000
AXNT20 KNHC 210520
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST WED FEB 21 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 6N8W 3N15W 2N28W ACROSS THE EQUATOR 
NEAR 34W TO SOUTH AMERICA NEAR 4S43W. SCATTERED MODERATE/STRONG 
CONVECTION IS WITHIN 60/75 NM OF 3.5N FROM 9W-14W AND WITHIN 
75/90 NM OF 3.5N FROM 16W-23W. CLUSTERS OF SCATTERED MODERATE 
CONVECTION ARE FROM 5N TO S OF THE EQUATOR FROM 23W-35W. 
 
...DISCUSSION...
GULF OF MEXICO...
BROAD UPPER RIDGE AXIS EXTENDS FROM THE YUCATAN PENINSULA OVER 
THE E US TO BEYOND 32N84W. A SURFACE RIDGE OVER THE W ATLC 
EXTENDS W OVER THE GULF ALONG 27N TO 90W WITH LIGHT/MODERATE 
SOUTHERLY WINDS ACROSS THE GULF. DRY AIR REMAINS IN CONTROL OF 
THE GULF S OF 27N WITH UPPER LEVEL MOISTURE OVER THE N GULF 
COAST STATES AND ISOLATED/SCATTERED SHOWERS N OF 27N. HIGH IS 
EXPECTED TO REMAIN IN CONTROL OF THE GULF THROUGH THE END OF THE 
WEEK. 
   
CARIBBEAN SEA...
THE UPPER LEVEL TROUGH OVER THE W ATLC CLIPS THE N CARIBBEAN N 
OF 17N FROM THE VIRGIN ISLANDS TO E CUBA WITH THE ASSOCIATED 
STATIONARY FRONT DISSIPATING ACROSS THE VIRGIN/LEEWARD ISLANDS 
NEAR 18N64W SW TO 14N79W. LARGE PATCHES OF BROKEN/OVERCAST 
LOW/MID LEVEL CLOUDS WITH ISOLATED/SCATTERED SHOWERS COVERS THE 
CENTRAL CARIBBEAN FROM 13N-18N E OF 83W TO OVER THE LESSER 
ANTILLES. STRONG EASTERLY TRADE WINDS CONTINUE TO DOMINATE THE 
CARIBBEAN WITH A WEAK EASTERLY UPPER LEVEL FLOW. STRONG 
SUBSIDENCE AND DRY UPPER AIR CONTINUE TO DOMINATE THE ENTIRE 
CARIBBEAN. 

ATLANTIC OCEAN...
UPPER LEVEL TROUGH COVERS THE W ATLC W OF 50W WITH ASSOCIATED 
COLD FRONT EXTENDING INTO THE REGION NEAR 32N36W EXTENDING SW TO 
23N55W CONTINUING INTO THE CARIBBEAN AS A DISSIPATING STATIONARY 
FRONT OVER THE VIRGIN/LEEWARD ISLANDS NEAR 18N64W. BROKEN/ 
OVERCAST LOW/MID CLOUDS WITH POSSIBLE ISOLATED SHOWERS ARE 
WITHIN 120 NM E OF OF THE COLD FRONT N OF 27N WITH BROKEN/ 
OVERCAST STRATOCUMULUS CLOUDS W OF THE FRONT TO NEAR 70W. THE 
SUBTROPICAL JET IS CENTERED MOSTLY N OF THE REGION WITH WINDS OF 
90 TO 130 KT EXTENDING FROM OVER THE SE US INTO THE W ATLC N OF 
A LINE FROM 26N80W 26N60W TO BEYOND 32N40W. AN UPPER RIDGE IS 
ANCHORED IN THE E/CENTRAL ATLC NEAR 24N35W WITH THE RIDGE AXIS 
EXTENDING NE TO BEYOND 32N25W. A SHEAR AXIS EXTENDS FROM OVER 
AFRICA W INTO THE TROPICS NEAR 16N16W ACROSS S OF THE CAPE VERDE 
ISLANDS ALONG 15N43W TO NEAR 10N57W UNDERCUTTING THE UPPER RIDGE 
IN THE E/CENTRAL ATLC. SURFACE RIDGE DOMINATES THE ATLC WITH THE 
COLD FRONT FORMING A WEAKNESS AND A 1025 MB HIGH CENTERED SE OF 
BERMUDA NEAR 31N63W WITH THE RIDGE EXTENDING W INTO THE GULF OF 
MEXICO AND A 1024 MB HIGH JUST W OF THE MADEIRA ISLANDS NEAR 
32N19W. THIS SURFACE RIDGING AND DRY UPPER AIR WITH MODERATE/ 
STRONG SUBSIDENCE ARE KEEPING MOST OF THE ATLC UNDER SHOWER FREE 
CONDITIONS. 

$$
WALLACE