000
AXNT20 KNHC 260454
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT THU JUL 26 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 
SECTIONS OF SOUTH AMERICA...AND THE 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 
0415 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 28W S OF 18N MOVING W 10-15 KT. LOW 
AMPLITUDE LOW LEVEL INVERTED-V SIGNATURE IS OBSERVED COVERING 
THE AREA FROM 23W-31W. SMALL CLUSTERS OF SCATTERED MODERATE/ 
ISOLATED STRONG CONVECTION ARE EMBEDDED WITHIN THE ITCZ FROM 
12N-15W BETWEEN 25W-30W.  

TROPICAL WAVE IS ALONG 42W S OF 15N MOVING W NEAR 20 KT. VERY 
LOW AMPLITUDE LOW LEVEL INVERTED-V SIGNATURE IS OBSERVED 
COVERING THE AREA FROM 39W-45W. SMALL CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 60 NM OF LINE 
FROM 12N42W TO 11N46W. 

TROPICAL WAVE IS ALONG 65W/66W S OF 15N MOVING W NEAR 25 KT. 
WAVE HAS WEAKENED OVER THE PAST 24 HOURS AS IT ENTERED THE 
CARIBBEAN WITH SHALLOW LOW LEVEL INVERTED-V SIGNATURE COVERING 
THE AREA FROM 65W-72W. NO ASSOCIATED DEEP CONVECTION WITH 
ISOLATED SHOWERS FROM 13N-15N BETWEEN 66W-71W.

TROPICAL WAVE IS ALONG 90W S OF 25N MOVING W 15-20 KT. ANY 
SATELLITE SIGNATURE IS MASKED BY A LARGE UPPER HIGH CENTERED 
OVER THE YUCATAN CHANNEL. ANY CONVECTION ASSOCIATED WITH THIS 
WAVE IS INLAND OVER CENTRAL AMERICA/MEXICO AND IN THE E PACIFIC 
REGION. 

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 15N15W 13N20W 14N26W 11N34W 10N41W 
8N45W 9N61W. ANY CONVECTION FOUND IS ASSOCIATED WITH THE 
TROPICAL WAVES. SEE ABOVE. 

...DISCUSSION...
GULF OF MEXICO...
LARGE UPPER HIGH OVER THE YUCATAN CHANNEL DOMINATES THE GULF 
GENERATING ISOLATED SHOWERS WITH WIDELY ISOLATED THUNDERSTORMS 
DOTTING ENTIRE AREA WITH THE HIGHEST CONCENTRATION OF SHOWERS S 
OF 25N TO OVER CUBA FROM 82W-85W. 

CARIBBEAN SEA...
LARGE UPPER HIGH IS OVER THE YUCATAN CHANNEL DOMINATING THE AREA 
W OF 75W AND EXTENDING OVER THE GULF OF MEXICO AND THE SW ATLC 
AND GENERATING CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION FROM 14N-22N BETWEEN 77W-83W. UPPER RIDGE EXTENDING 
FROM THE CENTRAL ATLC COVERS THE REMAINDER OF THE CARIBBEAN 
CREATING A WEAK UPPER LEVEL INVERTED TROUGH EXTENDING FROM 
PANAMA TO THE MONA PASSAGE WITH DRY STABLE AIR COVERING THE E 
CARIBBEAN E OF 77W. THE ITCZ AXIS EXTENDS FROM ACROSS COLOMBIA/ 
PANAMA AND COSTA RICA INTO THE E PACIFIC REGION GENERATING 
CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N TO 
INLAND OVER PANAMA BETWEEN COLOMBIA AND 80W. 

ATLANTIC OCEAN...
LARGE UPPER HIGH OVER THE YUCATAN CHANNEL EXTENDS A OVER THE SW 
ATLC WITH AN ADDITIONAL RIDGE AXIS EXTENDING FROM THE CENTRAL 
BAHAMAS NE TO JUST E OF BERMUDA NEAR 32N68W GENERATING SMALL 
CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 
24N-29N BETWEEN 68W-80W. LARGE UPPER LOW IN THE W/CENTRAL ATLC 
IS CENTERED NEAR 31N57W COVERING THE AREA N OF 22N FROM 46W-63W 
SMALL CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 
27N BETWEEN 51W-58W. BENIGN UPPER LEVEL RIDGE/TROUGH/RIDGE WITH 
DRY STABLE AIR AND A STRONG SURFACE RIDGE DOMINATE THE REMAINDER 
OF THE ATLC WITH THE SURFACE RIDGE ANCHORED BY A 1028 MB HIGH 
WELL N OF THE REGION PRODUCING ONLY FAIR WEATHER CLOUDS ACROSS 
THE REMAINDER OF THE AREA. 

$$
WALLACE