000
AXNT20 KNHC 122354
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED AUG 12 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.

...SPECIAL FEATURES...
THE CENTER OF TROPICAL DEPRESSION TWO IS NEAR 14.3N 35.0W OR
ABOUT 710 MILES/1140 KM TO THE WEST OF THE SOUTHERNMOST CAPE 
VERDE ISLANDS...MOVING WESTWARD 12 KT. THE ESTIMATED MINIMUM
CENTRAL PRESSURE IS 1006 MB. THE MAXIMUM SUSTAINED WIND SPEEDS 
ARE 30 KT WITH GUSTS TO 40 KT. PLEASE READ THE LATEST NHC 
ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE 
PUBLIC BULLETIN UNDER MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. 
SLOW STRENGTHENING IS POSSIBLE...AND THE DEPRESSION MAY BECOME
A TROPICAL STORM DURING THE NEXT DAY OR TWO. WARMING CLOUD TOP 
TEMPERATURES AND DISSIPATING PRECIPITATION FROM 12N TO 14N 
BETWEEN 35W AND 38W.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 19W/20W TO THE SOUTH
OF 22N MOVING WESTWARD 15 KT. SHOWERS AND THUNDERSTORMS ARE
FROM 14N TO 15N BETWEEN 18W AND 19W.

AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 60W/61W TO THE 
SOUTH OF 22N MOVING WESTWARD 15 KT. SCATTERED MODERATE SHOWERS 
TO LOCALLY STRONG THUNDERSTORMS ARE FROM 17N TO 22N BETWEEN 60W 
AND 65W...MOSTLY FROM THE CARIBBEAN SEA ISLANDS NORTHWARD.

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 71W/72W TO THE SOUTH OF 
21N MOVING WESTWARD 10 TO 15 KT. NO SIGNIFICANT DEEP CONVECTIVE
PRECIPITATION IS DIRECTLY RELATED TO THIS WAVE.

A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 84W/85W TO THE 
SOUTH OF 21N MOVING WESTWARD 15 TO 20 KT. SHOWERS AND 
THUNDERSTORMS ARE CONFINED TO CENTRAL NICARAGUA.

...THE ITCZ...

10N21W 12N32W 13N36W 10N46W 14N60W. ISOLATED MODERATE SHOWERS
TO LOCALLY STRONG THUNDERSTORMS ARE WITHIN 90 NM TO 150 NM ON
EITHER SIDE OF 9N13W 9N30W 10N40W 10N50W 15N60W.

...DISCUSSION...

THE GULF OF MEXICO...
UPPER LEVEL CYCLONIC FLOW COVERS THE AREA FROM THE EASTERN 
PACIFIC OCEAN TO MEXICO AND THE SOUTHWESTERN GULF OF MEXICO
11N TO 22N BETWEEN 93W AND 106W. ISOLATED MODERATE SHOWERS ARE 
IN THE AREA THAT IS ENCOMPASSED BY THE CYCLONIC FLOW. UPPER
LEVEL CYCLONIC FLOW COVERS THE GULF OF MEXICO TO THE NORTH OF 
22N TO THE EAST OF 90W. A SHEAR AXIS EXISTS BETWEEN THE CYCLONIC 
FLOW IN THE EASTERN GULF OF MEXICO AND THE CYCLONIC FLOW IN THE 
SOUTHWESTERN CORNER OF THE AREA. SHOWERS AND THUNDERSTORMS FROM
25N TO 27N BETWEEN 90W AND 93W HAVE DEVELOPED IN AN AREA OF 
UPPER LEVEL DIFFLUENT FLOW. A SURFACE TROUGH PASSES THROUGH 
NORTH CENTRAL FLORIDA INTO THE NORTH CENTRAL GULF OF MEXICO
TO A SPOT THAT IS ABOUT 100 NM TO THE EAST OF THE DEEP SOUTH
OF TEXAS. STRONG SHOWERS AND THUNDERSTORMS COVER THE FLORIDA 
PANHANDLE FROM THE BIG BEND WESTWARD TO ALABAMA. SHOWERS AND 
THUNDERSTORMS ARE IN SOUTH FLORIDA NEAR LAKE OKEECHOBEE...AND
FROM CENTRAL FLORIDA NORTHEASTWARD...IN BROAD SURFACE LOW 
PRESSURE.

THE CARIBBEAN SEA...
UPPER LEVEL CYCLONIC FLOW COVERS THE AREA FROM 13N TO 24N 
BETWEEN 68W AND 78W. ISOLATED MODERATE SHOWERS COVER THE AREA 
FROM JAMAICA TO CUBA TO HISPANIOLA AND SURROUNDING WATERS.
UPPER LEVEL ANTICYCLONIC FLOW IS IN THE MIDDLE OF THE CYCLONIC 
FLOW JUST DESCRIBED...AND THE CYCLONIC FLOW IN THE SOUTHWESTERN 
GULF OF MEXICO...INTERIOR MEXICO...AND THE ADJACENT EASTERN 
PACIFIC OCEAN. AN INVERTED UPPER LEVEL TROUGH IS ALONG 65W
TO THE SOUTH OF 18N. SHOWERS AND THUNDERSTORMS ARE TO THE 
NORTHEAST OF THE LINE FROM 12N62W TO THE MONA PASSAGE WITH
THE 60W/61W TROPICAL WAVE.

THE ATLANTIC OCEAN...
A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 33N38W 
CYCLONIC CIRCULATION CENTER TO 25N45W 24N52W...ALONG A SHEAR 
AXIS TO A 24N63W CYCLONIC CENTER. ISOLATED MODERATE SHOWERS
TO THE NORTH OF 27N BETWEEN 46W AND 55W. A SURFACE TROUGH
PASSES THROUGH 31N60W TO 30N64W 28N70W 28N74W. SHOWERS ARE 
POSSIBLE WITHIN 60 NM ON EITHER SIDE OF THIS TROUGH.

$$
MT