[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 242359
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST THU FEB 24 2011

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...ITCZ...
THE ITCZ AXIS IS ANALYZED ALONG 05N09W TO 02N30W TO 00N35W TO
INLAND OVER SOUTH AMERICA AT 03S42W.  SCATTERED  MODERATE AND
ISOLATED STRONG CONVECTION WITHIN 60 NM OF AXIS E OF 13W...
WITHIN 45 NM OF AXIS 18W TO 25W AND FROM 36W TO INLAND OVER
SOUTH AMERICA.

...DISCUSSION...

GULF OF MEXICO...
ENTIRE GULF UNDER UPPER LEVEL RIDGE PRODUCING VERY DRY AIR UNDER
MODERATE TO STRONG SUBSIDENCE.  SOUTHWEST NORTH ATLANTIC SURFACE
RIDGE DRIFT FURTHER EAST ENHANCING SOUTHERLY RETURN FLOW ALONG
COAST OF TEXAS.  EARLIER EXTENSIVE AREAS OF SEA FOG WITH
VISIBILITIES BELOW 3 NM HAVE DIMINISHED IN AREA COVERAGE BUT
STILL CAN BE NOTED NORTH OF 29N FROM 83W TO 86WOW WHILE MOSTLY
LIFTED WEST OF 94W.  SCATTERED PATCHES OF RAIN STILL LINGER
ALONG TEXAS NORTHEAST COAST.  SURFACE RIDGE WILL MOVE FURTHER
EAST FORCED BY COLD FRONT APPROACHING TEXAS COAST WITH SCATTERED
SHOWERS STARTING TONIGHT THROUGH FRI.

CARIBBEAN SEA...
WEAK UPPER LEVEL TROUGH OVER WESTERN HALF OF BASIN BEING PUSHED
BY BROAD RIDGE MOVING EAST FROM GULF OF MEXICO.  VERY DRY AIR
MASS ACROSS BASIN W OF 65W WHILE MINOR AMOUNTS OF MOISTURE EAST
OF 65W IS ABSORBED IN SUCH DRY ENVIRONMENT.  UPPER LEVEL
DIFFLUENT FLOW OVER COLOMBIA MAINTAINS ASCENDING MOISTURE AND
SUPPORTS SURFACE LOW PRESSURE JUST OFF PACIFIC COAST OF
COLOMBIA.  SURFACE RIDGE OVER SW N ATLANTIC MAINTAINS CONSTANT
EAST TO NORTHEAST BREEZE ACROSS ENTIRE BASIN.  ISOLATED TO
SCATTERED QUICK MOVING LIGHT SHOWERS DOT THE LESSER ANTILLES.

ATLANTIC OCEAN...
BROAD MID TO UPPER LEVEL RIDGE MOVES EAST FORCING LONGWAVE
TROUGH INTO CENTRAL NORTH ATLANTIC.  LARGE SURFACE RIDGE 1025 MB
JUST NORTH OF REGION MAINTAINS STEADY FLOW OF EAST TO NORTHEAST
MODERATE TO FRESH BREEZE ACROSS LOWER LATITUDES EAST OF 75W
WHILE MODERATE SOUTHEAST FLOW PREVAILS WEST OF 75W.  WEAKENING
COLD FRONT FROM 31N40W TO 22N63W TO 23N66W SUPPORTED BY UPPER
LEVEL LONGWAVE TROUGH PRODUCING BROAD AREAS OF SCATTERED
CONVECTION E OF 55W BUT THINNER LINES ALONG ITS BOUNDARY FROM
55W TO 64W.

DOWNSTREAM RIDGE COMPLETES UPPER LEVEL PICTURE OVER EASTERN
ATLANTIC TO AFRICAN COAST.  SURFACE HIGH PRESSURE 1029 MB OFF
PORTUGAL COAST EXTEND TO JUST EAST OF COLD FRONT WITH WARM FRESH
BREEZE OVER AZORES ISLANDS.  FRONT EXPECTED TO MOVE SOUTHEAST
AND STALL AS UPPER LEVEL SUPPORT SHIFT NE.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
WALLY BARNES



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