000
AXNT20 KNHC 181756
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST FRI FEB 18 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...ITCZ...

THE ITCZ IS ANALYZED FROM W AFRICA NEAR 05N8W TO 06N16W TO 
02N30W THEN S OF THE EQUATOR NEAR 40W INTO SOUTH AMERICA NEAR 
01S48W. CLUSTERS OF SCATTERED MODERATE ISOLATED STRONG 
CONVECTION ARE LOCATED FROM THE EQUATOR TO 07N BETWEEN 06W AND 
16W. SCATTERED STRONG CONVECTION IS LOCATED ALONG THE SOUTH 
AMERICA COAST FROM THE EQUATOR TO 05N CONTINUING OFFSHORE UP TO 
150 NM.

...DISCUSSION...

GULF OF MEXICO...
BROAD RIDGING ALOFT COVERS MOST OF THE GULF WITH WATER VAPOR 
IMAGERY INDICATING STRONG SUBSIDENCE ACROSS THE ENTIRE AREA. 
WINDS ALOFT ARE STRONGEST OVER THE NW GULF AND MEASURE IN THE 40 
TO 50 KNOT RANGE. THIS PATTERN WILL CHANGE LITTLE OVER THE NEXT 
48 HOURS. AT THE SURFACE A 1025 MB HIGH IS ANCHORED OVER THE 
EASTERN FLORIDA PANHANDLE. SOUTHEAST WINDS IN THE 10 TO 15 KNOT 
RANGE ARE OVER MOST OF THE AREA. A COLD FRONT WILL MOVE INTO 
THE NW GULF TUESDAY MORNING.

CARIBBEAN SEA...
WESTERLIES ALOFT COVER THE ENTIRE CARIBBEAN BASIN WITH THE 
STRONGEST WINDS N OF ABOUT 16N AND MEASURE UP TO 60 KNOTS. THE 
SOUTHERN PART OF A MIDDLE/UPPER LEVEL TROUGH OVER THE W CENTRAL 
ATLANTIC IS PUSHING SE ACROSS HISPANIOLA AND INTO THE NE 
CARIBBEAN. LIKE THE GULF OF MEXICO STRONG SUBSIDENCE ALOFT 
COVERS THE CARIBBEAN. TRADE WINDS ARE LOCATED ACROSS THE AREA 
AND ARE FORECAST TO INCREASE SATURDAY NIGHT THROUGH MONDAY. 

ATLANTIC OCEAN...
A MIDDLE/UPPER LEVEL TROUGH DOMINATES THE FLOW W OF ABOUT 55W 
WITH THE AXIS LOCATED THROUGH 32N58W ACROSS HISPANIOLA. STRONG 
SUBSIDENCE ALOFT IS LOCATED S OF 25N W OF 62W. A JET ORIGINATES 
NEAR THE BASE OF THE TROUGH AT 18N67W AND CONTINUES NE THROUGH 
24N60W TO 30N53W AND THEN TURNS MORE ENE BEYOND 32N45W. 
SATELLITE DERIVED WINDS INDICATE WINDS AS HIGH AS 110 KNOTS 
BETWEEN 45W AND 58W. A BROAD RIDGE ALOFT IS LOCATED OVER THE 
TROPICS S OF ABOUT 18N BETWEEN 35W AND 58W. WESTERLIES ALOFT 
COVER MOST OF THE EASTERN HALF OF THE ATLANTIC N OF ABOUT 10N. A 
MIDDLE/UPPER LEVEL SHORTWAVE TROUGH HAS ITS AXIS LOCATED ALONG 
26W/27W FROM 10N TO 15N. AT THE SURFACE A 1028 MB HIGH IS 
LOCATED NEAR 31N64W. A COLD FRONT EXTENDS THROUGH 32N25W TO 
25N39W AND THEN CONTINUES AS A FRONTAL TROUGH TO 24.5N44W AND 
THEN CONTINUES AS A SHEAR LINE TO 19N69W. THE ABOVE FEATURE IS 
MARKED BY A 2 TO 3 DEGREE WIDE BAND OF BROKEN/OVERCAST LOW/ 
MIDDLE LEVEL CLOUDS.

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

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CAB