000
AXNT20 KNHC 291749
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT TUE SEP 29 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1715 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS INTRODUCED ALONG 20W S OF 14N MOVING W AT 15 
KT. SATELLITE IMAGERY SHOWS AN INVERTED-V LOW LEVEL PATTERN. THE 
SSMI TOTAL PRECIPITABLE WATER ALSO SHOWS A MAXIMUM. WIDELY 
SCATTERED MODERATE CONVECTION IS W OF THE WAVE AXIS FROM 8N-11N 
BETWEEN 22W-25W...AND FROM 4N-6N BETWEEN 20W-24W. 

A TROPICAL WAVE IS ALONG 41W S OF 16N MOVING W AT 15 KT. THE 
SSMI TOTAL PRECIPITABLE WATER SHOWS A MAXIMUM ALONG THE WAVE 
AXIS. SAHARAN DUST SURROUNDS THE WAVE FROM 10N-20N E 0F 45W 
SUPPRESSING CONVECTION W OF THE WAVE AXIS. WIDELY SCATTERED 
MODERATE CONVECTION IS FROM 5N-18N BETWEEN 37W-42W.

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 12N16W 9N23W 8N30W 12N45W 8N60W. 
BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION... 
ISOLATED MODERATE CONVECTION IS FROM 7N-10N BETWEEN 45W-52W... 
AND FROM 9N-12N BETWEEN 55W-60W.  

...DISCUSSION...

THE GULF OF MEXICO...
AS OF 1500 UTC...AN COLD FRONT IS OVER THE N GULF OF MEXICO 
ALONG 29N80W 27N90W 27N97W. SCATTERED SHOWERS AND ISOLATED 
THUNDERSTORMS ARE ALONG AND N OF THE FRONT. SIMILAR CONVECTION 
IS OVER THE FLORIDA KEYS AND THE STRAITS OF FLORIDA FROM 24N-25N 
BETWEEN 80W-83W. MOSTLY FAIR WEATHER IS OVER THE REMAINDER OF 
THE GULF. 10-15 KT NORTHERLY WINDS ARE N OF THE FRONT. IN THE 
UPPER LEVELS...A RIDGE IS PRODUCING NW UPPER LEVEL FLOW OVER THE 
GULF. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE N GULF N OF 
26N. STRONG SUBSIDENCE IS OVER THE REMAINDER OF THE GULF. 
EXPECT...THE COLD FRONT TO EXTEND FROM SOUTH FLORIDA TO S TEXAS 
IN 24 HOURS WITH CONVECTION MOSTLY OVER THE SE GULF. 
 
THE CARIBBEAN SEA...
FRESH TO STRONG TRADEWINDS ARE OVER THE CARIBBEAN SEA AND 
CENTRAL AMERICA. SCATTERED MODERATE CONVECTION IS ALONG THE 
COASTS OF NICARAGUA AND HONDURAS FROM 13N-17N BETWEEN 81W-85W.  
SCATTERED SHOWERS ARE OVER THE E CARIBBEAN E OF 67W...AND OVER 
THE SW CARIBBEAN S OF 12N. MOSTLY FAIR WEATHER IS OVER THE 
REMAINDER OF THE AREA. IN THE UPPER LEVELS...AN UPPER LEVEL 
RIDGE IS OVER THE W CARIBBEAN AND CENTRAL AMERICA W OF 80W. AN 
UPPER LEVEL LOW IS CENTERED N OF N COLOMBIA NEAR 14N74W. 
DIFFLUENCE E OF THE LOW CENTER IS ENHANCING THE SHOWERS OVER THE 
E CARIBBEAN. STRONG SUBSIDENCE IS OVER THE CENTRAL AND NW 
CARIBBEAN. EXPECT...SHOWERS AND THUNDERSTORMS OVER CENTRAL 
AMERICA AND THE W CARIBBEAN OVER THE NEXT 24 HOURS. 

THE ATLANTIC OCEAN...
A COLD FRONT IS OVER THE W ATLANTIC ALONG 32N75W 29N81W. A 
DISSIPATING COLD FRONT IS FURTHER E ALONG 32N68W 26N77W TO 
INCLUDE THE N BAHAMAS. WIDELY SCATTERED MODERATE CONVECTION IS S 
OF THE LATTER FRONT FROM 25N-27N BETWEEN 71W-76W. A 1020 MB HIGH 
IS OVER THE CENTRAL ATLANTIC NEAR 24N54W. THE TAIL END OF A COLD 
FRONT IS OVER THE CENTRAL ATLANTIC ALONG 31N27W 29N30W 28N39W. 
WIDELY SCATTERED MODERATE CONVECTION IS FROM 28N-31N BETWEEN 
23W-28W. A SURFACE TROUGH...THE REMNANTS OF T.D. EIGHT IS OVER 
THE TROPICAL CENTRAL ATLANTIC ALONG 20N50W 15N48W. ANOTHER 
SURFACE TROUGH IS FURTHER S NEAR THE ITCZ FROM 14N48W 5N47W. 
SCATTERED SHOWERS ARE MOSTLY CONFINED TO S OF THE ITCZ. IN 
THE UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE W ATLANTIC N 
OF 20N AND W OF 70W. AN UPPER LEVEL LOW IS OVER THE W ATLANTIC 
NEAR 28N60W. UPPER LEVEL DIFFLUENCE E OF THE CENTER IS 
PRODUCING WIDELY SCATTERED MODERATE CONVECTION IS FROM 27N-32N 
BETWEEN 50W-60W. AN UPPER LEVEL TROUGH IS OVER THE E ATLANTIC N 
OF 20N AND E OF 40W. TWO UPPER LEVEL HIGHS ARE OVER THE TROPICAL 
ATLANTIC NEAR 13N50W AND 10N18W.

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FORMOSA