000
AXNT20 KNHC 312348
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT TUE MAR 31 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 5N9W 2N17W 1N30W CROSSING THE 
EQUATOR NEAR 33W AND INTO NE BRAZIL NEAR 4S39W. SCATTERED 
MODERATE IS FROM THE EQUATOR TO 6N BETWEEN 10W-15W. SIMILAR 
CONVECTION IS WITHIN 200 NM OF THE COAST OF NE BRAZIL BETWEEN 
46W-51W.

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT IS OVER THE LOWER MISSISSIPPI RIVER VALLEY AND 
ENTERS THE GULF ALONG THE S/CENTRAL LOUISIANA COAST NEAR 30N93W 
AND AS OF 2100 UTC EXTENDS ALONG 28N94W 25N96W 22N96W TO INLAND 
OVER ERN MEXICO NEAR TUXPAN. A PRE-FRONTAL TROUGH IS ALSO 
ANALYZED FROM MOBILE BAY SW ALONG 29N90W 27N94W. NUMEROUS 
SHOWERS AND SCATTERED TSTMS ARE ACROSS THE SE CONUS...INCLUDING 
THE FLORIDA PANHANDLE AND NRN GULF N OF 27N. IN ADDITION TO THE 
ACTIVITY ACROSS THE NRN GULF...CONVERGENT SEABREEZE FLOW IS 
ACROSS THE FLORIDA PANHANDLE AND IS GENERATING SCATTERED SHOWERS 
AND TSTMS PRIMARILY OVER THE ERN HALF OF THE PENINSULA. 
ELSEWHERE ACROSS THE REMAINDER OF THE GULF...A TIGHT PRESSURE 
GRADIENT BETWEEN HIGH PRESSURE IN THE W ATLC AND THE DEEP TROUGH 
OVER THE CENTRAL CONUS AND WRN GULF OF MEXICO ARE PRODUCING 
STRONG SOUTHERLY WINDS UP TO 25 KT ACROSS THE REGION. EXPECT THE 
FRONT TO CONTINUE PROGRESSING SLOWLY EWD AND BECOME DIFFUSE BY 
EARLY THURSDAY.

CARIBBEAN SEA...
THE CARIBBEAN SEA REMAINS FAIRLY TRANQUIL WITH FRESH EASTERLY 
TRADES OBSERVED ACROSS THE ENTIRE BASIN. ABUNDANT DRY AIR AND 
STRONG SUBSIDENCE IN THE UPPER LEVELS IS PREVENTING ANY 
SIGNIFICANT CONVECTION BEYOND PATCHY LOW CLOUDS AND ISOLATED 
LOW-LEVEL SHOWERS OVER THE WINDWARD ISLANDS AND PUERTO 
RICO...INCLUDING THE MONA PASSAGE. LITTLE CHANGE IS EXPECTED 
DURING THE NEXT DAY OR TWO UNDER NEARLY ZONAL FLOW ALOFT.

ATLANTIC OCEAN...
A STRONG LOW PRESSURE SYSTEM IN THE NORTH ATLANTIC EXTENDS A 
COLD FRONT INTO THE DISCUSSION AREA THAT ENTERS THE REGION NEAR 
32N56W AND CONTINUES SW ALONG 30N59W 27N65W TO 27N69W WHERE IT 
BECOMES STATIONARY OVER THE NRN BAHAMAS BEFORE INTERSECTING THE 
FLORIDA PENINSULA NEAR WEST PALM BEACH. SCATTERED SHOWERS ARE 
WITHIN 50 NM OF THE BOUNDARY. DOPPLER RADAR AND LIGHTNING DATA 
ALSO INDICATES SCATTERED SHOWERS AND TSTMS LINGERING OVER THE 
ERN FLORIDA PENINSULA. TO THE EAST...HIGH PRESSURE DOMINATES THE 
CENTRAL AND ERN ATLC. A 1020 MB SURFACE HIGH IS CENTERED NEAR 
28N42W WHILE ANOTHER 1022 MB SURFACE HIGH IS CENTERED E OF THE 
AZORES NEAR 36N19W. DIVERGENCE AROUND AN UPPER LEVEL HIGH OVER W 
AFRICA IS SUPPORTING THE CONVECTION ASSOCIATED WITH THE ITCZ E 
OF 15W.

$$
HUFFMAN