000
AXNT20 KNHC 180605 RRA
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT WED APR 18 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0345 UTC.

...THE ITCZ...
5N8W 4N20W...CROSSING THE EQUATOR AT 30W...TO 5S40W IN 
NORTHEASTERN BRAZIL. ISOLATED MODERATE SHOWERS AND POSSIBLE
THUNDERSTORMS ARE SOUTH OF 10N EAST OF 35W...AND SOUTH OF
2N BETWEEN 30W AND 40W.

...DISCUSSION...

THE GULF OF MEXICO...
GRADUAL AND EVER-SO-SLIGHT UPPER LEVEL ANTICYCLONIC WIND FLOW 
COVERS THE GULF WATERS IN THE WAKE OF THE MIDDLE TO UPPER LEVEL
TROUGH THAT NOW IS MOVING FROM EAST TEXAS TO ARKANSAS AND 
LOUISIANA. THE SURFACE TROUGH/FRONT SYSTEM IS IN CENTRAL TEXAS.
BROAD SURFACE LOW PRESSURE COVERS MEXICO AND THE GULF OF MEXICO
BETWEEN 90W AND THE EAST COAST OF MEXICO.

THE CARIBBEAN SEA...
MIDDLE TO UPPER LEVEL DRY AIR ALREADY IS IN PLACE IN THE 
CARIBBEAN SEA. BROAD UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS 
THE AREA. MIDDLE LEVEL VARIABLE-DIRECTION WINDS ARE REPORTED
ON THE CIMSS SATELLITE DERIVED WINDOW FROM 18/0600 UTC. 
ANTICYCLONIC WIND FLOW COVERS THE ENTIRE AREA. MIDDLE TO UPPER 
LEVEL DRY AIR/SUBSIDENCE IS EVERYWHERE. THE SOUTHERNMOST POINT 
OF THE ATLANTIC OCEAN COLD FRONT REACHES 20N67W TO 18N71W.

THE ATLANTIC OCEAN...
DEEP LAYER CYCLONIC FLOW COVERS THE AREA NORTH OF 20N WEST OF 50W
WITH THE DEEP LAYER CYCLONIC CIRCULATION CENTER AND TROUGH THAT
HAVE BEEN BRINGING STORMY WEATHER FROM MAINLAND U.S.A. INTO THE 
ATLANTIC OCEAN. THE WESTERN ATLANTIC CYCLONIC CENTER AND TROUGH
ARE SUPPORTING THE COLD FRONT THAT PASSES THROUGH 32N53W TO 
24N60W TO 19N70W IN THE DOMINICAN REPUBLIC. ISOLATED MODERATE 
SHOWERS AND POSSIBLE THUNDERSTORMS ARE WITHIN 30 TO 60 NM ON 
EITHER SIDE OF 22N59W 28N52W...AND NORTH OF 27N BETWEEN 43W AND 
52W. BROKEN TO OVERCAST LOW TO MIDDLE LEVEL CLOUDS AND POSSIBLE
PRECIPITATION ARE WITHIN 60 TO 90 NM ON EITHER SIDE OF 23N58W
20N63W...AND FROM PUERTO RICO WESTWARD FROM 20N63W TO 18N66W
TO 18N72W. THE DEEP LAYER CYCLONIC CIRCULATION CENTER AND TROUGH 
FROM 24 HOURS AGO HAVE MOVED EASTWARD QUITE A BIT AND NOW ARE IN 
NORTHERN AFRICA. AN UPPER LEVEL TROUGH IS IN THE TROPICAL JET 
STREAM. BROAD WESTERLY FLOW FROM VENEZUELA AND GUYANA/SURINAME/
AND FRENCH GUIANA TO 1N47W...AND THEN NORTHEASTWARD...BEYOND 
23N24W. MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE IS WITHIN
500 TO 600 NM NORTH AND WEST OF THE JET STREAM.

$$
MT