000
AXNT20 KNHC 092355
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT FRI OCT 09 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 33W S OF 15N MOVING W NEAR 25 KT. 
LOW-LEVEL SATELLITE DERIVED WINDS SHOW CYCLONIC CURVATURE ALONG 
THE WAVE AXIS. A MAXIMUM IN DEEP LAYER MOISTURE IS ALSO OBSERVED 
IN TOTAL PRECIPITABLE WATER IMAGERY BETWEEN 28W-35W. OUTSIDE 
THIS AREA HOWEVER...SAHARAN DUST IS SUPPRESSING CONVECTION N OF 
10N E OF 40W TO THE W AFRICA COAST. SCATTERED MODERATE 
CONVECTION IS FROM 14N-16N BETWEEN 29W-33W.

TROPICAL WAVE IS ALONG 65W S OF 18N MOVING W NEAR 20 KT. VISIBLE 
SATELLITE IMAGERY INDICATES CYCLONIC TURNING IN THE LOW-LEVEL 
CLOUD FIELD ACROSS THE SE CARIBBEAN NEAR THE WAVE AXIS. A 
MAXIMUM IN DEEP LAYER MOISTURE IS ALSO NOTED ON TOTAL 
PRECIPITABLE WATER IMAGERY BETWEEN 60W-68W. SCATTERED MODERATE 
CONVECTION IS INLAND OVER N VENEZUELA FROM 8N-11N BETWEEN 
64W-67W.

TROPICAL WAVE IS OVER CENTRAL AMERICA ALONG 85W S OF 16N MOVING 
W NEAR 20 KT. THE WAVE LIES IN A BROAD AREA OF DEEP LAYER 
MOISTURE ACROSS THE SW CARIBBEAN S OF 17N W OF 76W AS OBSERVED 
IN THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION IS FROM 13N-18N BETWEEN 81W-86W. 

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 10N14W 11N33W 5N50W 5N53W. 
BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION... 
NUMEROUS STRONG CONVECTION IS INLAND OVER WEST AFRICA FROM 
10N-12N BETWEEN 13W-15W. WIDELY SCATTERED MODERATE CONVECTION IS 
FROM 5N-8N BETWEEN 37W-48W. 

...DISCUSSION...

GULF OF MEXICO...
AS OF 2100 UTC...A COLD FRONT IS OVER THE NW GULF OF MEXICO FROM 
LOUISIANA TO NE MEXICO ALONG 29N92W 26N96W 23N98W 26N100W. 
SCATTERED MODERATE CONVECTION IS WITHIN 60 NM BEHIND THE FRONT. 
25-30 KT NORTHERLY WINDS AND UP TO 10 FT SEAS ARE BEHIND THE 
FRONT. FAIR WEATHER AND HIGH PRESSURE RIDGING DOMINATES THE 
REMAINDER OF THE GULF WITH 10-15 KT SW FLOW. IN THE UPPER 
LEVELS...THE LEADING EDGE OF AN UPPER LEVEL TROUGH IS OVER THE W 
GULF W OF 93W. THE REMAINDER OF THE GULF HAS SW UPPER LEVEL FLOW 
FROM THE BACK SIDE OF AN UPPER LEVEL HIGH CENTERED OVER THE W 
ATLANTIC. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE W GULF W 
OF 94W. THE REMAINDER OF THE GULF HAS STRONG SUBSIDENCE. EXPECT 
...THE FRONT TO EXTEND FROM THE FLORIDA PANHANDLE TO THE BAY OF 
CAMPECHE IN 24 HOURS WITH CONVECTION. 

CARIBBEAN SEA...
TWO TROPICAL WAVES ARE OVER CENTRAL AMERICA AND THE CARIBBEAN. 
SEE ABOVE. FRESH TO STRONG TRADEWINDS ARE OVER THE CARIBBEAN 
SEA. WIDELY SCATTERED MODERATE CONVECTION IS OVER PANAMA AND 
COSTA RICA. A FEW SHOWERS ARE OVER THE WINDWARD ISLANDS. IN THE 
UPPER LEVELS...AN UPPER LEVEL LOW IS OVER GUATEMALA NEAR 15N91W. 
UPPER LEVEL DIFFLUENCE E OF THE CENTER IS ENHANCING THE 
CONVECTION OVER THE W CARIBBEAN. EXPECT...MORE CONVECTION OVER 
THE CENTRAL AND WESTERN CARIBBEAN W OF 70W OVER THE NEXT 24 
HOURS AS THE TROPICAL WAVES MOVES W. 

ATLANTIC OCEAN...
A 1020 MB HIGH IS OVER THE W ATLANTIC NEAR 33N71W. THE TAIL END 
OF A COLD FRONT IS OVER THE CENTRAL ATLANTIC ALONG 32N43W 27N50W 
26N60W. FURTHER S...A 1018 MB HIGH IS OVER THE CENTRAL ATLANTIC 
NEAR 22N48W. THE REMNANTS OF HENRI IS NOW A SURFACE TROUGH N OF 
THE LEEWARD ISLANDS ALONG 25N60W 20N65W. ANOTHER 1024 MB HIGH IS 
OVER THE E ATLANTIC NEAR 38N17W. IN THE UPPER LEVELS...AN UPPER 
LEVEL HIGH IS OVER THE W ATLANTIC NEAR 29N72W. AN UPPER LEVEL 
LOW IS CENTERED NEAR 34N45W. ANOTHER UPPER LEVEL LOW IS CENTERED 
NEAR 23N34W. AN UPPER LEVEL HIGH IS OVER THE TROPICS NEAR 
10N37W.   

$$
FORMOSA