000
AXNT20 KNHC 061039
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON APR 06 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1015 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 6N10W 3N17W CROSSING THE EQUATOR 
NEAR 22W AND EXTENDING TO 2S30W INTO NE BRAZIL NEAR 3S42W. 
SCATTERED MODERATE CONVECTION IS FROM 1N TO 6N BETWEEN 11W AND 
15W. SCATTERED MODERATE CONVECTION IS S OF 3N BETWEEN 20W AND 
25W.

...DISCUSSION...

THE GULF OF MEXICO...
A STRONG FRONT FOR THIS TIME OF YEAR IS ON THE MOVE EXTENDING 
FROM THE FLORIDA PANHANDLE TO S MEXICO ALONG 30N85W 24N90W 
18N95W. STRONG N WINDS FOLLOW THE FRONT DUE TO THE TIGHT PRES 
GRADIENT BETWEEN IT AND A 1038 MB HIGH BUILDING S FROM CANADA. 
WINDS ARE ESTIMATED TO BE UP TO GALE FORCE BEHIND THE FRONT OVER 
THE SW WATERS...WHERE LOCAL TOPOGRAPHY PROVIDES AN ENHANCEMENT. 
THESE WINDS HAVE ELEVATED SEAS TO 10 FT ACROSS THE NW GULF BUOYS 
AND LIKELY A FEW FT HIGHER OVER THE SW GULF WHERE THE FETCH IS 
GREATER AND WINDS ARE LIKELY STRONGER. LITTLE SIGNIFICANT 
MOISTURE IS ASSOCIATED WITH THE FRONT...IN PART CAPPED BY 
WIDESPREAD STABILITY IN THE MID-LEVELS. THE AIR IS SUBSTANTIALLY 
COOLER AND DRIER W OF THE FRONT WITH TEMPS IN THE 40'S/50'S F 
AND DEWPTS IN THE 30'S F OVER THE N GULF COAST (COMPARED WITH 
70'S F TEMPS AND DEWPTS OVER MUCH OF FLORIDA). THE BOUNDARY IS 
EXPECTED TO CLEAR THE ENTIRE AREA BY THIS EVENING.

THE CARIBBEAN SEA...
A WEAK SFC TROUGH IS MOVING SLOWLY W CENTERED ALONG 68W N OF 
15N. SATELLITE IMAGERY AND SAN JUAN DOPPLER RADAR SHOW AN AREA 
OF LOW-MID LEVEL CLOUDINESS WITH EMBEDDED SCATTERED SHOWERS AND 
ISOLATED TSTMS N OF 14N BETWEEN 63W-69W. FAIR WEATHER DOMINATES 
THE REMAINDER OF THE REGION ENHANCED BY A STRONGLY SUBSIDENT 
ENVIRONMENT BETWEEN AMPLIFIED UPPER RIDGING OVER THE TROPICAL 
EPAC AND TROUGHING OVER THE CENTRAL ATLC. RECENT QSCAT DATA AND 
SFC OBS DEPICT LIGHT TO MODERATE TRADES...EXCEPT FOR THE GULF OF 
HONDURAS AND NEAR THE COAST OF COLOMBIA. LOOKING AHEAD...THE 
WEAK TROUGH MENTIONED IS EXPECTED TO CONTINUE W-NW MOVING OVER 
HISPANIOLA LATER TODAY. MEANWHILE...A STRONG FRONT FOR THIS TIME 
OF YEAR IS EXPECTED TO MOVE INTO THE NW CARIBBEAN TONIGHT.

THE ATLANTIC OCEAN...
IR IMAGERY AND LIGHTNING DATA DEPICT AN AREA OF SCATTERED 
SHOWERS AND TSTMS BETWEEN THE SE CONUS AND BERMUDA N OF 28N 
BETWEEN 71W-76W. THIS ACTIVITY IS BEING TRIGGERED BY A MID-LEVEL 
VORTICITY MAXIMUM THAT IS DIVING SE INTO A TROUGH OVER THE 
CENTRAL ATLC. THAT TROUGH IS PROVIDING SOME SUPPORT FOR A 
QUASI-STATIONARY FRONT THAT EXTENDS FROM 32N60W TO 24N69W.  
UPPER DIFFLUENCE E OF THE TROUGH AXIS IS PRODUCING ISOLATED  
SHOWERS AND TSTMS N OF 23N BETWEEN 56W-60W. FARTHER E...AN 
ELONGATED UPPER TROUGH EXTENDING ALONG 29N/30N E OF 40W IS 
PROVIDING VERY LIMITED SUPPORT FOR A BENIGN WEAK SFC TROUGH 
ALONG 32N44W 26N42W. THIS FEATURE WILL LIKELY DISSIPATE LATER 
TODAY. OVER THE DEEP TROPICS...THE MAIN FEATURE IS A LARGE UPPER 
HIGH CENTERED NEAR 10N17W. ONLY ASSOCIATED EFFECTS EXIST ON ITS 
WRN PERIPHERY WHERE UPPER SLY FLOW AND AN OVERALL DIFFLUENT 
PATTERN IS GENERATING AND SPREADING MOISTURE N FROM THE ITCZ S 
OF 11N BETWEEN 40W-56W.  

$$
CANGIALOSI