000
AXNT20 KNHC 051207
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST MON MAR 05 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 
1145 UTC.

...THE ITCZ...

10N12W 6N20W 3N30W 1N40W...CROSSING THE EQUATOR AT 50W...INTO
NORTHEASTERN BRAZIL NEAR 1S54W. ISOLATED MODERATE SHOWERS TO 
LOCALLY STRONG THUNDERSTORMS WITHIN 180 TO 240 NM ON EITHER SIDE 
OF 6N10W 3N20W 1N32W...TO THE EQUATOR AT 51W. A SHIELD OF BROKEN 
TO OVERCAST HIGH CLOUDS IS SOUTH OF 10N61W 10N50W 16N40W 22N30W 
BEYOND 24N20W UNDER BROAD UPPER LEVEL ANTICYCLONIC WIND FLOW.

...DISCUSSION...

THE GULF OF MEXICO...
A DEEP LAYER TROUGH THAT STRETCHES FROM VIRGINIA/NORTH CAROLINA 
TO SOUTHERN GEORGIA...TO THE WESTERN GULF OF MEXICO NEAR 24N97W.
THIS TROUGH IS MOVING EASTWARD 10 TO 15 KT. MIDDLE TO UPPER 
LEVEL DRY AIR/SUBSIDENCE IS NORTH OF 24N BETWEEN NORTHERN 
FLORIDA AND THE TEXAS BIG BEND. A WEAK AND NOT WELL-DEFINED 
MIDDLE LEVEL CYCLONIC CIRCULATION CENTER IS OVER INTERIOR MEXICO 
NEAR 23N102W. ANOTHER NOT WELL-DEFINED MIDDLE LEVEL CYCLONIC 
CIRCULATION CENTER IS MOVING TOWARD THE GULF OF TEHUANTEPEC. 
MIDDLE TO UPPER LEVEL SOUTHWESTERLY WIND FLOW COVERS THE OPEN 
WATERS OF THE GULF OF MEXICO AWAY FROM THE ADVANCING DEEP LAYER 
TROUGH. A COLD FRONT GOES FROM JUST SOUTH OF ANDROS ISLAND IN 
THE BAHAMAS...ACROSS WESTERN CUBA TO 20N88W IN THE YUCATAN 
PENINSULA. A SURFACE TROUGH CONTINUES FROM 20N88W TO 17N90W
INTO NORTHERN GUATEMALA.

THE CARIBBEAN SEA...
A MIDDLE TO UPPER LEVEL TROUGH RUNS FROM THE SOUTHEASTERN CORNER 
OF THE AREA NEAR 12N62W TO 13N80W. EXTREMELY DRY AIR/SUBSIDENCE
COVERS THE AREA EAST OF 80W...AND EVEN INTO THE ATLANTIC WATERS 
FROM 10N TO 15N BETWEEN 55W AND 60W. A FRONTAL BOUNDARY NOW 
SKIRTING THE CARIBBEAN SEA FROM THE EDGES OF THE GULF OF 
MEXICO...IS FORECAST TO MOVE INTO THE AREA DURING THE NEXT
24 HOURS. IT ONLY WILL MOVE INTO THE NORTHWESTERN CORNER OF THE 
AREA AND THEN DISSIPATE BY 48 HOURS. EASTERLY SURFACE WIND 
SPEEDS OF 15 TO 20 KT ARE FORECAST GENERALLY SOUTH OF 15N...AND 
ALONG THE COLOMBIA COAST THROUGH 72 HOURS. SHOWERS ARE POSSIBLE 
IN CLUSTERS OF LOW TO MIDDLE LEVEL CLOUDS...EAST OF 77W...AND 
NORTHWEST OF 19N77W 12N82W.

THE ATLANTIC OCEAN...
AN UPPER LEVEL RIDGE IS ALONG 29N68W BEYOND 32N56W TO 33N35W
TO 38N20W. SOME OF THE UPPER LEVEL ANTICYCLONIC FLOW EVENTUALLY
REACHES THE CANARY ISLANDS. A MIDDLE TO UPPER LEVEL TROUGH 
EXTENDS FROM 25N26W TO 23N33W TO 14N47W 12N54W 12N62W...EVEN
EXTENDING MORE INTO THE WESTERN CARIBBEAN SEA TO 13N80W.
A SHIELD OF BROKEN TO OVERCAST HIGH CLOUDS IS SOUTH OF 10N61W 
10N50W 16N40W 22N30W BEYOND 24N20W UNDER BROAD UPPER LEVEL 
ANTICYCLONIC WIND FLOW. A COLD FRONT PASSES THROUGH 31N62W TO 
26N70W TO JUST SOUTH OF ANDROS ISLAND IN THE BAHAMAS TO WESTERN
CUBA. NO DEEP CONVECTIVE PRECIPITATION APPEARS TO BE NEAR THIS
FRONT. A SURFACE RIDGE EXTENDS FROM A 1028 MB HIGH PRESSURE
CENTER NEAR 35N19W TO 30N31W TO 26N47W 24N58W TO 25N65W.

$$
MT