000 AXNT20 KNHC 212350 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 6N10W 4N20W 2N30W CROSSING THE EQUATOR AT 40W AND INTO NE BRAZIL. ISOLATED CLUSTERS OF MODERATE CONVECTION ARE ALONG THE ITCZ AXIS. CLUSTERS OF MODERATE TO ISOLATED STRONG CONVECTION AREA OVER NE BRAZIL. ...DISCUSSION... GULF OF MEXICO... WEAK PRESSURE PATTERN CHARACTERIZED BY WEAK RIDGING AND A 1010 MB SFC LOW NEAR 20N95W DOMINATES THE GULF. THIS IS PRODUCING LIGHT SLY FLOW E OF 80W. AS OF 21Z...A TROF IS ANALYZED FROM THE FLORIDA PANHANDLE SW TO 27N90W. A ROPE OR LINE CLOUD DELINEATES THIS TROUGH. ANOTHER SFC TROUGH IS OVER THE SE GULF AND THE YUCATAN PENINSULA AND RUNS FROM 24N87W TO N GUATEMALA NEAR 16N89W. LATEST VIS SAT IMAGERY INDICATES THAT THE LOW OVER THE SW GULF IS WEAKENING. BROKEN TO OVERCAST DEEP LAYER CLOUDS WITH EMBEDDED SHOWERS/ISOLATED TSTMS ARE OVER THE NE GULF WATERS COVERING ALSO THE FLORIDA PANHANDLE AND PARTS OF GEORGIA AND SOUTH CAROLINA. THIS CONVECTIVE ACTIVITY IS ASSOCIATED WITH A SHORTWAVE TROUGH MOVING EWD ACROSS THE SE US. STRONG MID/UPPER RIDGE CENTERED OVER GUATEMALA/SOUTH MEXICO COVERS THE ENTIRE GULF. SOME UPPER LEVEL MOISTURE IS BEING ADVECTED ACROSS N MEXICO INTO THE N GULF WATERS BY A SUBTROPICAL JET WITH CORE WINDS OF 90 TO 110 KT. HIGH PRES RIDGE ACROSS THE GULF WILL SHIFT E AND WEAKEN THROUGH FRI. RETURN FLOW WILL ESTABLISH AGAIN ON SAT AHEAD OF A NEW COLD FRONT APPROACHING THE TEXAS COAST. CARIBBEAN SEA... HIGH PRES LOCATED N OF THE AREA IS PRODUCING MODERATE TO STRONG TRADES ACROSS THE BASIN WITH THE STRONGEST WINDS OFF THE COAST OF COLOMBIA. EARLIER QUIKSCAT PASS SHOWED WINDS OF 20 TO 30 KT. THIS WEATHER PATTERN WILL PERSIST DURING THE NEXT FEW DAYS. TYPICAL PATCHES OF LOW LEVEL MOISTURE WITH EMBEDDED SHOWERS DRIVEN BY THE TRADES ARE AFFECTING THE AREA...PARTICULARLY THE E CARIBBEAN. SOME OF THEM ARE CURRENTLY MOVING ACROSS PUERTO RICO AND HISPANIOLA AS WELL AS OVER THE OFFSHORE VENEZUELA ISLANDS/ABC ISLANDS. EXTREMELY DRY/STABLE MID TO UPPER AIR CONTINUES TO HOVER OVER THE CARIBBEAN...AROUND RIDGING EXTENDING E THROUGH THE BASIN FROM GUATEMALA. ATLANTIC OCEAN... WEAK HIGH PRES RIDGE WITH THREE HIGH PRES CENTERS DOMINATES THE ENTIRE FORECAST AREA. THE HIGHS ARE CENTERED NEAR 25N69W... 32N44W...AND WEST OF THE CANARY ISLANDS NEAR 27N23W. THE FRONTAL SYSTEM THAT REACHED THE NE CARIBBEAN IS NOW MOVING N AS A WARM FRONT. IT LIES ALONG 34N34W...28N45W 23N60W. BROKEN LOW TO MID CLOUDS WITH EMBEDDED SHOWERS ARE WITHIN 120 NM OF THE FRONT. THE FRONT CONTINUES TO WEAKEN WITH LITTLE THERMAL CONTRAST NOTED. ALOFT...A RIDGE/TROUGH/RIDGE PATTERN DOMINATES THE FORECAST REGION N OF 15N. THE RIDGE OVER THE GULF EXTENDS ACROSS FLORIDA INTO THE W-CENTRAL ATLC WHILE A WEAK UPPER TROUGH IS ALONG 50/51W. ANOTHER RIDGE CENTERED NEAR 19N31W EXTENDS OVER THE REMAINDER OF THE OCEAN. AN UPPER TROUGH REMAINS INLAND OVER NW AFRICA. FAIRLY DRY MID TO UPPER AIR IS ALSO SEEN BETWEEN 60W-25W. AN UPPER LOW IS SPINNING OVER THE CAPE VERDE ISLANDS. THE SUBTROPICAL JET REMAINS CENTERED JUST N OF THE REGION WITH WINDS OF 90 TO 110KT . $$ GR