000
AXNT20 KNHC 211202
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST SUN JAN 21 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 1115 UTC.

...THE ITCZ...
4N4W 4N20W 4N30W 3N40W 2N46W...CURVING TO THE EQUATOR AT 50W
AND TO NORTHEASTERN BRAZIL NEAR 1S52W. ISOLATED MODERATE SHOWERS
TO LOCALLY STRONG THUNDERSTORMS FROM 1N TO 4N BETWEEN 20W AND 
35W.

...DISCUSSION...
THE GULF OF MEXICO...THE WESTERN CARIBBEAN SEA...AND THE
ATLANTIC OCEAN WEST OF 50W...
MIDDLE TO UPPER LEVEL SOUTHWESTERLY WIND FLOW MOVES FROM
MEXICO NORTH OF 20N...ACROSS ALL OF TEXAS AND NORTHWARD BEYOND 
TEXAS...IN RESPONSE TO A CENTRAL U.S.A. MIDDLE TO UPPER LEVEL 
TROUGH. THE MIDDLE TO UPPER LEVEL RIDGE RUNS FROM THE 
SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO CUBA BEYOND 32N79W
IN THE ATLANTIC OCEAN. MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE 
STILL KEEPING THE AREA FREE OF DEEP CONVECTIVE PRECIPITATION. 
UPPER LEVEL MOISTURE IS PRESENT NORTH OF 22N AT THE MEXICO COAST 
TO 26N90W BEYOND 30N82W. A WARM FRONT EXTENDS FROM THE 
NORTHEASTERN GULF WATERS TO A 1013 MB LOW PRESSURE CENTER ALONG 
THE WEST CENTRAL LOUISIANA BORDER WITH EAST TEXAS. A COLD FRONT 
EXTENDS FROM THIS LOW CENTER INTO THE WESTERN GULF WATERS TO 
25N97W ALONG THE MEXICO COAST TO 25N100W INLAND. 
THE ANTICYCLONIC FLOW AROUND THE RIDGE MOVES FROM GEORGIA/
SOUTH CAROLINA INTO THE ATLANTIC OCEAN...TO THE BASE OF A MIDDLE 
TO UPPER LEVEL TROUGH NEAR 30N60W. THE FLOW BECOMES SPLIT JUST 
NORTH AND EAST OF 30N60W...WITH SOME OF IT GOING NORTHWARD IN 
RESPONSE TO THE TROUGH...AND THE SOME OF IT GOING SOUTHEASTWARD 
IN THE DIRECTION OF ANOTHER ATLANTIC OCEAN TROUGH NEAR 14N33W.

THE REST OF THE CARIBBEAN SEA...
MIDDLE TO UPPER LEVEL ANTICYCLONIC FLOW AND DRY AIR/SUBSIDENCE
COVER THE AREA. POSSIBLE SHOWERS IN SCATTERED TO BROKEN LOW TO 
MIDDLE LEVEL CLOUDS...FROM 12N TO THE GREATER ANTILLES BETWEEN 
60W AND JAMAICA...NORTH OF 12N BETWEEN JAMAICA AND 80W...AND
MOSTLY SOUTH OF 16N WEST OF 80W. SIMILAR CLOUDS AND POSSIBLE
PRECIPITATION HAVE MOVED INTO AND/OR ARE MOVING INTO NICARAGUA 
AND THE EASTERN HALF OF HONDURAS.

THE REST OF THE ATLANTIC OCEAN EAST OF 50W...
A COLD FRONT PASSES THROUGH 31N53W 28N60W 26N70W 28N80W.
THE COMPARATIVELY THICKEST LOW CLOUDS ARE NORTH OF 31N52W 28N60W
26N70W 28N80W. A 1018 MB HIGH PRESSURE CENTER IS NEAR 23N55W.
A MIDDLE TO UPPER LEVEL TROUGH IS ALONG 31N32W 23N32W 14N33W. 
SHOWERS ARE WITHIN 15 NM ON EITHER SIDE OF 35W FROM 25N TO 26N. 
A SURFACE TROUGH RUNS FROM A 1008 MB LOW PRESSURE CENTER NEAR 
31N41W TO 24N42W. AN UPPER LEVEL RIDGE IS ALONG 10N23W TO 
23N23W. SHOWERS AND POSSIBLE THUNDERSTORMS ARE NORTH OF 31N 
BETWEEN 29W AND 36W.

$$
MT