TO E SWELL ARRIVING ACROSS THE AREA.
SW ATLC/TRPCL N ATLC...
AN ENHANCED ATLC SUBTROPICAL RIDGE EXTENDS INTO THE SW ATLC THIS
MORNING...WITH AN AXIS RUNNING WSW FROM 30N76W TO 29N80W. A
VARIETY OF DATA SOURCES ARE INDICATING SE TO S WINDS AROUND 10
KT EXCEPT S TO SW WINDS OF 10 TO 15 KT VERY NEAR THE FL NE
COAST. S OF THE RIDGE AXIS...ELY TRADES ARE ENHANCED IN A
STRIPE S OF ABOUT 23N. SEAS GENERALLY RANGE FROM 3 TO 5 FT TO
THE N EXCEPT NEAR THE NE FL COAST WHERE THE OFFSHORE FLOW HAS
ALLOWED FOR SLIGHTLY LOWER SEAS OF 1 TO 2 FT. S OF 24N SEAS OF 5
TO 7 FT PREVAIL E OF THE BAHAMAS WITH 2 TO 4 FT THE RULE E OF
THE BAHAMAS EXCEPT NEAR THE FL SE COAST WHERE REPORTS OF 1 TO 2
FT ARE COMMON.
LITTLE CHANGE TO THE ABOVE PATTERN IS EXPECTED OVER THE NEXT
SEVERAL DAYS. HOWEVER...THE NORTHERN END OF A TROPICAL WAVE NOW
ALONG 512/52W SHOULD CAUSE SOME INCREASE TO THE TRADES AND BRING
MORE UNSETTLED CONDITIONS S OF 22-23N LATER SUN INTO MON.
OUTSIDE OF THIS FEATURE...EXPECT FAIRLY BENIGN MARINE CONDITIONS
THROUGH THE PERIOD.
OVER THE TRCPL N ATLC...OBSERVATIONS SHOW NE TO E WINDS OF 10 TO
15 KT ACROSS THE AREA WITH SEAS OF 4 TO 6 FT. THE TROPICAL WAVE
CURRENTLY ALONG 51W/52W SHOW PASS THROUGH THE REGION RATHER
UNEVENTFULLY TODAY AND SAT...WITH NO SIGNIFICANT CHANGE TO THE
CURRENT MARINE CONDITIONS EXPECTED.
BEGINNING LATE MON INTO TUE...TROPICAL STORM BERTHA IS FORECAST
TO LIE JUST NE OF THE FORECAST AREA WITH MAX WINDS OF 60 KT
...WITH THE CURRENT FORECAST TRACK NOTABLY E OF THE LATEST GFS
RUN. ALONG THE FORECAST TRACK...INCREASING NE WIND OF 20 KT
SHOULD ARRIVE OVER THE NRN WATERS AROUND THIS TIME....WITH LONG
PERIOD NE SWELL PROPAGATING AWAY FROM THE STORM ARRIVING OVER
THE NE WATERS INITIALLY MON AND THEN SPREADING S AND W BY TUE.
ENSEMBLE WAVEWATCH GUIDANCE DOES SHOW A FAIRLY HIGH CHANCE OF
GREATER THAN 12 FT SEAS OVER THE NE WATERS...THOUGH THIS WILL OF
COURSE BE DEPENDENT ON THE EXACT TRACK OF THE STORM. OF
NOTE...SINCE THE STORM IS EXPECTED TO PASS NE OF THE AREA...THE
MAIN EFFECTS WILL LIKELY BE SIGNIFICANT LONG PERIOD NE SWELL.
PLEASE REFER TO THE LATEST TPC DISCUSSION ON BERTHA FOR FURTHER
INFORMATION.
ATLANTIC...
.NONE.
CARIBBEAN...
.NONE.
GULF OF MEXICO...
.NONE.
.FORECASTER KIMBERLAIN. TROPICAL PREDICTION CENTER.
