000 AXNT20 KNHC 101206 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU MAY 10 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1030 UTC. ...SPECIAL FEATURE... SUBTROPICAL STORM ANDREA WAS CENTERED NEAR 30.1N 79.8W AT 10/0900 UTC OR ABOUT 100 MILES E OF JACKSONVILLE FLORIDA AND 95 MILES NE OF DAYTONA BEACH FLORIDA. ANDREA IS GENERALLY DRIFTING SOUTHWARD AND THIS SLOW MOTION IS EXPECTED OVER THE NEXT 24 HOURS. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. MAXIMUM SUSTAINED WINDS ARE 35 KT WITH GUSTS TO 45 KT. SOME WEAKENING IS FORECAST DURING THE NEXT 24 HOURS. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/ WTNT21 KNHC FOR MORE DETAILS. THE COMBINATION OF SHEAR AND DRY AIR IS INHIBITING CONVECTION AND DISPLACING THE CONVECTION THAT DOES EXIST TO THE EAST OF THE CENTER. SCATTERED MODERATE CONVECTION IS CURRENTLY FROM 29N-32N BETWEEN 76W-80W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 9N13W 7N20W 4N30W EQ50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 16W-38W. SCATTERED MODERATE ALSO FROM EQ-5N BETWEEN 47W-53W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYER N TO NW FLOW ON THE W SIDE OF ANDREA IS ENHANCING SUBSIDENCE ABOVE THE ERN HALF OF THE GULF PROVIDING WIDESPREAD CLEAR SKIES AND FAIR WEATHER. MOST OF THE SMOKE PLUMES ORIGINATING FROM FIRES IN FLORIDA AND S GEORGIA HAVE CONTINUE TO SPREAD INTO THE BAY OF CAMPECHE AND INTO THE WRN ATLC...STEERED BY THE DIFFLUENT LOW-LEVEL FLOW BETWEEN ANDREA AND A WEAK 1016 MB HIGH PRES OFF THE COAST OF LOUISIANA. THE HIGH IS PRODUCING MOSTLY LIGHT 5-15 KT WINDS ACROSS THE GULF AIDING IN THE TRANQUIL CONDITIONS. SEAS HAVE ALSO CONTINUED TO COME DOWN ACROSS THE GULF OVER THE LAST 24 HOURS WITH MOST BUOYS/SHIPS NOW IN THE 1-3 FT RANGE. FAIRLY LIGHT WINDS AND MOSTLY FAIR WEATHER IS EXPECTED TO CONTINUE THROUGH FRI AS WEAK HIGH PRES REMAINS STATIONARY IN THE MID-GULF...THOUGH SCATTERED SHOWERS/TSTMS POSSIBLE IN THE NW PORTION AS THE UPPER LOW CURRENTLY OVER N TEXAS APPROACHES THE REGION. CARIBBEAN SEA... THE CONTINUED WEAK PRES PATTERN IN THE WRN CARIB IS ALLOWING WINDS TO REMAIN VERY LIGHT...GENERALLY 10 KT OR LESS. THE TRADES INCREASE TO MORE TYPICAL VALUES IN THE CENTRAL AND ERN CARIB...15-20 KT...AS SFC RIDGING FROM THE NE HAS BUILT INTO THE REGION. SIMILAR CONDITIONS EXPECTED OVER THE NEXT COUPLE OF DAYS. A SFC TROUGH EXTENDING SSW FROM THE WINDWARD PASSAGE IS ANALYZED IN THE LOW LEVEL CONFLUENT ZONE ALONG 20N74W 17N78W 12N79W. THIS...ALONG WITH UPPER LEVEL DIFFLUENCE...IS SUPPORTING THE SCATTERED SHOWERS/ISOLATED TSTMS N OF 12N BETWEEN 72W-80W. MORE IMPRESSIVE CONVECTION ASSOCIATED WITH THE ITCZ IS OVER COLOMBIA..PANAMA...AND ADJACENT WATERS S OF 12N E OF 81W. UPPER SW FLOW BETWEEN A TROUGH/RIDGE PATTERN IS TRANSPORTING UPPER MOISTURE OVER THE CONVECTION NE INTO THE ATLC. ATLANTIC... SUBTROPICAL STORM ANDREA REMAINS THE AREA OF FOCUS THIS EVENING...FOR DETAILS REFER TO THE SPECIAL FEATURE SECTION ABOVE. SWELL ASSOCIATED WITH ANDREA HAS CONTINUED TO OVERALL STEADILY SUBSIDE OVER THE LAST COUPLE OF DAYS. HOWEVER...SEAS HAVE BEEN SLOWER TO RELAX OFF GEORGIA THROUGH SOUTHERN NORTH CAROLINA COAST...DOWNSTREAM FROM A MORE FAVORABLE FETCH ASSOCIATED WITH THE INTERACTION BETWEEN ANDREA AND A 1026MB HIGH PRES OFF THE MID ATLC COAST NEAR 37N55W. AN UPPER DIFFLUENT ZONE TO THE E OF ANDREA...BETWEEN THE STORM'S EMBEDDED TROUGH AND RIDGING TO THE E...IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS BETWEEN 61W-73W. FARTHER E...A SFC TROUGH EXTENDS SW FROM A WEAK 1018MB NEAR 31N41W TO 27N47W. ISOLATED SHOWERS POSSIBLE WITHIN 90NM EITHER SIDE OF THE TROUGH. AN UPPER LOW IS MOVING S OF THESE SFC FEATURES NEAR 26N45W. THE SRN PERIPHERY OF HIGH PRES W OF PORTUGAL DOMINATES THE E ATLC AREA E OF 40W. UW-CIMMS SAHARAN AIR ANALYSIS DEPICTS A FAIRLY DENSE AREA OF DUST E OF ABOUT 30W. THIS VERY DRY AIR HAS CLEARED MOST OF THE LOW TO MID LEVEL CLOUDS IN THE ERN-MOST ATLC. $$ WILLIS