000
AXNT20 KNHC 201019
TWDAT 

TROPICAL WEATHER DISCUSSION...     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SUN APR 20 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0930 UTC.

...THE ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N10W 4N20W 3N30W CROSSING THE 
EQUATOR NEAR 44W AND INTO NE BRAZIL NEAR 1S47W. A LARGE CLUSTER 
OF MODERATE TO STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF 
THE AXIS BETWEEN THE COAST OF AFRICA AND 13W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS FROM THE AXIS TO 6N 
BETWEEN 19W-30W. WIDESPREAD MODERATE CONVECTION IS FROM 3S-5N W 
OF 37W AND INLAND OVER S AMERICA. 

...DISCUSSION...

GULF OF MEXICO...
A WEAK COLD FRONT EXTENDS ACROSS THE EASTERN AND CENTRAL 
GULF FROM THE CENTRAL FLORIDA COAST NEAR 27N83W ALONG 
26N85W TO 26N90W. AS OF 09Z...THE STATIONARY PORTION OF THE 
FRONTAL BOUNDARY HAS DISSIPATED. THIS BOUNDARY REMAINS DRY IN 
NATURE AND IS NOTED BY A WIND SHIFT RATHER THAN ANY CONVECTION. 
SHIP AND BUOY OBS SHOW N WINDS 5 TO 15 KT BEHIND THE FRONT 
SEPARATED FROM S TO SE WINDS 5 TO 10 KT AHEAD OF THE BOUNDARY IN 
THE EAST GULF. SE RETURN FLOW OF 10 TO 15 KT DOMINATES THE 
CENTRAL AND WEST GULF. EXPECT THE FRONTAL BOUNDARY TO CONTINUE 
MOVING SE CROSSING THE FLORIDA PENINSULA LATER TODAY. 
ALOFT...NWLY FLOW ON THE LEADING EDGE OF AN UPPER RIDGE COVERS 
THE REGION. MODERATE SUBSIDENCE IS MAINTAINING DRY AND STABLE 
CONDITIONS THROUGHOUT THE GULF.
 
CARIBBEAN SEA...
MODERATE TO STRONG EASTERLY TRADE WINDS CONTINUE TO DOMINATE THE 
WEATHER PATTERN IN THE CARIBBEAN WITH THE STRONGEST WINDS ALONG 
THE COAST OF COLOMBIA. ISOLATED LOW-TOPPED TRADE WIND SHOWERS  
CONTINUE TO TREK ACROSS THE EASTERN CARIBBEAN N OF 14N. 
ALOFT...WESTERLY FLOW AT THE BASE OF AN UPPER TROUGH INDUCES 
MODERATE TO STRONG SUBSIDENCE ACROSS THE REGION. UPPER 
MOISTURE/HIGH CLOUDS ARE BEING ADVECTED FROM COLOMBIA ACROSS THE 
LESSER ANTILLES S OF 16N. OTHERWISE...THE CARIBBEAN REMAINS 
RELATIVELY CLEAR. EXPECT THE FRONTAL BOUNDARY CURRENTLY IN THE 
GULF OF MEXICO TO WEAKEN AS IT MOVES SE AND ENTERS THE NW 
CARIBBEAN OVER THE NEXT 24 HOURS. 

ATLANTIC OCEAN...
A NARROW BAND OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS IS 
MOVING OVER THE W ATLC AHEAD OF THE COLD FRONT IN THE GULF OF 
MEXICO...HOWEVER...MOST THUNDERSTORM ACTIVITY REMAINS N OF THE 
DISCUSSION AREA. AS OF 09Z... THE CONVECTION EXTENDED ALONG A 
LINE FROM 30N79W TO 28N80W. UPPER LEVEL DIVERGENCE AT THE 
LEADING EDGE OF A DEEP-LAYERED TROUGH IS ENHANCING AN AREA OF 
MODERATE CONVECTION NW OF THE TURKS AND CAICOS FROM 22N-25N 
BETWEEN 68W-73W. LIGHTNING DATA INDICATE NUMEROUS THUNDERSTORMS 
ASSOCIATED WITH THIS CONVECTION. FARTHER EAST...A SFC TROUGH 
ENTERS THE DISCUSSION AREA NEAR 31N54W AND STRETCHES SW TO NEAR 
23N62W. SCATTERED CLOUDS SURROUND THE TROUGH. THE CENTRAL AND 
EAST ATLC REMAINS TRANQUIL AS ANTICYCLONIC FLOW TRANSPORTS FAIR 
WEATHER CUMULUS CLOUDS AROUND A 1022 MB SFC HIGH CENTERED NEAR 
30N38W. NEAR ZONAL WESTERLY UPPER FLOW IS TRANSPORTING HIGH 
CLOUDS FROM S AMERICA TO AFRICA S OF 16N.

$$
WADDINGTON