000
AXNT20 KNHC 100532
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT FRI APR 10 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0515 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 5N8W 2N14W CROSSING THE EQUATOR NEAR 
18W AND EXTENDING TO 3S27W 4S35W INTO NE BRAZIL NEAR 4S39W. 
SCATTERED MODERATE CONVECTION IS FROM 1N-3N BETWEEN 1W-2W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 240 NM 
OF AXIS BETWEEN 10W-20W.

...DISCUSSION...

THE GULF OF MEXICO...
SFC HIGH PRES HAS MOVED E OF THE AREA INTO THE W ATLC. THIS HAS 
ALLOWED SLY RETURN FLOW TO DEVELOP ACROSS THE ENTIRE GULF 
ADVECTING A MILDER AND MORE MOIST AIRMASS THAN WHAT WAS IN PLACE 
EARLIER THIS WEEK. LATEST SFC OBS AND QSCAT DATA SHOW THE 
STRONGEST FLOW...20-25 KT...OVER THE W WATERS IN RESPONSE TO LOW 
PRES OVER THE PLAINS AND ASSOCIATED TROUGHING EXTENDING S INTO 
MEXICO. THE FRONTAL BOUNDARY WILL ENTER THE FAR N WATERS TODAY 
AND SAT BUT IS NOT EXPECTED TO MAKE MUCH PROGRESS SOUTHWARD. IN 
THE MID AND UPPER LEVELS...STRONG WLY FLOW IS ADVECTING MOISTURE 
ACROSS THE AREA BUT IT APPEARS TO BE MAINLY IN THE FORM OF 
MID-HIGH LEVEL CLOUDS.

THE CARIBBEAN SEA...
A WEAK INVERTED SFC TROUGH CONTINUES WESTWARD AT 10-15 KT 
CENTERED ALONG 68W N OF 13N. LOW-MID LEVEL CLOUDINESS AND 
EMBEDDED SHOWERS AND LOW TOPPED TSTMS ARE WITHIN 300 NM E OF THE 
TROUGH AXIS. GUADELOUPE REPORTED 1.22 INCHES OF RAIN MAINLY TIED 
TO THIS TROUGH. PATCHY CLOUDS AND EMBEDDED ISOLATED SHOWERS ARE 
OCCURRING OVER THE ISLAND OF HISPANIOLA ASSOCIATED WITH REMNANT 
TROUGHING AND LOCAL UPSLOPE CONDITIONS. ALL OF THE AREAS 
OUTLINED ARE SHALLOW IN NATURE CAPPED BY DRY AIR IN THE MID AND 
UPPER LEVELS. E TO SE WINDS NEAR 20 KT ARE BLOWING OVER THE NW 
CARIBBEAN DUE TO THE ENHANCED PRES GRADIENT BETWEEN TROUGHING 
OVER S MEXICO AND HIGH PRES OVER THE W ATLC. SIMILAR MAGNITUDE 
NE TO E WINDS ARE OCCURRING IN THE USUAL ZONE NEAR THE COAST OF 
COLOMBIA.  

THE ATLANTIC OCEAN...
A LARGE SCALE MID-UPPER TROUGH OVER THE W ATLC IS FLATTENING 
PROVIDING LIMITED SUPPORT FOR A QUASI-STATIONARY FRONT 
EXTENDING FROM 32N57W TO 25N65W TO W HAITI. ONLY BROKEN 
CLOUDINESS AND ISOLATED SHOWERS ACCOMPANY THE FRONT. THIS 
BOUNDARY IS EXPECTED TO DISSIPATE OVER THE NEXT DAY OR SO AS IT 
CONTINUES TO LOSE UPPER SUPPORT. A WEAK SFC RIDGE IS BUILDING E 
OVER THE W ATLC BEHIND THE FRONT CENTERED NEAR 27N71W. WINDS ARE 
GENERALLY LIGHT ACROSS THE W ATLC BESIDES FOR SW 20-25 KT WINDS 
NEAR THE N BORER BETWEEN BERMUDA AND 73W ENHANCED BY LOW PRES N 
OF THE AREA. FARTHER E...AN UPPER LOW CENTERED NEAR 24N34W IS 
PRODUCING MULTILAYER CLOUDINESS AND EMBEDDED ISOLATED SHOWERS 
FROM 21N-26N BETWEEN 28W-36W. A SW TO W UPPER JET WITH CORE 
WINDS NEAR 100 KT ORIGINATES JUST E OF THE BASE OF THE UPPER 
TROUGH FROM 9N35W TO 17N25W TO 25N15 GENERATING AND ADVECTING 
MID-HIGH LEVEL CLOUDINESS WITHIN 300 NM SE OF THE JET AXIS. 

$$
CANGIALOSI