000
AXNT20 KNHC 091104 CCA
TWDAT 

TROPICAL WEATHER DISCUSSION...COR
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI OCT 09 2009

CORRECTION TO THE PARAGRAPH ABOUT THE 60W/61W 
TROPICAL WAVE AND A REFERENCE TO BARBADOS...
THE REFERENCE SHOULD BE TO TOBAGO

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1015 IMAGERY.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 27W/28W TO THE SOUTH
OF 15N MOVING WESTWARD 15 TO 20 KT. POSSIBLE SHOWERS FROM 10N
TO 14N BETWEEN 27W AND 30W. THIS COMPARATIVELY MUCH SMALLER
AREA OF CLOUDS/PRECIPITATION IS MOVING TOWARD AN AREA OF
PRECIPITATION THAT IS COMPARATIVELY MUCH BIGGER IN SIZE.

A TROPICAL WAVE IS ALONG 60W/61W TO THE SOUTH OF 19N MOVING 
WESTWARD 20 KT. STRONG SHOWERS AND THUNDERSTORMS COVER TRINIDAD
ENTIRELY...AND POSSIBLY FOR ANOTHER 20 NM TO 30 NM AROUND THE 
WHOLE ISLAND. THE CLOUD TOPS FROM THIS PRECIPITATION REACH 
TOBAGO TO THE NORTH AND COASTAL VENEZUELA TO THE SOUTH.
ISOLATED MODERATE SHOWERS...SOME DISSIPATING WITH TIME...
FROM 15N TO 16N BETWEEN 58W AND 61W.

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 80W/81W TO THE SOUTH OF 
16N MOVING WESTWARD 15 KT. THIS WAVE IS MOVING THROUGH AN AREA 
IN WHICH ITS POSITION IS NEARLY EXACTLY IN THE MIDDLE OF TWO 
UPPER LEVEL CYCLONIC CIRCULATION CENTERS. ONE CENTER IS NEAR 
15N75W AND THE OTHER ONE IS NEAR 13N89W. A LARGE CYCLONIC 
ENVELOPE COVERS THE CARIBBEAN SEA TO THE SOUTH OF 20N.
STRONG SHOWERS AND THUNDERSTORMS ARE WITHIN 30 NM TO 45 NM ON
EITHER SIDE OF THE LINE FROM THE GULF OF URABA NEAR COLOMBIA
TO 10N78W TO 11N81W TO 14N85W. STRONG SHOWERS AND THUNDERSTORMS
ARE ON THE EASTERN PACIFIC OCEAN SIDE OF COSTA RICA. LOW LEVEL 
SPEED CONVERGENCE IN THE TRADEWIND FLOW IS PART OF THE EQUATION 
IN THE DEVELOPMENT OF THE STRONG DEEP CONVECTIVE PRECIPITATION 
IN THE SOUTHWESTERN CARIBBEAN SEA.

...THE ITCZ...

FROM 11N14W TO 11N26W TO 6N40W TO 6N55W ALONG THE NORTHERN COAST 
OF SURINAME. STRONG SHOWERS AND THUNDERSTORMS FROM 6N TO 10N 
BETWEEN 28W AND 40W. ISOLATED MODERATE SHOWERS ARE ELSEWHERE 
FROM 5N TO 10N BETWEEN THE AFRICA COAST AND 16W...AND FROM 2N
TO 12N BETWEEN 23W AND 60W. THE PRECIPITATION THAT IS FROM 10N 
TO 16N BETWEEN 57W AND 60W APPEARS TO BE WEAKENING DUE TO UPPER 
LEVEL DIFFLUENT FLOW AND SHEAR.

...DISCUSSION...

THE GULF OF MEXICO...
BROAD UPPER LEVEL ANTICYCLONIC WIND FLOW AND DRY AIR IN 
SUBSIDENCE COVER THE ENTIRE AREA. ISOLATED SHOWERS THAT ARE
TO THE EAST OF 90W ARE BEING PUSHED WESTWARD IN THE UPPER
LEVEL ANTICYCLONIC FLOW.

THE CARIBBEAN SEA...
ONE UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 15N75W.
A SECOND UPPER LEVEL CYCLONIC CENTER IS NEAR 13N89W. A LARGE 
CYCLONIC ENVELOPE COVERS THE CARIBBEAN SEA TO THE SOUTH OF 20N. 
A CARIBBEAN SEA TROPICAL WAVE IS ALONG 80W/81W TO THE SOUTH OF 
16N MOVING WESTWARD 15 KT. THIS WAVE IS MOVING THROUGH THE 
CYCLONIC ENVELOPE. STRONG SHOWERS AND THUNDERSTORMS ARE WITHIN 
30 NM TO 45 NM ON EITHER SIDE OF THE LINE FROM THE GULF OF URABA 
NEAR COLOMBIA TO 10N78W TO 11N81W TO 14N85W. STRONG SHOWERS AND 
THUNDERSTORMS ARE ON THE EASTERN PACIFIC OCEAN SIDE OF COSTA 
RICA. LOW LEVEL SPEED CONVERGENCE IN THE TRADEWIND FLOW IS PART 
OF THE EQUATION IN THE DEVELOPMENT OF THE STRONG DEEP CONVECTIVE 
PRECIPITATION IN THE SOUTHWESTERN CARIBBEAN SEA.

THE ATLANTIC OCEAN...
THE 1013 MB REMNANT LOW PRESSURE CENTER OF HENRI IS NEAR 21N63W 
MOVING NORTHWEST 10 KT. THE REMNANT OF HENRI IS IN A SURFACE 
TROUGH NOW THAT EXTENDS FROM 24N60W TO 22N62W TO 21N63W 19N65W. 
ISOLATED MODERATE SHOWERS AND THUNDERSTORMS COVER THE AREA FROM 
20N TO 23N BETWEEN 62W AND 65W. THE REMNANT LOW CENTER IS IN AN 
AREA OF BROAD UPPER LEVEL ANTICYCLONIC FLOW AND DRY AIR IN 
SUBSIDENCE. THIS REMNANT CENTER ALSO IS JUST TO THE WEST OF 
BROAD UPPER LEVEL ANTICYCLONIC FLOW AND DRY AIR IN SUBSIDENCE 
ARE TO THE NORTH OF 20N TO THE WEST OF 60W. AN UPPER LEVEL 
TROUGH PASSES THROUGH 32N51W TO 26N52W TO 19N62W. STRONG SHOWERS 
AND THUNDERSTORMS ARE WITHIN 60 NM ON EITHER SIDE OF 27N51W 
BEYOND 32N45W. AN UPPER LEVEL TROUGH PASSES THROUGH 32N36W TO 
25N39W TO 18N39W. ISOLATED MODERATE SHOWERS ARE FROM 22N TO 30N
BETWEEN 35W AND 38W.

$$
MT