000
AXNT20 KNHC 291048
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SUN JUL 29 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

...SPECIAL FEATURE...
SURFACE TROUGH IS LOCATED FROM 29N71W TO 23N74W. ENVIRONMENTAL 
CONDITIONS ARE FORECAST TO BECOME MORE FAVORABLE FOR TROPICAL 
CYCLONE DEVELOPMENT AS THE SYSTEM MOVES NNE OVER THE NEXT DAY OR 
TWO. SCATTERED SHOWERS AND TSTMS ARE LOCATED FROM 25N-30N E OF 
TROUGH TO 70W.

...TROPICAL WAVES...
TROPICAL WAVE OVER THE E ATLC FROM 4N-18N ALONG 24W MOVING W 
10-15 KT. CONVECTION IS CONFINED TO THE AREA ALONG THE ITCZ.    

TROPICAL WAVE FROM 5N-18N ALONG 44W MOVING W 10 KT. MODERATE TO 
ISOLATED STRONG CONVECTION FROM 6N-10N BETWEEN 43W-47W.

TROPICAL WAVE S OF 19N ALONG 59W MOVING W 10-15 KT. NO 
CONVECTION ASSOCIATED WITH THE WAVE.

TROPICAL WAVE LOCATED OVER THE FAR WESTERN CARIBBEAN S OF 19N 
ALONG 88W MOVING W 10 KT. NO CONVECTION OVER THE CARIBBEAN BUT 
STRONG THUNDERSTORMS OVER THE PACIFIC COAST OF HONDURAS.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 11N15W 10N20W 9N35W 10N45W 11N61W. 
SCATTERED MODERATE CONVECTION IS WITHIN 60 NM EITHER SIDE OF 
AXIS FROM 15W-18W. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
WITHIN 30 NM EITHER SIDE OF AXIS FROM 35W-37W.

...DISCUSSION...
GULF OF MEXICO
UPPER LEVEL RIDGE EXTENDS FROM CENTRAL MEXICO INTO THE NW GULF 
OF MEXICO TO LOUISIANA IS NEARLY STATIONARY. ANTICYCLONIC FLOW 
COVES MUCH OF THE GULF OF MEXICO. THERE AREA FEW SHOWERS OVER 
THE CENTRAL GULF NEAR 25N90W OTHERWISE ONLY MID TO UPPER LEVEL 
DEBRIS CLOUDS LEFT OVER FROM PREVIOUS CONVECTION ACROSS THE AREA.

CARIBBEAN
AN INVERTED UPPER LEVEL TROUGH WITH AXIS FROM THE NICARAGUA NE 
ACROSS JAMAICA TO THE WINDWARD PASSAGE. ONLY ISOLATED SHOWERS 
ALONG THE S COAST OF CUBA AND THE SW CARIBBEAN. AN ANTICYCLONIC 
CIRCULATION IS CENTERED OVER THE CENTRAL CARIBBEAN NEAR 14N75W 
WITH ANOTHER TROUGH E OF ANTICYCLONE IN THE EASTERN CARIBBEAN. 
DRY STABLE AIR WITH MID/UPPER LEVEL SUBSIDENCE COVERS THE E 
CARIBBEAN...HOWEVER A FEW SHOWERS ARE MOVING INTO THE WINDWARD 
ISLANDS WITH AN APPROACHING TROPICAL WAVE.

ATLANTIC
DEEP LAYER TROUGH EXTENDS FROM 31N73W ACROSS THE NORTHERN 
BAHAMAS TO 23N78W. DOWNSTREAM RIDGE FROM WEAK ANTICYCLONE NEAR 
24N66W TO 31N66W. DIFFLUENCE ALOFT BETWEEN THE TROUGH AND 
ANTICYCLONE IS ENHANCING CONVECTIVE ACTIVITY ASSOCIATED WITH 
TROUGH DISCUSSED IN SPECIAL FEATURES SECTION. A WELL-DEFINED 
ELONGATED MIDDLE/UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED 
NEAR 33N63W AND IS DRIFTING NE. TROUGH EXTENDS SOUTHWARD FROM 
THE CIRCULATION TO NEAR 25N58W. BROAD RIDGING ALOFT COVERS MOST 
OF THE EASTERN ATLC WITH MODERATE TO STRONG SUBSIDENCE AND DRY 
STABLE AIR N OF THE ITCZ. AN UPPER LEVEL TROUGH EMBEDDED IN THE 
RIDGE EXTENDS FROM 31N37W TO 26N42W.

$$
DGS