000
AXNT20 KNHC 081120
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
705 AM EST TUE FEB 08 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

...ITCZ...

THE ITCZ AXIS IS ANALYZED FROM THE COAST OF LIBERIA NEAR 6N11W 
WESTWARD ALONG 1N20W EQ30W 2N40W 1S48W. WIDELY SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS FROM 1N-7N BETWEEN 
23W-46W. SIMILAR CONVECTION IS ALSO WITHIN 50 NM ON EITHER SIDE 
OF THE AXIS BETWEEN 20W-30W.

...DISCUSSION...

GULF OF MEXICO...
THE COLD FRONT THAT WAS MOVING ACROSS THE GULF IN THE PAST 24 
HOURS IS NOW OVER THE WEST ATLC. HENCE...A COLD AND DRY AIRMASS 
HAS TAKEN OVER THE BASIN IN THE WAKE OF THE FRONT. MARINE OBS 
ACROSS THE GULF INDICATE A MORE RELAX PRESSURE GRADIENT WITH 
NORTHERLY WINDS UP TO 15 KT EVERYWHERE EXCEPT W OF 92W...WHERE 
THE FLOW TURNS ANTI-CYCLONIC BANKING SOME LOW LEVEL MOISTURE 
OVER THE BAY OF CAMPECHE S OF 20N...GENERATING A FEW ISOLATED 
SHOWERS IN THIS REGION. DRY/SUBSIDENT AIR ALOFT PREDOMINATES IN 
THE UPPER LEVELS OF THE ATMOSPHERE ACROSS THE GULF...WITH NO 
SIGNIFICANT CHANGES EXPECTED OVER THE NEXT 24 HOURS. 

CARIBBEAN SEA...
THE SOUTHERN EXTENSION OF THE COLD FRONT MENTIONED IN THE ATLC 
OCEAN DISCUSSION MOVES ACROSS THE FAR NW CARIBBEAN ANALYZED FROM 
WESTERN CUBA TO THE COAST OF GUATEMALA ALONG 23N81W 20N85W 
16N88W. SATELLITE IMAGERY SHOWS SCATTERED SHOWERS AND ISOLATED 
THUNDERSTORMS WITHIN 25 NM AHEAD OF THE FRONT. COMPUTER MODELS 
SUGGEST THIS BOUNDARY WILL WEAKEN AS IT TRACKS EAST OVER THE 
NEXT 6 TO 9 HRS WITH CONVECTION AFFECTING MOSTLY NW BASIN N OF 
15N W OF 80W. OTHERWISE...A VERY DRY AND SUBSIDENT AIRMASS 
CONTINUES TO DOMINATE THE CARIBBEAN SEA THIS MORNING...PROVIDING 
MOSTLY FAIR WEATHER CONDITIONS ELSEWHERE ACROSS THE BASIN. AT 
SURFACE...TRADE WINDS ARE ACROSS MUCH THE AREA AND BEGIN TO 
TURN CYCLONICALLY AROUND THE COLOMBIAN COAST. THIS FLOW 
CONTINUES TO ADVECT SOME LOW LEVEL MOISTURE FROM THE TROPICAL 
ATLC INTO THE BASIN...PROVIDING WEAK SCATTERED SHOWERS ACROSS 
THE EASTERN BASIN E OF 70W S OF 15N. SIMILAR ACTIVITY IS 
HAPPENING OVER THE N CENTRAL BASIN N OF 15N BETWEEN 70W-77W. AS 
THE FLOW TURNS CYCLONICALLY IN THE SW BASIN...LOW LEVEL 
CONVERGENCE DEVELOPS NEAR THE COASTAL WATERS OF NICARAGUA AND 
EASTERN HONDURAS W OF 82W S OF 18N SUPPORTING SCATTERED WEAK 
SHOWERS IN THIS REGION. 

ATLANTIC OCEAN...
A BROAD UPPER LEVEL LONGWAVE/TROUGH MOVES OFF THE ERN CONUS 
SEABOARD...SUPPORTING A COLD FRONT THAT ENTERS THE DISCUSSION 
AREA NEAR 32N71W EXTENDING SW TO ACROSS WESTERN CUBA NEAR 
23N81W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE 
DEVELOPING WITHIN 40 NM AHEAD OF THE FRONT. THIS FRONT IS 
EXPECTED TO PROPAGATE EASTWARD WITH CONVECTION AFFECTING THE W 
ATLC BASIN AND THE COASTAL WATERS ACROSS THE BAHAMAS. OTHERWISE 
...A BROAD UPPER LEVEL RIDGE OF HIGH PRESSURE COVERS THE 
REMAINDER OF THE ATLC AND SUPPORTS A 1028 MB HIGH NEAR 30N50W. 
THIS FEATURE IS PROVIDING FAIR WEATHER CONDITIONS E OF 70W. 
HOWEVER...A NARROW UPPER LEVEL TROUGH EXTENDS ACROSS THE EAST 
ATLC... SUPPORTING A COLD FRONT THAT ENTERS OUR DISCUSSION AREA 
ALONG 32N21W TO 27N28W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 20 
NM ON EITHER SIDE OF THE AXIS. SURFACE RIDGING CONTINUES E OF 
THIS SYSTEM. 

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

$$

GARCIA