000
AGXX40 KNHC 041745
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT FRI SEP 04 2009

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

GULF OF MEXICO...A WEAK FRONTAL TROUGH EXTENDING E TO W ALONG 
ROUGHLY 25N IS EXPECTED TO BEGIN TO DRIFT NW TONIGHT REACHING 
THE NW GULF WATERS LATE THIS WEEKEND. MODELS NOW SEEM TO HANG 
ONTO A WEAK TROUGH OVER THE NW PORTION THROUGH MON THEN MOVE IT 
IT AGAIN TUE INTO WED WITH AN E TO W RIDGE BUILDING TO ITS SE 
OVER THE CENTRAL WATERS. IN ANY EVENT...WINDS 5 TO 10 KT AND 
SEAS 1 TO 3 FT THROUGH PERIOD.

ATLC...A WEAK LOW LEVEL TROUGH WILL PERSIST OVER THE NW PORTION 
WITH LIGHT NLY WINDS W OF THE TROUGH. THE BIG UNCERTAINTY IS 
THE REMNANT LOW OF TS ERIKA SHOULD MOVE NW FROM THE CARIBBEAN 
INTO THE SE WATERS THIS WEEKEND. DEPENDING ON ITS TRACK AND HOW 
MUCH LAND IT ENCOUNTERS...IE THROUGH THE MONA PASSAGE OR ACROSS 
ALL OF HISPANIOLA...IT COULD BE A 25-30 KT LOW IN THE SE BAHAMAS 
OR A WEAK TROUGH. EXPECT THAT IN EITHER CASE THERE WILL BE TIGHT 
ENOUGH GRADIENT OVER THE NE SEMICIRCLE OF A LOW...OR A LARGE 
AREA E OF A TROUGH....TO MAINTAIN 20 TO 25 KT WINDS.
  
TROPICAL ATLC AND CARIBBEAN...AS REMNANTS OF ERIKA MOVE 
NORTHWESTERLY...THE GRADIENT ALONG COAST OF COLOMBIA WILL RELAX 
WITH WINDS BECOMING SE 15-20 KT OVER THE E CARIBBEAN THROUGH 
LATE SUN THEN TRADES RESUME THROUGH MID WEEK. FURTHER E...WEAK 
LOW PRES ALONG A TROPICAL WAVE AT 14N35W HAS BEEN MOVING W AT 11 
KT SINCE YESTERDAY....BUT SHOULD MOVE LITTLE FASTER REACHING 
ALONG 55W TUE NIGHT...MODELS DO NOT SEEM TO FAVOR DEVELOPMENT 
BUT LIKELY A NE TO SE WIND SHIFT. WAY FURTHER E...ANOTHER WAVE 
NEAR 22W IS CURRENTLY MOVING W AT 7 DEG PER DAY.  THIS MOTION 
SHOULD SLOW A LITTLE...WITH THE WAVE E OF 55W WED MORNING.   

WARNINGS
ATLC...
.NONE.

CARIBBEAN...
.NONE.

GULF OF MEXICO...
.NONE

$$
FORECASTER NELSON