[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 010551
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST THU JAN 01 2009

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...THE ITCZ...

ITCZ IS CENTERED ALONG A LINE FROM 08N13W TO 04N29W TO 02N51W.
SCATTERED MODERATE CONVECTION NOTED WITHIN 60 NM S OF AXIS
BETWEEN 40W AND 44W.

...DISCUSSION...

GULF OF MEXICO...
STATIONARY COLD FRONT EXTENDS FROM 28N83W NEAR TAMPA FLORIDA TO
26N97W NEAR BROWNSVILLE TEXAS. SW FLOW ALOFT AHEAD OF A WEAK
SHORT WAVE TROUGH MOVING OVER THE NW GULF IS INITIATING POCKETS
OF MODEST CONVECTION ALONG THE BOUNDARY W OF 93W...THAT WILL
SHIFT EASTWARD ALONG THE BOUNDARY THROUGH THIS MORNING. LITTLE
LIGHTNING IS NOTED WITH THIS ACTIVITY. SHIP AND BUOY
OBSERVATIONS SHOW 15 TO 20 KT NE WINDS TO THE N OF THE
BOUNDARY...ON THE SOUTHERN EDGE OF HIGH PRES BUILDING OVER THE
TENNESSEE VALLEY BEHIND THE FRONT. THE SUPPORTING TROUGH FOR THE
FRONT IS LIFTING OUT THROUGH NEW ENGLAND. THE FRONT SUBSEQUENTLY
DISSIPATES AND WINDS SUBSIDE THROUGH FRI WITH LIGHT TO MODERATE
RETURN FLOW AS THE HIGH PRES SHIFTS EAST.

CARIBBEAN SEA...
SHIP AND BUOY OBSERVATIONS INDICATED 15 TO 20 KT TRADES PERSIST
OVER THE CENTRAL CARIBBEAN...WITH SOME HINTS OF UP TO 25 KT OFF
THE COLOMBIAN COAST. ELSEWHERE...ONLY LIGHT TO MODERATE TRADES
ARE NOTED. AREA SOUNDINGS AND WATER VAPOR IMAGERY SHOW THAT MID
AND UPPER LEVELS REMAIN VERY DRY IN SW FLOW. NO SIGNIFICANT
WEATHER IS NOTED. SURFACE WINDS WILL START TO INCREASE ACROSS
THE BASIN ON FRI AS HIGH PRES BUILDS NORTH OF THE AREA.

ATLANTIC...
AN AMPLIFIED UPPER PATTERN CONTINUES OVER THE ATLANTIC WITH A
RIDGE BUILDING ALONG 20W AHEAD OF AN UPPER TROUGH FROM ROUGHLY
THE AZORES TO 30N45W. THE TROUGH IS LIFTING NE...PULLING SUPPORT
FROM AN ASSOCIATED FRONTAL BOUNDARY THAT IS DISSIPATING FROM
32N41W TO 28N53W. A SURFACE RIDGE EXTENDS NEAR THE CANARY
ISLANDS WESTWARD ALONG 23N TO THE BAHAMAS. NE OF THE BAHAMAS...A
COLD FRONT EXTENDS FROM NEAR 32N71W TO CENTRAL FLORIDA. BUOY
OBSERVATIONS SHOW 20 TO 25 KT FROM THE NW BEHIND THE FRONT...AND
THE SW JUST AHEAD OF THE FRONT. BUOY AND ASCAT DATA SHOW A BROAD
AREA OF GENERALLY 15 TO 20 KT TRADES SOUTH OF THE RIDGE AXIS AND
N OF 10N. SCATTERED CONVECTION IS NOTED ALONG THE ITCZ NEAR THE
MOUTH OF THE AMAZON RIVER WHERE ENHANCED SOUTHERLY FLOW IS
AIDING LOW LEVEL CONVERGENCE.

$$
CHRISTENSEN



This weather bulletin was brought to you by:
www.nashvilleweather.net