000
AXNT20 KNHC 200510
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST TUE FEB 20 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0445 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 6N10W 4N23W 2N30W CROSSING THE 
EQUATOR NEAR 34W TO SOUTH AMERICA NEAR 4S44W. SCATTERED 
MODERATE/STRONG CONVECTION IS FROM 1N-3N BETWEEN 3W-8W. CLUSTERS 
OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE S OF 3N 
ACROSS THE EQUATOR BETWEEN 38W-50W. 
 
...DISCUSSION...
GULF OF MEXICO...
BROAD UPPER RIDGE EXTENDS FROM THE BAY OF CAMPECHE OVER THE SE 
US WITH THE AXIS ALONG 96W. UPPER LEVEL TROUGH IS OVER THE FAR E 
GULF E OF 83W INTO THE W ATLC LEAVING THE GULF WITH ONLY 
SCATTERED/BROKEN COLD AIR STRATOCUMULUS CLOUDS. A SURFACE RIDGE 
IS OVER THE W ATLC AND THE GULF WITH A 1028 MB HIGH OFF THE SE 
US COAST WITH RETURN SURFACE FLOW DOMINATING MOST OF THE OVER 
THE GULF. DRY AIR REMAINS IN CONTROL OF THE GULF WITH SOME UPPER 
LEVEL MOISTURE OVER THE N GULF N OF 27N. THE SUBTROPICAL JET HAS 
SHIFTED N OVER THE S US COVERING THE GULF N OF 26N WITH WINDS OF 
80 TO 100 KT. 
   
CARIBBEAN SEA...
THE UPPER LEVEL TROUGH OVER THE W ATLC BARELY CLIPS THE N 
CARIBBEAN WITH THE ASSOCIATED COLD FRONT EXTENDING THROUGH THE 
VIRGIN/LEEWARD ISLANDS NEAR 18N64W SW TO 15N70W. LARGE PATCHES 
OF BROKEN/OVERCAST LOW/MID LEVEL CLOUDS WITH SCATTERED SHOWERS 
COVER THE CARIBBEAN W OF FRONT CONTINUING SW ALONG 12N77W TO 
PANAMA NEAR 9N79W. MODERATE/STRONG EASTERLY TRADE WINDS CONTINUE 
TO DOMINATE THE CARIBBEAN WITH A WEAK UPPER LEVEL RIDGE 
EXTENDING FROM CENTRAL AMERICA TO HAITI. STRONG SUBSIDENCE AND 
DRY UPPER AIR COVER THE ENTIRE CARIBBEAN WITH SOME LOW LEVEL 
MOISTURE WITH SOME WIDELY ISOLATED SHOWERS MOVING OVER THE 
WINDWARD AND ABC ISLANDS.  

ATLANTIC OCEAN...
UPPER LEVEL TROUGH OVER THE FAR E GULF OF MEXICO EXTENDS INTO 
THE W ATLC W OF 48W WITH ASSOCIATED COLD FRONT EXTENDING INTO 
THE REGION JUST NEAR 32N49W ACROSS THE VIRGIN/LEEWARD ISLANDS 
INTO THE CARIBBEAN NEAR 18N64W. A RE-ENFORCING SURGE IS 
BEGINNING TO DISSIPATE EXTENDING THROUGH 32N57W SW ALONG 27N66W 
THEN W TO THE N BAHAMA ISLANDS. BROKEN/OVERCAST LOW/MID CLOUDS 
WITH POSSIBLE ISOLATED SHOWERS ARE WITHIN 120 NM OF THE LEADING 
COLD FRONT N OF 23N. THE SUBTROPICAL JET IS CENTERED N OF THE 
REGION WITH WINDS OF 90 TO 110 KT EXTENDING FROM OVER THE N GULF 
OF MEXICO AND SE US INTO THE W ATLC N OF A LINE FROM 27N80W 
25N70W TO BEYOND 32N40W. AN UPPER RIDGE IS ANCHORED IN THE 
CENTRAL ATLC NEAR 24N44W WITH THE RIDGE AXIS EXTENDING NE TO 
BEYOND 32N34W. NARROW UPPER TROUGH IS OVER THE E ATLC EXTENDING 
THROUGH 32N12W S OVER W AFRICA NEAR 23N14W THEN AS A SHEAR AXIS 
SW INTO THE TROPICS ACROSS THE CAPE VERDE ISLANDS TO NEAR 10N49W 
UNDERCUTTING THE UPPER RIDGE IN THE CENTRAL ATLC. THE E ATLC IS 
ALSO DOMINATED BY A SURFACE RIDGE THAT EXTENDS FROM A 1027 MB 
HIGH S OF THE AZORES NEAR 33N27W SW TO 21N52W. THIS IS KEEPING 
THE AREA E OF 60W MOSTLY FAIR WITH SOME ISOLATED LOW LEVEL 
SHOWERS OVER THE CANARY ISLANDS. 

$$
WALLACE