000
AXNT20 KNHC 031757
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT FRI JUL 03 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 LARGE TROPICAL WAVE IS ALONG 39W S OF 18N MOVING W NEAR 20 KT. 
THIS WAVE COINCIDES WITH A HIGH AMPLITUDE DEEP LAYER MOISTURE 
MAXIMUM OBSERVED ON TOTAL PRECIPITABLE WATER IMAGERY. SATELLITE 
IMAGERY INDICATES AN INVERTED-V LOW CLOUD BAND ALONG THE WAVE 
AXIS WITH A RELATED BROAD LOW-LEVEL CYCLONIC CIRCULATION FURTHER 
W NEAR 13N45W. ISOLATED MODERATE CONVECTION IS MOSTLY CONFINED 
TO THE ITCZ FROM 4N-9N BETWEEN 36W-42W.

A TROPICAL WAVE IS ALONG 59W S OF 17N MOVING W 15-20 KT. THIS 
WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM OBSERVED ON 
TOTAL PRECIPITABLE WATER IMAGERY. A LARGE AREA OF SCATTERED 
MODERATE CONVECTION IS OVER THE WINDWARD ISLANDS FROM 10N-14N 
BETWEEN 58W-65W. THIS CONVECTION IS BEING ENHANCED BY UPPER 
LEVEL DIFFLUENCE AROUND AN UPPER LEVEL LOW IN THE ERN CARIBBEAN 
NEAR 14N66W 

A TROPICAL WAVE IS ALONG 79W S OF 17N MOVING W 15-20 KT. 
POSITION IS BASED ON CONTINUITY. SCATTERED MODERATE TO STRONG 
CONVECTION IS W OF THE WAVE AXIS FROM 8N-12N BETWEEN 80W-84W. 
THIS ACTIVITY IS MOST LIKELY BEING ENHANCED BY DIFFLUENCE FROM 
AN UPPER LEVEL LOW CENTERED OVER THE NW CARIBBEAN NEAR 19N84W.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 10N14W 7N30W 9N39W 6N50W AND TO 
THE NE COAST OF S AMERICA NEAR 7N60W. SCATTERED MODERATE 
CONVECTION IS ALONG THE COAST OF AFRICA FROM 8N-12N BETWEEN 
14W-20W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 7N-9N 
BETWEEN 20W-26W...FROM 5N-7N BETWEEN 32W-34W...AND FROM 6N-9N 
BETWEEN 42W-47W.  

...DISCUSSION...

GULF OF MEXICO...
AS OF 1500 UTC...A COLD FRONT IS OVER THE FLORIDA PANHANDLE 
ALONG 31N84W 30N88W. ISOLATED MODERATE CONVECTION IS WITHIN 30 
NM OF THE FRONT. A 1020 MB HIGH IS CENTERED OVER THE SE GULF OF 
MEXICO NEAR 24N83W. A BAND OF SHOWERS AND THUNDERSTORMS ARE N OF 
THE HIGH FROM 25N-27N BETWEEN 82W-90W. 5-10 KT SOUTHERLY SURFACE 
WINDS ARE OVER THE W GULF W OF 90W. IN THE UPPER LEVELS...AN 
UPPER LEVEL LOW IS OVER THE W GULF NEAR 26N95W MOVING SW. 
SCATTERED SHOWERS ARE FROM 25N-27N BETWEEN 93W-96W. AN UPPER 
LEVEL TROUGH IS OVER N FLORIDA N OF 27N SUPPORTING THE COLD 
FRONT. EXPECT...THE COLD FRONT TO DRIFT E OVER THE NEXT 24 HOURS 
WITH CONVECTION. ALSO EXPECT THE SURFACE HIGH TO DRIFT W TO THE 
CENTRAL GULF WITH SHOWERS POSSIBLE S OF 25N.     

CARIBBEAN SEA...
TWO TROPICAL WAVES ARE PRODUCING CONVECTION OVER THE CARIBBEAN. 
SEE ABOVE. ELSEWHERE...ISOLATED MODERATE CONVECTION IS OVER 
BELIZE. NEAR GALE FORCE WINDS ARE ALONG THE COAST OF N COLOMBIA. 
FRESH TO STRONG TRADEWINDS ARE OVER THE REMAINDER OF THE SEA. 
EXPECT...THE TROPICAL WAVES TO MOVE QUICKLY W OVER THE NEXT 24 
HOURS WITH CONVECTION.     

ATLANTIC OCEAN...
A 1024 MB HIGH IS OVER THE W ATLANTIC NEAR 27N61W. A 1013 MB LOW 
IS OVER THE CENTRAL ATLANTIC NEAR 32N43W. A SURFACE TROUGH 
EXTENDS S FROM THE LOW TO 26N46W. SCATTERED MODERATE CONVECTION 
IS FROM 31N-33N BETWEEN 39W-42W. A 1026 MB HIGH IS OVER THE E 
ATLANTIC NEAR 32N25W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH 
IS OVER THE W ATLANTIC NEAR 30N60W. AN UPPER LEVEL LOW IS OVER 
THE CENTRAL ATLANTIC NEAR 30N40W. EXPECT THE SURFACE LOW TO MOVE 
E TO NEAR 32N38W IN 24 HOURS WITH CONVECTION. 

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FORMOSA