000
AXNT20 KNHC 010011
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST WED FEB 28 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2345 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 7N11W 3N20W 2N30W CROSSING 
THE EQUATOR AT 42W...INTO NORTHEASTERN BRAZIL NEAR 2S48W. 
ISOLATED MODERATE CONVECTION IS WITHIN 90 NM OF THE AXIS BETWEEN 
THE COAST OF AFRICA AND 17W....AND WITHIN 150 NM OF AXIS BETWEEN 
37W AND COASTAL BRAZIL. 

...DISCUSSION...

THE GULF OF MEXICO...
COMPLEX FRONTAL PATTERN CONTINUES TO DOMINATE THE ERN 
GULF...THOUGH THINGS SEEM A LITTLE MORE SORTED OUT THAN 
YESTERDAY. THE LAST FEW VISIBLE PICTURES THIS EVENING SHOW A 
REGION OF LOW LEVEL CONFLUENCE WITH A CLUSTER OF MODERATE 
CONVECTION FROM 24N-28N BETWEEN 83W-91W...WHERE ESE FLOW IN THE 
NE GULF IS COLLIDING WITH MORE SLY FLOW SPREADING N THROUGH THE 
YUCATAN CHANNEL. AS OF 2100 UTC...HAVE PLACED A FORMING WARM 
FRONT THROUGH THIS ZONE FROM SW FLORIDA TO SRN LOUISIANA ALONG 
26N82W 26N87W 29N91W. THIS IS A BIT OF A CHANGE FROM EARLIER 
MAPS BUT THINK THE SATELLITE SIGNATURE AND SFC OBS...ESPECIALLY 
THE DEWPOINTS...JUSTIFY SUCH A CHANGE. MUCH OF THE REMAINDER OF 
THE GULF IS SEEING JUST PATCHES OF BENIGN LOW CLOUDS...IN 
ADDITION TO HIGH CIRRUS SPREADING SE THROUGH THE AREA N OF 22N 
WITH DOMINATING UPPER NW FLOW AROUND RIDGING. SLY SFC WINDS WILL 
INCREASE TONIGHT INTO THU AHEAD OF THE NEXT FRONT TO PUSH OFF 
THE TEXAS COAST INTO THU AFTERNOON. 

THE CARIBBEAN SEA...
THE MAIN STORY IN THE CARIBBEAN CONTINUES TO BE THE BRISK ELY 
TRADES OVER MUCH OF THE AREA E OF 82W. THE TRADE FLOW CONTINUES 
TO BE STRONGEST NEAR THE COLOMBIAN COAST WHERE GALE CONDITIONS 
ARE EXPECTED THROUGH EARLY SAT. THIS WILL ALSO CONTINUE TO 
SEND MODERATE TO STRONG SURF TO THE CARIB COAST OF 
NICARAGUA...COSTA RICA...AND PANAMA OVER THE NEXT FEW DAYS. A 
BIT LIGHTER SE FLOW IS SEEN IN THE NW CARIBBEAN...AROUND THE SW 
PORTION OF ATLC HI PRES AND IN ADVANCE OF THE SYSTEM DEVELOPING 
OVER THE CENTRAL USA. THE TRADES ARE ADVECTING TYPICAL PATCHES 
OF LOW LEVEL MOISTURE WWD. HOWEVER...VERY LITTLE CLOUD COVER IS 
SEEN OVER THE CENTRAL CARIB WATERS WHERE THE TRADES ARE 
STRONGEST WHICH HAS LED TO A WELL MIXED LOWER ATMOSPHERE. ON THE 
CONTRARY...SPEED CONFLUENCE HAS LED TO A REGION OF BROKEN LOW 
CLOUDS FROM THE COAST OF PANAMA TO 14N BETWEEN 78W-82W. 
ALOFT...VERY DRY AND STABLE AIR DOMINATES YET AGAIN WHICH HAS 
BEEN THE STORY FOR MUCH OF THE WINTER. THIS DRY AIR IS ROTATING 
AROUND A MID TO UPPER TROUGH EXTENDING SW BETWEEN CUBA AND 
CENTRAL AMERICA...AND RIDGING OVER THE ERN CARIB. 

THE ATLANTIC OCEAN...
AS OF 28/2100 UTC A COLD FRONT ENTERS THE AREA NEAR 30N64W AND 
CONTINUES WSW TO NEAR 27N76W WHERE IT BECOMES A DISSIPATING COLD 
FRONT NEAR PALM BEACH. THE ERN PORTION OF THIS FRONT HAS BEEN 
FAIRLY STRAIGHTFORWARD WITH A RESEMBLANCE OF A ROPE CLOUD SEEN E 
OF ABOUT 70W. THINGS HAVE BEEN MORE CHALLENGING TO THE W THOUGH. 
A SHARP UPPER SHORTWAVE TROUGH IS EXTENDING S THROUGH THE WRN 
ATLC AND CENTRAL BAHAMAS. SCATTERED MODERATE CONVECTION IS IN 
THE DIFFLUENT ZONE AHEAD OF THIS TROUGH FROM 23N-28N BETWEEN 
69W-74W. THERE ALSO APPEARS TO BE SOME SFC TROUGHING AHEAD OF 
THE MAIN FRONT THAT IS RESPONSIBLE FOR THE SCATTERED MODERATE 
CONVECTION WITHIN 90 NM OF A LINE FROM 23N69W 32N50W. HOPING 
THAT TONIGHTS QUIKSCAT PASS WILL SHED SOME LIGHT ON ANY LOWS 
THAT MAY HAVE DEVELOPED ON THE COMPLEX FRONTAL PATTERN OVER THE 
WRN ATLC.  THE REMAINDER OF THE E AND CENTRAL ATLC SFC PATTERN 
IS DOMINATED BY THE 1030 MB HIGH NEAR 32N24W...WHICH IS 
PRODUCING ABUNDANT FAIR WEATHER AND MODERATE TRADES. BROAD UPPER 
RIDGING ALSO DOMINATES MUCH OF THE CENTRAL AND E ATLC AS 
WELL...THOUGH AN UPPER TROUGH SURROUNDED BY VERY DRY AIR IS N OF 
12N OFF THE COAST OF AFRICA. 


$$
WILLIS