000
AXNT20 KNHC 292331
TWDAT 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT TUE APR 29 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 
SECTIONS OF SOUTH AMERICA...AND THE 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
2245 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 4N4W 1N18W 2N32W CROSSING THE 
EQUATOR NEAR 41W TO 2S50W. CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION ARE FROM 4N TO THE EQUATOR 
BETWEEN THE PRIME MERIDIAN TO 10W AND FROM 2N TO S OF THE 
EQUATOR BETWEEN 10W-26W. CLUSTERS OF SCATTERED MODERATE 
CONVECTION ARE FROM 4N TO S OF THE EQUATOR E OF 30W TO INLAND 
OVER SOUTH AMERICA. 

...DISCUSSION...

GULF OF MEXICO...
BROAD DEEP LAYERED TROUGH COVERS THE E US AND THE N GULF N OF 
25N INTO THE W ATLC. THE ASSOCIATED COLD FRONT IS MOVING OUT OF 
THE GULF EXTENDING ACROSS THE FLORIDA STRAITS NEAR 25N80W ACROSS 
W CUBA NEAR HAVANA INTO THE NW CARIBBEAN. A BROAD UPPER RIDGE 
OVER THE CARIBBEAN COVERS THE SE GULF BRINGING TROPICAL MOISTURE 
WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS 
ACROSS S MEXICO AND THE YUCATAN AND THE SE GULF S OF A LINE 
FROM FORT MYERS FLORIDA TO THE CENTRAL BAY OF CAMPECHE. A 
SURFACE RIDGE IS BUILDING OVER THE W GULF WITH A 1023 MB HIGH 
OFF THE LOUISIANA COAST NEAR 28N92W. A SMOKE PLUME INDICATED BY 
NOAA FIRE DETECTION COVERS WITHIN 120 NM ALONG THE NE COAST FROM 
SE LOUISIANA ACROSS THE N FLORIDA PANHANDLE INTO THE W ATLC WITH 
A DENSE AREA SHOWING ON RADAR COVERING THE FAR NE GULF N OF 27N 
E OF 85W. OTHERWISE STRONG SUBSIDENCE AND DRY AIR COVER THE 
REMAINDER OF THE N GULF GIVING THE AREA CLEAR SKIES. 

CARIBBEAN SEA...
BROAD UPPER RIDGE COVERS THE CARIBBEAN ANCHORED BY AN UPPER HIGH 
ALONG THE N COAST OF COLOMBIA DRAWING TROPICAL MOISTURE ACROSS 
CENTRAL AMERICA OVER THE W CARIBBEAN WITH STRONG SUBSIDENCE AND 
DRY UPPER AIR OVER THE E CARIBBEAN. A COLD FRONT ASSOCIATED WITH 
THE DEEP LAYERED TROUGH OVER THE N GULF OF MEXICO ENTERS THE NW 
CARIBBEAN ACROSS CUBA NEAR HAVANA TO OVER THE YUCATAN JUST N OF 
BELIZE TO NW GUATEMALA PRODUCING SCATTERED SHOWERS AND POSSIBLE 
ISOLATED THUNDERSTORMS N OF THE FRONT. A WEAK SURFACE TROUGH IS 
IN THE CENTRAL CARIBBEAN JUST W OF JAMAICA EXTENDING ALONG 
78W/79W FROM 14N-20N PRODUCING ISOLATED SHOWERS WITHIN 75 NM 
EITHER SIDE OF THE TROUGH AXIS. THE SOUTHERLY UPPER LEVEL FLOW 
OVER THE SW CARIBBEAN IS GENERATING SCATTERED SHOWERS WITH 
ISOLATED THUNDERSTORMS AS INDICATED BY LIGHTENING DATA S OF S OF 
11N FROM OVER COLOMBIA TO OVER CENTRAL AMERICA. MODERATE/STRONG 
NE TO E TRADE WINDS COVER THE MOST OF THE CARIBBEAN WITH THE 
EXCEPTION NW OF THE FRONT. 

ATLANTIC OCEAN...
DEEP LAYERED TROUGH THAT COVERS THE N GULF OF MEXICO AND THE E 
US EXTENDS OVER THE NW ATLC WITH THE ASSOCIATED COLD FRONT 
ENTERING THE REGION 32N72W EXTENDING ACROSS THE N BAHAMA ISLANDS 
AND THROUGH THE FLORIDA STRAITS NEAR 25N80W CONTINUING INTO THE 
NW CARIBBEAN. BROAD UPPER RIDGE THAT COVERS THE CARIBBEAN 
EXTENDS INTO THE W AND CENTRAL ATLC ACROSS HISPANIOLA TO BEYOND 
32N62W BRINGING UPPER LEVEL MOISTURE ACROSS THE SE GULF OF 
MEXICO/NW CARIBBEAN TO OVER THE W ATLC GENERATING SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 150 NM EITHER 
SIDE OF THE FRONT. AFTERNOON SHOWERS AND ISOLATED THUNDERSTORMS 
AS INDICATED BY LIGHTENING DATA ARE BEING GENERATED OVER S 
FLORIDA AND CUBA E OF THE FRONT MOVING TO ALONG THE IMMEDIATE 
COASTLINES. SURFACE HIGH PRESSURE COVERS THE W AND CENTRAL ATLC 
E OF THE FRONT TO 55W WITH A 1020 MB HIGH LOCATED NEAR 26N62W. A 
DEEP LAYERED TROUGH IS OVER THE REMAINDER OF THE CENTRAL ATLC 
WITH THE UPPER LOW CENTERED N OF THE REGION NEAR 35N47W AND A 
1000 MB SURFACE LOW NEAR 35N48W. A SURFACE TROUGH EXTENDS INTO 
THE REGION THROUGH 32N39W S ALONG 28N41W THEN SW TO 20N54W WITH 
ISOLATED SHOWERS WITHIN 90 NM EITHER SIDE OF THE SURFACE TROUGH. 
BROAD UPPER RIDGE COVERS THE E ATLC WITH THE AXIS ALONG 24W 
EXTENDING TO 31N WITH A DEEP LAYERED LOW/TROUGH INLAND OVER W 
AFRICA. A WEAK SURFACE TROUGH IS BENEATH THE UPPER RIDGE 
EXTENDING FROM 25N25W TO 31N29W. 

$$
WALLACE