000
AGXX40 KNHC 101544
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1200 PM EDT WED JUN 10 2009

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

ATLC...
THE UPPER LEVEL PATTERN IS MARKED BY A POSITIVELY TILTED TROUGH 
THAT LIES FROM 31N40W TO 07N53W. ANOTHER TROUGH LIES ALONG 
75W...WITH A LOW AMPLITUDE UPPER RIDGE CENTERED ALONG 65W. THE 
00Z/06Z MODELS GENERALLY AGREE ON ALLOWING SOME OF THE SHORTWAVE 
ENERGY WITHIN THE WESTERN TROUGH TO SPILL OVER THE 
RIDGE...AMPLIFYING THE TROUGH OVER THE CENTRAL ATLANTIC WHILE 
THE REMAINDER OF THE WESTERN TROUGH MIGRATES FARTHER W OVER FL 
AS THE ANTICIPATED TROUGH/LOW IN THE WESTERN CARIBBEAN LIFTS 
NORTHWARD. CONFIDENCE IS VERY LOW IN THE DETAILS. THE GFS AND 
CMC MODELS SEEM TO HAVE THE BEST HANDLE ON THE SHORTWAVE DETAILS 
OVER THE SW N ATLC AT THE MOMENT...BUT NEITHER OF THEIR 
SOLUTIONS ARE PREFERRED IN THE WESTERN CARIBBEAN AT THE TAIL END 
OF THE TROUGH. THE GFS APPEARS TO HAVE GRID-SCALE FEEDBACK 
ISSUES WITH THE WAVE IT LIFTS NORTH ALONG 72W OVERNIGHT TONIGHT. 
ADJUSTED ITS SOLUTION TOWARD A WEAKER TROUGH HERE...BUT USED ITS 
FORECAST UNTIL THE WEEKEND WHEN THE CARIBBEAN SYSTEM COMES INTO 
THE MIX. FOR THE WEEKEND...RELIED ON THE ECMWF AS RECOMMENDED BY 
HPC MEDIUM RANGE FOR THE COLD FRONT PASSING OFF THE E COAST N OF 
THE AREA AND THE DOWNSTREAM RIDGE OVER SW N ATLC WATERS.

THE TROPICAL WAVE ALONG 44W WILL CONTINUE W NEAR 15 KT INTO THE 
CARIBBEAN BY SUN. AT THE SAME TIME...THE SUBTROPICAL HIGH 
CENTERED NEAR 29N30W OVER THE EASTERN ATLC WILL SHIFT 
WEST-SOUTHWEST TO 27N53W BY SAT MORNING WITHOUT AN APPRECIABLE 
CHANGE IN STRENGTH. EXPECT THE WIND FIELD ASSOCIATED WITH THE 
NORTHERN EDGE OF THE WAVE TO EXPAND AS IT MOVES WEST AS A RESULT 
OF THE INCREASED PRES GRADIENT.

CARIBBEAN...
THE PROBLEM OF THE DAY LIES WITH THE FORECAST FOR THE EVOLUTION 
OF THE TROUGHING OVER THE WESTERN CARIBBEAN. THE GFS DEVELOPS A 
WELL-DEFINED SURFACE LOW BY THU MORNING AND LIFTS IT MORE 
RAPIDLY TO THE N THAN THE OTHER MODELS. THE CONSENSUS IS FOR A 
WEAKER SOLUTION AND A MORE NW THAN N TRACK THROUGH THE WESTERN 
CARIBBEAN. THE FORECAST WAS ADJUSTED TOWARD THIS CONSENSUS. 
CONFIDENCE IS EXTREMELY LOW.

GULF OF MEXICO...
THE FORECAST PERIOD IS VERY QUIET IN THE GULF OF MEXICO...WITH 
LITTLE CONVECTION EXPECTED THROUGH SAT. WINDS TO 20 KT ARE ONLY 
EXPECTED WITH THE RETURN FLOW IN THE WESTERN GULF. MORE 
UNCERTAINTY COMES INTO PLAY BY THE WEEKEND AS THE SYSTEM IN THE 
SW CARIBBEAN MAY APPROACH S WATERS...BUT UNCERTAINTY IS VERY 
HIGH FOR THE TIMING AND STRENGTH OF THIS SYSTEM. THE FORECAST 
FOLLOWS THE MORE SOUTHWESTERLY CONSENSUS FOR THE WESTERN 
CARIBBEAN SYSTEM AS OPPOSED TO THE STRONGER AND MORE EASTERLY 
TRACK OF THE GFS.

WARNINGS

ATLC...
.NONE.

CARIBBEAN...
.NONE.

GULF OF MEXICO...
.NONE.

FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.