000
AXNT20 KNHC 231022
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU AUG 23 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 
0945 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 41W/42W S OF 13N MOVING 15-20 KT. LOW 
AMPLITUDE WAVE WITH WEAK INVERTED-V CURVATURE. NO ASSOCIATED 
DEEP CONVECTION. 

TROPICAL WAVE IS ALONG 63W S OF 22N MOVING W 15-20 KT. WAVE HAS 
A WELL DEFINED INVERTED-V CURVATURE ESPECIALLY N OF 16N. 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120 NM OF 
LINE FROM 21N61W ACROSS THE LEEWARD/VIRGIN ISLANDS TO THE ABC 
ISLANDS AND THE COAST OF SOUTH AMERICA NEAR 10N67W. 

TROPICAL WAVE IS FROM 29N76W ACROSS THE N BAHAMAS AND CUBA NEAR 
22N79W TO JUST OFF PANAMA NEAR 10N80W MOVING W 15-20 KT. VERY 
BROAD HIGH AMPLITUDE WAVE WITH A WELL DEFINED INVERTED-V 
CURVATURE AND A SMALL LOW LEVEL ROTATION NEAR THE BAHAMA ISLANDS 
IN THE W ATLC. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS 
WITHIN 90/120 NM OF LINE FROM 19N76W TO 15N82W INCLUDING 
JAMAICA. 

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 12N15W 8N27W 10N50W 9N61W. CLUSTERS 
OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 75 
NM OF THE AXIS W OF 48W TO INLAND OVER SOUTH AMERICA. CLUSTERS 
OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM OF THE AXIS 
FROM 29W-37W. 
 
DISCUSSION...

GULF OF MEXICO...
AN UPPER RIDGE EXTENDS FROM CENTRAL AMERICA ACROSS S MEXICO INTO 
THE BAY OF CAMPECHE NEAR 19N94W TO NEAR TAMPICO MEXICO ENHANCING 
SCATTERED SHOWERS/THUNDERSTORMS S OF 22N W OF 95W TO INLAND OVER 
MEXICO. THE REMAINDER OF THE GULF IS UNDER EASTERLY UPPER LEVEL 
WINDS IN RESPONSE TO THE UPPER LOW IN THE N CARIBBEAN GENERATING 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS IN THE E GULF WITHIN 75 
NM OF LINE FROM NEAR FORT MYERS FLORIDA ALONG 25N86W THROUGH THE 
YUCATAN CHANNEL. OTHERWISE...THE GULF REMAINS CLEAR THIS 
MORNING. 

CARIBBEAN SEA...
AN UPPER LOW DOMINATES THE W CARIBBEAN CENTERED BETWEEN THE 
CAYMAN ISLANDS AND CUBA NEAR 20N82W EXTENDING AN UPPER TROUGH NE 
INTO THE W ATLC WITH A WEAKER UPPER TROUGH EXTENDING TO OVER 
CENTRAL AMERICA GENERATING SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS N OF 19N THROUGH THE YUCATAN CHANNEL BETWEEN 
83W-87W AND ENHANCING CONVECTION ASSOCIATED WITH THE TROPICAL 
WAVE. A WEAK UPPER HIGH IS JUST S OF HAITI GIVING THE REMAINDER 
OF THE CARIBBEAN EASTERLY UPPER FLOW CLEARING THE CARIBBEAN WITH 
THE EXCEPTION OF THE ACTIVITY ASSOCIATED WITH THE TROPICAL 
WAVES. 
   
ATLANTIC OCEAN...
BROAD UPPER TROUGH EXTENDS FROM THE UPPER LOW IN THE NW 
CARIBBEAN ACROSS CUBA NEAR 22N80W TO 29N76W COVERING THE W ATLC 
AND GENERATING SOME ISOLATED SHOWERS FROM 25N-30N BETWEEN 
76W-80W. A TROPICAL WAVE IS BENEATH THIS UPPER TROUGH. AN UPPER 
RIDGE EXTENDS FROM THE UPPER HIGH JUST S OF HAITI NE TO 26N69W 
ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 20N-25N 
BETWEEN 67W-70W. A BENIGN UPPER LOW/HIGH/LOW ARE OVER THE 
CENTRAL ATLC WHILE A TYPICAL UPPER RIDGING EXTENDS E FROM AFRICA 
OUT TO 30W. LARGE BUT SOMEWHAT WEAKER SURFACE RIDGE REMAINS IN 
CONTROL OF THE ATLC TO ACROSS THE SE US AND N GULF OF MEXICO 
WITH A WEAK 1021 MB HIGH LOCATED NEAR 28N55W. ALL OF THIS IS 
PRODUCING ABUNDANCE OF DRY STABLE CONDITIONS ACROSS THE ATLC 
WITH THE EXCEPTION OF THE AREA ASSOCIATED WITH THE TROPICAL 
WAVES.
  
$$
WALLACE