000
AXNT20 KNHC 060550
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST SAT JAN 06 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 
0545 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 2N AT THE PRIME MERIDIAN TO 14W THEN 
ALONG 5N25W 3N40W TO NE BRAZIL NEAR 1N50W. ISOLATED CLUSTERS OF 
MODERATE CONVECTION NOTED WITHIN 150 NM OF THE AXIS BETWEEN 
18W-42W. 

...DISCUSSION...
GULF OF MEXICO...
SW PORTION OF ATLC RIDGE IS NOW TAKING OVER THE GULF SFC 
PATTERN. THE COLD FRONT THAT HAS BEEN MOVING E THROUGH THE NRN 
GULF OVER THE LAST COUPLE OF DAYS IS NOW DISSIPATING AS OF 0300 
UTC...WITH LIGHT SLY FLOW ALONG WITH A WEAK WARM ADVECTION 
PATTERN OVER MUCH OF THE GULF INCLUDING THE AREA BEHIND THE OLD 
COLD FRONT. THERE IS STILL AN AREA OF MODERATE SHOWERS JUST WEST 
OF THE TAMPA AREA...THOUGH THESE ARE ALSO DIMINISHING WITH THE 
SUPPORTING DYNAMICS NOW MOSTLY NE OF THE AREA OVER THE CAROLINAS 
AND ADJACENT ATLC WATERS. MUCH DRIER MID TO UPPER AIR IS SEEN IN 
THIS EVENINGS WV IMAGERY OVER THE GULF IN COMPARISON TO 24 HOURS 
AGO...ROTATING AROUND THE UPPER RIDGING NOW DOMINATING BEHIND 
THE DEEP LAYERED TROUGH LIFTING NE OF THE AREA. NEXT FRONTAL 
SYSTEM WILL PUSH THROUGH THE GULF LATE SAT THROUGH EARLY NEXT 
WEEK...SEE MIAOFFNT4 FOR DETAILS. 

CARIBBEAN SEA...
UPPER RIDGE EXTENDING N FROM PANAMA CONTINUES TO COVER THE W 
CARIBBEAN W OF 70W. MID TO UPPER TROUGH IN THE W/CENTRAL ATLC 
EXTENDS S OVER THE REMAINDER OF THE CARIBBEAN ACROSS THE LESSER 
ANTILLES INTO THE W TROPICAL ATLC. DRY AIR AND STRONG SUBSIDENCE 
DOMINATES THE ENTIRE CARIBBEAN LEAVING ONLY WIDELY ISOLATED LOW 
LEVEL SHOWERS DOTTING THE REGION. EASTERLY TRADE WINDS 15-25 KT 
CONTINUE TO DOMINATE THE CARIBBEAN. THIS CONTINUES THROUGH THE 
WEEKEND BEING STRONGEST NEAR THE COLOMBIAN COAST.  

ATLANTIC OCEAN...
LINE OF HEAVY SHOWERS WITH EMBEDDED TSTMS SEEN ON RADAR IMAGERY 
JUST OFF THE GEORGIA/SOUTH CAROLINA COAST. THIS IS ASSOCIATED 
WITH THE UNSTABLE ENVIRONMENT AHEAD OF THE FRONT NOW DISSIPATING 
OVER THE SE U.S....ALONG WITH THE DYNAMICS ASSOCIATED WITH THE 
SHORTWAVE UPPER TROUGH PUSHING OFF THE EAST COAST. ASSOCIATED 
ABUNDANT MOISTURE NE OF THE BAHAMAS IS SEEN MOVING AROUND 
AN UPPER RIDGE JUST E OF THE TROUGH. A PRONOUNCED UPPER TROUGH 
IS OVER THE W-CENTRAL ATLC WATERS BETWEEN 40W-65W. ASSOCIATED 
SFC TROUGH IS ALONG 31N46W 20N55W WHICH HAS SCATTERED MODERATE 
CONVECTION FROM 19N-30N BETWEEN 48W-56W. REMAINDER OF THE W AND 
CENTRAL ATLC SFC PATTERN DOMINATED BY ANTICYCLONIC FLOW AROUND 
THE 1032 MB HIGH N OF THE AREA NEAR 34N55W. SMALL 
NEGATIVELY TILTED UPPER TROUGH IS ALONG 32N32W 24N23W. 
DIFFLUENCE BETWEEN THIS FEATURE AND THE UPPER RIDGE JUST TO ITS 
E HAS AN AREA OF SIGNIFICANT MOISTURE WITH EMBEDDED SHOWERS N OF 
21N E OF 32W. UPPER RIDGING OVER MUCH OF THE TROPICAL ATLC IS 
ADVECTING MOISTURE/HIGH CLOUDS EWD FROM 55W THROUGH AFRICA S OF 
23N. SFC RIDGING ALSO OVER THE ERN ATLC WATERS FROM A 1034 MB 
CENTER JUST N OF THE MADEIRA ISLANDS. 

$$
WILLIS