000
AXNT20 KNHC 071304
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI APR 07 2006

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...WEATHER OBSERVATIONS... 
RADAR...AND METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1045 UTC.

...THE ITCZ...

ITCZ 9N11W 5N20W 3N26W 3N36W TO THE EQUATOR AT 51W. SCATTERED TO 
NUMEROUS STRONG SHOWERS AND THUNDERSTORMS WITHIN 60 NM ON EITHER 
SIDE OF 8N14W 5N20W 3N25W 4N27W...AND WITHIN A 15 NM TO 30 NM 
RADIUS OF 2N17W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG 
THUNDERSTORMS ARE FOUND ELSEWHERE FROM FROM 4S TO 4N BETWEEN
30W AND 50W.

...DISCUSSION...

THE GULF OF MEXICO...
A SURFACE RIDGE EXTENDS FROM A BERMUDA 1021 MB HIGH PRESSURE
CENTER TO SOUTH FLORIDA AND THE SOUTH CENTRAL GULF WATERS.
UPPER LEVEL ANTICYCLONIC FLOW COVERS THE GULF WATERS. THIS
ANTICYCLONIC FLOW IS COURTESY OF AN UPPER LEVEL RIDGE WHICH
NOW RUNS FROM SOUTH CAROLINA AND GEORGIA TO THE SOUTHEASTERN 
GULF. A FRONTAL BOUNDARY RUNS FROM SOUTH CENTRAL TEXAS 
NORTHWARD. THIS FRONT IS FORECAST TO REACH THE TEXAS GULF COAST
ON FRIDAY NIGHT. A DEEP LAYER TROUGH IS MOVING THROUGH THE 
MIDDLE OF THE U.S.A. THIS NEXT FRONT IS FORECAST NOT TO BRING
A SIGNIFICANT AMOUNT OF MOISTURE WITH IT. IT IS POSSIBLE THAT
ONLY PARTS OF THE WESTERN GULF WILL EXPERIENCE ANY RAINFALL
WITH THIS FRONT.

THE CARIBBEAN SEA...
UPPER LEVEL SOUTHWESTERLY WIND FLOW IN A JET STREAM STRETCHES
FROM COLOMBIA AND VENEZUELA NORTHEASTWARD...CROSSING THE 
CARIBBEAN WATERS AND EXITING ON TOP OF THE EASTERN AND 
NORTHEASTERN ISLANDS OF THE AREA. BROKEN TO OVERCAST MULTILAYERED
CLOUDS ARE WITHIN AT LEAST 250 NM ON EITHER SIDE OF THE LINE 
10N69W 15N61W BEYOND 20N55W. THE WIND SPEEDS OF THE JET STREAM
IN THIS CLOUDINESS...ACCORDING TO THE 07/0900 UTC CIMSS 
SATELLITE DERIVED WIND DATA...RANGE FROM 50 KT ALONG THE EASTERN
PERIPHERY OF THE CLOUDS TO 100 KT ALONG THE WESTERN PERIPHERY
OF THE CLOUDS. THE MAXIMUM 100 KT WIND SPEEDS ARE PRECISELY
IN THE AREA FROM 18N TO 21N BETWEEN 60W AND 65W. MIDDLE TO UPPER 
LEVEL DRY AIR ABOUNDS EVERYWHERE NORTHWEST OF THE JET STREAM
AND CLOUD BAND.

THE ATLANTIC OCEAN...
A SURFACE RIDGE EXTENDS FROM A BERMUDA 1021 MB HIGH PRESSURE 
CENTER TO SOUTH FLORIDA AND THE SOUTH CENTRAL GULF WATERS. UPPER
LEVEL NORTHWESTERLY FLOW ON THE EASTERN SIDE OF THE SOUTHEASTERN 
U.S.A. RIDGE EVENTUALLY FEEDS INTO THE WESTERN ATLANTIC DEEP 
LAYER TROUGH. THIS DEEP LAYER TROUGH SUPPORTS THE WESTERN 
ATLANTIC SURFACE COLD FRONT WHICH PASSES THROUGH 32N56W TO 
30N59W. THE FRONT STARTS TO DISSIPATE NEAR 30N59W AND IT 
CONTINUES TO 29N60W AND 25N66W. SCATTERED MODERATE TO ISOLATED
STRONG SHOWERS AND THUNDERSTORMS ARE WITHIN 60 NM ON EITHER SIDE 
OF THE LINE 27N60W 30N56W BEYOND 32N55W. AN UPPER LEVEL RIDGE IS 
IMMEDIATELY TO THE EAST OF THIS FRONT/DEEP LAYER TROUGH. MIDDLE 
TO UPPER LEVEL DRY AIR SURROUNDS THE TROUGH FROM 20N TO 30N 
BETWEEN 60W AND 80W...EXCEPT FOR SOME HIGH CLOUDS NORTH OF 
27N79W 28N74W 31N71W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND 
POSSIBLE PRECIPITATION ARE UNDER THIS RIDGE FROM 20N NORTHWARD 
BEYOND 32N BETWEEN 45W AND 57W. A DEEP LAYER CYCLONE AND TROUGH
SUPPORT A SURFACE FRONTAL BOUNDARY...WHOSE SOUTHERN END JUST
HAS REACHED 30N36W...AND WHICH EXTENDS NORTHEASTWARD THROUGH
31N27W BEYOND 32N25W. MIDDLE TO UPPER LEVEL DRY AIR IS NORTH
OF 20N BETWEEN AFRICA AND 30W. DEEP PRECIPITATION IS LIMITED
WITH THIS FRONT. THE FRONT IS DEFINED BY THE LINE OF CLOUDS
THAT ACCOMPANIES IT.

$$
MT