Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 170608
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT WED SEP 17 2008

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS OFF THE COAST OF W AFRICA ALONG 18W S OF 19N 
MOVING W NEAR 10 KT. BROAD CYCLONIC TURNING IS OBSERVED E OF 
24W. ISOLATED MODERATE CONVECTION IS FROM 16N-20N BETWEEN 
15W-18W. 

A LOW AMPLITUDE TROPICAL WAVE IS ALONG 37W/38W SOUTH OF 13N 
MOVING W NEAR 10 KT. SCATTERED SHOWERS ARE PREDOMINATELY ALONG 
THE ITCZ FROM 4N-10N BETWEEN 32W-42W. 

A TROPICAL WAVE IS OVER THE LESSER ANTILLES ALONG 62W/63W S 
OF 21N MOVING W NEAR 10 KT. THE TOTAL PRECIPITABLE WATER 
PRODUCT FROM CIMMS DEPICTS ENHANCED DEEP LAYER MOISTURE JUST 
EAST OF THE WAVE AXIS. A SWIRL OF LOW CLOUDS IS LOCATED NEAR 
21N62W MOVING IN TANDEM WITH THIS TROPICAL WAVE. SCATTERED 
SHOWERS ARE WITHIN 200 NM E OF THE WAVE AXIS. 

A TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN SEA ALONG 79W S OF 
20N MOVING W 10-15 KT. THE WAVE IS GENERATING SCATTERED MODERATE 
TO ISOLATED STRONG CONVECTION ALONG THE COAST OF N COLOMBIA FROM 
10N-16N BETWEEN 71W-78W.  

A TROPICAL WAVE IS OVER CENTRAL AMERICA ALONG 90W S OF 21N 
MOVING W 10-15 KT. AN INVERTED-V STRUCTURE IS NOTED. CLUSTERS OF 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE WITHIN 120 
NM EITHER SIDE OF THE WAVE AXIS.  

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 10N15W 8N40W 10N62W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-11N BETWEEN 
21W-25W. SIMILAR CONVECTION IS ALSO SEEN WITHIN 100 NM N OF THE 
AXIS BETWEEN 46W-56W.  

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT EXTENDS FROM N FLORIDA TO THE BAY OF CAMPECHE ALONG 
30N82W 26N86W 24N93W 19N96W. SCATTERED SHOWERS ARE WITHIN 120 NM 
OF THE FRONT. SCATTERED MODERATE CONVECTION IS ALSO OVER THE BAY 
OF CAMPECHE FROM 17N-20N BETWEEN 94W-97W. 10-15 NLY WINDS ARE N 
OF THE FRONT. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS 
CENTERED OVER NE MEXICO NEAR 22N98W...WHICH DOMINATES THE W GULF 
W OF 90W. A TROUGH IS OVER THE E GULF AND FLORIDA E OF 90W.  
EXPECT... LIGHT CONVECTION ASSOCIATED WITH THE FRONT AS THE 
FRONT STALLS OVER THE GULF FOR THE NEXT 24 HOURS. ALSO...EXPECT 
AIRMASS CONVECTION OVER FLORIDA...WITH ADDITIONAL CONVECTION 
OVER THE BAY OF CAMPECHE AND THE YUCATAN PENINSULA.

CARIBBEAN SEA...
THREE TROPICAL WAVES ARE OVER THE CARIBBEAN SEA AND CENTRAL 
AMERICA. SEE ABOVE. FRESH SURFACE EASTERLIES DOMINATE MUCH OF 
THE REMAINDER OF THE CARIBBEAN. SCATTERED SHOWERS PERSIST OVER 
HISPANIOLA AND THE CENTRAL CARIBBEAN N OF 15N. IN THE UPPER 
LEVELS...AN UPPER LEVEL HIGH IS OVER THE W CARIBBEAN SEA NEAR 
17N84W.  AN UPPER LEVEL LOW IS CENTERED OVER THE LEEWARD ISLANDS 
NEAR 17N66W. SIGNIFICANT MOISTURE DOMINATES THE ENTIRE 
CARIBBEAN. EXPECT CONVECTION ASSOCIATED WITH THE TROPICAL WAVES 
OVER THE NEXT 24 HOURS. ALSO EXPECT AIRMASS CONVECTION OVER 
CENTRAL AMERICA.

ATLANTIC OCEAN...
TWO TROPICAL WAVES ARE OVER THE ATLANTIC OCEAN. SEE ABOVE. A 
SURFACE TROUGH IS OVER THE W ATLANTIC ALONG 32N61W 23N72W.  
SCATTERED MODERATE CONVECTION IS FROM 26N-28N BETWEEN 57W-60W. 
SCATTERED SHOWERS ARE ALSO WITHIN 120 NM OF THE TROUGH AXIS. A 
1027 MB SURFACE HIGH IS OVER THE CENTRAL ATLANTIC NEAR 34N41W. A 
SURFACE RIDGE EXTENDS SW FROM THE HIGH TO 25N60W. IN THE UPPER 
LEVELS...THREE UPPER LEVEL LOWS ARE OVER THE CENTRAL ATLANTIC AT 
31N63W...30N55W...AND AT 25N42W. A LARGE TROUGH IS OVER THE E 
ATLANTIC N OF 20N AND E OF 30W. A LARGE UPPER LEVEL HIGH IS 
CENTERED OVER THE TROPICAL ATLANTIC NEAR 16N46W. EXPECT THE 
TROPICAL WAVES TO PROPAGATE WEST WITH SCATTERED SHOWERS OVER THE 
NEXT 24 HOURS.

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FORMOSA