000
AXNT20 KNHC 092305
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST SAT FEB 09 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 6N9W 2N14W 1N24W 2N41W 3N52W. 
SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 60 NM OF LINE 
FROM 2N14W TO EQ11W. SMALL CLUSTERS OF SCATTERED MODERATE 
CONVECTION ARE FROM 3N TO THE EQUATOR BETWEEN 5W-30W. 

...DISCUSSION...

GULF OF MEXICO...
THE DEEP LAYERED TROUGH COVERS THE E HALF OF THE US AND INTO THE 
NW ATLC WITH A SHORTWAVE UPPER TROUGH IS MOVING INTO THE N GULF 
COAST. THE LEADING FRONTAL BOUNDARY EXTENDS ACROSS S FLORIDA 
JUST S OF LAKE OKEECHOBEE TO 24N90W AND IS LOSING ITS 
DEFINITION BUT CONTINUES TO GENERATE SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS OVER THE GULF WITHIN 120 NM S OF THE BOUNDARY. A 
SECOND SURGE ASSOCIATED WITH THE SHORTWAVE TROUGH ENTERS THE 
GULF OVER PENSACOLA FLORIDA WESTWARD ACROSS THE MISSISSIPPI 
DELTA TO INLAND OVER TEXAS NEAR CORPUS CHRISTI. THIS FRONT IS 
EMBEDDED WITHIN SOMEWHAT DRIER AIR AND IS NOT PRODUCING ANY 
SHOWER ACTIVITY BUT IS DROPPING DEW POINTS ACROSS THE AREA. 

CARIBBEAN SEA...
AN UPPER RIDGE EXTENDS ACROSS THE NW CARIBBEAN FROM CENTRAL 
AMERICA TO CENTRAL CUBA. AN UPPER TROUGH AXIS EXTENDS ACROSS THE 
LESSER ANTILLES NEAR MARTINIQUE NW ACROSS HAITI TO THE E TIP OF 
CUBA DOMINATING THE REMAINDER OF THE CARIBBEAN. THE SURFACE 
RIDGE OVER THE ATLC COUPLED WITH THE LOWER PRESSURE OVER SOUTH 
AMERICA IS PRODUCING A RATHER TIGHT PRESSURE GRADIENT OVER THE 
CARIBBEAN AND IS GENERATING MODERATE/STRONG SURFACE EASTERLY 
TRADE WINDS ACROSS THE AREA. MODERATE/STRONG SUBSIDENCE AND DRY 
AIR UPPER AIR ARE LIMITING ANY THUNDERSTORMS ACROSS THE AREA. 
HOWEVER...THE TRADE WINDS ARE USHERING IN SOME LOW LEVEL CLOUDS 
AND SCATTERED LOW LEVEL SHOWERS. 
 
ATLANTIC OCEAN...
THE DEEP LAYERED TROUGH OVER THE E US AND NW ATLC EXTENDS A 
WEAKENING ASSOCIATED STATIONARY FRONT INTO THE REGION THROUGH 
32N73W TO ACROSS THE FLORIDA PENINSULA JUST S OF LAKE 
OKEECHOBEE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 
45 NM OF THE FRONT. AN UPPER TROUGH IS OVER THE FAR E ATLC N OF 
19N E OF 24W TO INLAND OVER W AFRICA WITH THE UPPER LOW NEAR 
31N15W. THE ASSOCIATED COLD FRONT EXTENDS FROM A 1009 MB LOW 
NEAR 27N18W ALONG 25N17W THEN W ALONG 23N23W TO 24N26W. A WARM 
FRONT EXTENDS FROM THE SURFACE LOW ACROSS THE CANARY ISLANDS TO 
NEAR 29N14W. SCATTERED SHOWERS AND WIDELY ISOLATED THUNDERSTORMS 
ARE N OF 30N BETWEEN 14W-18W. THE CENTRAL ATLC IS DOMINATED BY 
DEEP LAYERED RIDGE WITH THE SURFACE RIDGE ANCHORED BY A 1025 MB 
HIGH NEAR 28N51W. AN E/W UPPER RIDGE EXTENDS ACROSS THE TROPICAL 
ATLC ALONG 4N/5N TO 40W AND A WEAKENING JETSTREAM WITH WINDS OF 
90 TO 110 KT IS ALONG THE N PERIPHERY OF THE RIDGE WITHIN 150 NM 
OF LINE FROM 14N35W TO INLAND OVER W AFRICA NEAR 19N16W.  
    
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WALLACE