000
AXNT20 KNHC 291029
TWDAT 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT MAR 29 2008

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.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 5N9W 3N18W 4N30W CROSSING THE 
EQUATOR NEAR 43W TO 1S49W. A SURFACE TROUGH FORMS A SOUTHERN 
ITCZ EXTENDING FROM 1N13W TO S OF THE EQUATOR NEAR 16W AND INTO 
BRAZIL SOUTH AMERICA. SCATTERED MODERATE/STRONG CONVECTION IS 
WITHIN 150 NM N OF THE ITCZ AXIS FROM 40W-48W. CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 90 NM 
OF THE ITCZ AXIS FROM 9W-18W...FROM 19W-31W...WITHIN 90 NM OF 
THE SURFACE TROUGH TO S OF THE EQUATOR...AND FROM 4N TO S OF THE 
EQUATOR BETWEEN 33W-40W. 

...DISCUSSION...

GULF OF MEXICO...
BROAD UPPER RIDGE ANCHORED IN THE E PACIFIC REGION COVERS MEXICO 
AND THE GULF W OF 85W ADVECTING UPPER MOISTURE ACROSS THE AREA N 
OF 23N W OF 87W BRINGING SCATTERED SHOWERS OVER THE NW GULF N OF 
24N W OF 90W TO INLAND OVER E TEXAS AND LOUISIANA. AN INDUCED 
UPPER TROUGH IS MOVING ACROSS THE FAR SE US AND THE E GULF AND 
INTO THE W ATLC BY THE UPPER RIDGE ABOVE AND AN UPPER RIDGE OVER 
THE W ATLC BUT IS NOT PRODUCING ANY SURFACE FEATURES. SURFACE 
RIDGE REMAINS OVER THE E GULF BUT IS BEGINNING TO WEAKEN WITH A 
1020 MB HIGH ALONG THE COAST OF FLORIDA NEAR CEDAR KEY. THIS 
CONTINUES TO GIVE THE ENTIRE GULF SOUTHERLY RETURN FLOW WITH 
SOME BANKING OF LOW CLOUDS ALONG THE COAST OF TEXAS AND MEXICO W 
OF 96W. THE REMAINDER OF THE GULF IS UNDER MOSTLY CLEAR SKIES 
THIS MORNING. 

CARIBBEAN SEA...
THE INDUCED UPPER TROUGH OVER THE FAR E GULF OF MEXICO DIPS S 
INTO THE NW CARIBBEAN N OF 17N BETWEEN 78W-85W. THE REMAINDER OF 
THE CARIBBEAN IS DOMINATED BY A BROAD UPPER RIDGE ANCHORED OVER 
SOUTH AMERICA AND EXTENDS INTO THE W TROPICAL ATLC AND THE 
CENTRAL ATLC. MODERATE/STRONG EASTERLY TRADE WINDS DOMINATES THE 
ENTIRE CARIBBEAN. SCATTERED SHOWERS ARE N OF 17W TO OVER 
HISPANIOLA AND JAMAICA. ISOLATED SHOWERS ARE BEING USHERED IN 
WITH THE TRADE WINDS AND DOT THE E CARIBBEAN E OF 67W TO OVER 
THE LESSER ANTILLES. 

ATLANTIC OCEAN...
THE INDUCED UPPER TROUGH OVER THE FAR E GULF OF MEXICO EXTENDS 
ACROSS THE FLORIDA PENINSULA AND INTO THE W ATLC W OF 82W. THE 
REMAINDER OF THE W ATLC AND INTO THE CENTRAL ATLC IS DOMINATED 
BY THE UPPER RIDGE THAT IS INDUCING THE UPPER TROUGH OVER THE E 
GULF OF MEXICO AND NW CARIBBEAN. A WEAK SURFACE TROUGH IS 
BENEATH THE UPPER RIDGE EXTENDING FROM 30N75W TO THE N BAHAMA 
ISLANDS NEAR 26N77W AND IS PRODUCING ISOLATED SHOWERS FROM 
27N-30N BETWEEN 74W-78W. THE UPPER RIDGE THAT COVERS THE 
CARIBBEAN EXTENDS AN AXIS FROM INLAND OVER SOUTH AMERICA INTO 
THE W TROPICAL ATLC NEAR 8N60W NE INTO CENTRAL ATLC TO 30N40W. A 
SURFACE TROUGH...REMNANTS OF A FRONTAL BOUNDARY...EXTENDS FROM 
25N70W ACROSS THE TURKS AND CAICOS TO THE E TIP OF CUBA. THE E 
THE ATLC IS DOMINATED BY AN UPPER TROUGH THAT EXTENDS THROUGH 
32N15W SW TO 24N26W WITH A HIGH AMPLITUDE RIDGE AXIS COVERING 
THE REMAINDER OF THE E ATLC E OF THE CAPE VERDE ISLANDS TO THE 
CANARY ISLANDS AND INLAND OVER W AFRICA. A BROAD SURFACE RIDGE 
COVERS THE ENTIRE ATLC INTO THE E GULF OF MEXICO WITH A WEAKNESS 
IN THE IMMEDIATE VICINITY OF THE SURFACE TROUGHS AND ANCHORED BY 
A 1028 AND 1027 MB HIGHS N OF THE REGION. 

$$
WALLACE