000
AXNT20 KNHC 031043
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE APR 3 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 
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 
1015 UTC.

...THE ITCZ...
ITCZ AXIS EXTENDS FROM AFRICA NEAR 7N10W 4N19W 1N36W 2N52W.  
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 75 NM OF 
LINE 2N19W ACROSS THE ITCZ AXIS TO 7N16W. CLUSTERS OF SIMILAR 
CONVECTION ARE FROM THE EQUATOR TO 5N BETWEEN 30W-35W. 

...DISCUSSION...

GULF OF MEXICO...
BROAD UPPER RIDGE CONTINUES TO DOMINATE THE GULF INTO THE W 
ATLC WITH THE AXIS EXTENDING THROUGH THE YUCATAN CHANNEL TO OVER 
THE SE US. THIS IS ADVECTING UPPER LEVEL MOISTURE FROM THE E 
PACIFIC ACROSS MEXICO INTO THE W/CENTRAL GULF GENERATING 
SCATTERED SHOWERS/POSSIBLE ISOLATED THUNDERSTORMS ALONG THE 
TEXAS/LOUISIANA COASTLINE. A SURFACE RIDGE EXTENDS FROM THE W 
ATLC INTO THE GULF PRODUCING LIGHT S TO E WINDS ACROSS THE 
ENTIRE GULF. BROKEN/OVERCAST HIGH CLOUDS COVER MOST OF THE 
W/CENTRAL GULF WHILE THE SE GULF HAS RELATIVELY CLEAR SKIES. 

CARIBBEAN SEA...
BROAD UPPER E/W RIDGE EXTENDS ACROSS THE N PORTION OF SOUTH 
AMERICA COVERING THE CARIBBEAN WITH MOSTLY SW TO W UPPER WINDS 
ADVECTING TROPICAL MOISTURE ACROSS THE SW GULF. MODERATE/STRONG 
SUBSIDENCE AND DRY UPPER AIR COVER THE N CARIBBEAN N OF 14N E OF 
80W. THE SURFACE RIDGE FROM THE W ATLC CONTINUES TO WEAKEN. 
HOWEVER...THE EASTERLY TRADE WINDS REMAIN MODERATE TO STRONG 
ACROSS THE AREA. THESE WINDS ARE BRINGING IN LOW LEVEL MOISTURE 
ACROSS THE AREA FROM 12N-15N E OF 77W ACROSS THE LESSER 
ANTILLES. 

ATLANTIC OCEAN...
BROAD UPPER RIDGE THAT COVERS THE CARIBBEAN AND GULF OF MEXICO 
EXTEND INTO THE W ATLC W OF 60W. A SURFACE RIDGE COVERS THE W 
ATLC W OF 50W INTO THE GULF OF MEXICO ANCHORED BY A 1023 MB HIGH 
SW OF BERMUDA NEAR 29N71W. A DEEP LAYERED TROUGH IS IN THE 
E/CENTRAL ATLC N OF 20N FROM 25W-60W WITH THE UPPER LOW WELL N 
OF THE REGION. THE ASSOCIATED COLD FRONT ENTERS THE REGION NEAR 
32N27W EXTENDING SSW TO 20N37W DISSIPATING TO NEAR 17N41W AND A 
WEAKENING SECOND SURGE COLD FRONT IS JUST NORTH OF THE AREA. LOW 
LEVEL CLOUDS WITH ISOLATED SHOWERS ARE WITHIN 100 NM OF THE 
FRONTAL BOUNDARY. A SURFACE LOW CENTERED IN THE NW ATLC NEAR 
37N63W IS EXPECTED TO DEEPEN AND DROP SE INTO THE N PORTION OF 
THE CENTRAL ATLC OVER THE NEXT 24 HOURS INCREASING SHOWER 
ACTIVITY WITH ASSOCIATED STRONGER WINDS AND HIGH SEAS TO WELL 
WITHIN THE AREA. MODERATE/STRONG SUBSIDENCE AND DRY UPPER AIR 
COVER THE AREA WITHIN 300/350 NM OF LINE FROM THE LEEWARD 
ISLANDS NEAR 17N61.5W TO 21N41W THEN NARROWING TO WITHIN 200 NM 
ALONG 23N34W TO AFRICA NEAR 26N14W. BROAD E/W UPPER RIDGE COVERS 
THE TROPICAL ATLC EXTENDING FROM AFRICA ACROSS THE ATLC TO SOUTH 
AMERICA WITH THE AXIS ROUGHLY ALONG 6N/7N THUS SUPPRESSING THE 
ITCZ AXIS TO THE S. 

$$
WADDINGTON/WALLACE