000
AXNT20 KNHC 161016
TWDAT 

TROPICAL WEATHER DISCUSSION...     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT WED APR 16 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
0945 UTC.

...THE ITCZ...

ITCZ AXIS IS CENTERED ALONG 5N8W 1N20W CROSSING THE EQUATOR NEAR 
32W TO 1S40W THEN INTO NE BRAZIL NEAR 1S49W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION FROM THE EQUATOR TO THE AXIS 
BETWEEN 4W-10W. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE 
FROM 3S-4N BETWEEN 18W-24W.

...DISCUSSION...

GULF OF MEXICO...
STRATOCUMULUS CLOUDS REMAIN SCATTERED ACROSS THE GULF...EXCEPT E 
OF 84W WHERE NLY FLOW AROUND A SFC RIDGE HAS PUSHED THE MOISTURE 
OUT OF THE AREA...AND W OF 95W WHERE THE AIRMASS HAS BEEN 
MODIFIED BY S TO SE RETURN FLOW. ALOFT...CONFLUENCE AT THE BASE 
OF AN UPPER TROUGH OVER THE W ATLC IS CREATING STRONG SUBSIDENCE 
AND A VERY DRY AIRMASS OVER THE NORTHERN GULF WATERS. NEAR ZONAL 
FLOW TO THE SOUTH IS ADVECTING UPPER-LEVEL MOISTURE FROM THE 
PACIFIC ACROSS THE SW GULF. EXPECT THE WEATHER PATTERN IN THE 
GULF TO REMAIN FAIRLY TRANQUIL OVER THE NEXT DAY OR TWO BEFORE 
THE NEXT FRONT MOVES OFF THE TEXAS COAST EARLY THIS WEEKEND.

CARIBBEAN SEA...
THE LEADING OF TWO COLD FRONTS IN THE CARIBBEAN IS BEGINNING TO 
DIMINISH AS THE SECONDARY SURGE BECOMES DOMINANT. AS OF 
09Z...THE LEADING FRONT WAS ANALYZED FROM NEAR 19N72W TO 16N78W. 
THE SECONDARY SURGE STRETCHED FROM SE CUBA NEAR 20N76W TO 
SOUTHERN BELIZE NEAR 16N89W. MOST OF THE CONVECTION ASSOCIATED 
WITH THESE BOUNDARIES IS CONFINED TO THE W ATLC LEAVING ONLY 
PATCHY CLOUDS IN THE CARIBBEAN. EXPECT THE FRONTS TO MERGE IN 
THE NEXT 12 HOURS OR SO. MOST CONVECTIVE ACTIVITY IN THE 
CARIBBEAN IS ASSOCIATED WITH A SFC TROUGH THAT LIES ALONG 80W 
FROM 15N TO THE PANAMA/COSTA RICA BORDER. LOW CLOUDS AND 
SCATTERED SHOWERS ARE WITHIN 100 NM OF THE TROUGH. DIVERGENCE 
AROUND AN UPPER LEVEL HIGH OVER THE GULF OF MOSQUITOES IS 
ENHANCING CONVECTION AT THE SFC. ELSEWHERE IN THE 
CARIBBEAN...EASTERLY TRADES DOMINATE THE REGION USHERING IN 
LOW-LEVEL CLOUDS AND ISOLATED SHOWERS.

ATLANTIC OCEAN...
HIGH WINDS AND ROUGH SEAS CONTINUE TO DOMINATE THE W ATLC DUE TO 
A 1007 MB SFC LOW CENTERED NEAR 29N75W. SHIP AND BUOY OBS 
CONTINUE TO INDICATE GALE FORCE WINDS WITHIN 210 NM W OF THE LOW 
CENTER. THESE WINDS ARE EXPECTED TO WEAKEN TO BELOW GALE FORCE 
AS THE LOW TRACKS N OVER THE NEXT 6 HOURS. NUMEROUS SHOWERS AND 
THUNDERSTORMS SURROUND THE LOW N OF 26N W OF 67W. FARTHER 
EAST...TWO COLD FRONTS REMAIN IN THE W ATLC. AS OF 09Z...THE 
LEADING BOUNDARY ENTERS THE W ATLC NEAR 31N62W AND EXTENDS SW TO 
THE HAITI/DOMINICAN REPUBLIC BORDER. A THIN BAND OF LOW LEVEL 
CLOUDS WITH EMBEDDED SHOWERS AND THUNDERSTORMS EXTENDS UP TO 60 
NM BEHIND THE BOUNDARY. THE SECOND BOUNDARY EXTENDS FROM 31N65W 
ALONG 25N70W TO NE CUBA NEAR 21N75W. LITTLE THUNDERSTORM 
ACTIVITY IS ASSOCIATED WITH THIS SECOND BOUNDARY...HOWEVER 
MULTI-LEVEL CLOUDS AND SCATTERED SHOWERS COVER THE AREA BETWEEN 
THE TWO FRONTS. THE LEADING FRONT IS SLOW MOVING AND IS EXPECTED 
TO MERGE WITH THE SECONDARY SURGE LATER TODAY.  

THE CENTRAL AND E ATLC IS RATHER TRANQUIL DUE TO A BROAD DEEP 
LAYER RIDGE ANCHORED BY A 1027 MB SFC HIGH CENTERED NEAR 32N40W. 
ANTICYCLONIC FLOW AROUND THE RIDGE CONTINUES TO TRANSPORT FAIR 
WEATHER CUMULUS ACROSS THE ATLANTIC. STRONG WLY UPPER FLOW 
BETWEEN AN ELONGATED UPPER TROUGH OVER W AFRICA AND A FLAT UPPER 
RIDGE OVER THE TROPICS IS SPREADING A PLUME OF HIGH LEVEL 
CLOUDINESS S OF 17N. 

$$
WADDINGTON