000 AXNT20 KNHC 090555 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST FRI MAR 09 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 0500 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N12W 5N20W 3N35W 1N47W TO 1S51W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 20W-27W. SCATTERED SHOWERS AND TSTMS LIE FROM 1S-1N BETWEEN 38W-41W. ...DISCUSSION... GULF OF MEXICO... IT'S ANOTHER RELATIVELY QUIET NIGHT IN THE GULF AS WEAK VERTICALLY STACKED RIDGING REMAINS PARKED ACROSS THE REGION. UPPER LEVEL SWLY FLOW ON THE WRN PERIPHERY OF THE RIDGE IS ADVECTING HIGH LEVEL MOISTURE FROM THE EPAC ACROSS CENTRAL MEXICO AND INTO THE GULF MAINLY BETWEEN 24N-29N. WHILE THE ATMOSPHERE IS A LITTLE MORE MOIST THAN PAST FEW DAYS ...CONDITIONS REMAIN FAIR ACROSS THE ENTIRE AREA. MODERATE DRY AIR EXISTS S OF THE UPPER MOISTURE PLUME OVER THE BAY OF CAMPECHE. THE WEAK PATTERN AT THE SFC IS KEEPING WINDS AND SEAS FAIRLY LIGHT AND THEY ARE EXPECTED TO REMAIN THAT WAY THROUGH SAT AS THE SFC PRES GRADIENT CHANGES LITTLE. MAINLY FAIR WEATHER IS ALSO EXPECTED TO CONTINUE. THE ONLY AREA OF POSSIBLE WEATHER IS IN THE CENTRAL GULF AS GFS HAS BEEN HINTING AT DEVELOPING A WEAK SFC TROUGH LATER TODAY THAT MAY PRODUCE SOME CLOUDS/SHOWERS. CARIBBEAN... MUCH OF THE CARIB IS PRETTY QUIET THIS LATE EVENING WITH PLENTY OF DRY STABLE AIR ALOFT IN PLACE. THIS DRY AIR IS BEING ENHANCED BY A SHORTWAVE TROUGH THAT EXTENDS SWD FROM THE ATLC ACROSS HISPANIOLA TO 14N74W. THERE IS A FAIR AMOUNT OF MID TO UPPER LEVEL MOISTURE AND EVEN SOME SMALL POCKETS OF MODERATE CONVECTION OVER COLOMBIA PRODUCED BY UPPER DIFFLUENCE BETWEEN THE SHORTWAVE AND A STRONG UPPER RIDGE CENTERED OVER NE S AMERICA. MOST OF THIS MOISTURE IS CONTAINED S OF 13N. IN THE LOWER LEVELS...NIGHT CHANNEL VIS SHOWS VERY THIN PATCHES OF CLOUDS DRIVEN W BY MODERATE TO FRESH TRADES. THERE IS A LITTLE MORE ORGANIZATION TO THE CLOUDS OVER THE YUCATAN PENINSULA AND THE CHANNEL ASSOCIATED WITH THE REMNANTS OF A WEAK SFC TROUGH. MUCH MORE ACTIVE WEATHER LIES TO THE N OF THE REGION E OF THE BAHAMAS AND IS DISCUSSED IN THE WESTERN ATLC SECTION. TRANQUIL WEATHER IS EXPECTED TO CONTINUE INTO THE WEEKEND. WESTERN ATLANTIC... UNLIKE THE GULF AND CARIB THERE IS SOME WEATHER TO TALK ABOUT IN THIS REGION. THE MAIN PLAYERS ARE AN UPPER LEVEL SHORTWAVE TROUGH ROTATING THROUGH A LARGE POLAR VORTEX AND A SFC TROUGH ANALYZED FROM ERN CUBA TO 29N66W. A WEAK SFC LOW APPEARS TO HAVE FORMED ALONG THIS TROUGH NEAR 24N73W. THIS FEATURE IS WELL DEPICTED IN AN EARLIER QSCAT PASS AND SFC OBS WHICH DISPLAY CYCLONIC TURNING ESPECIALLY ACROSS THE SE BAHAMAS. INFRARED SATELLITE IMAGES DEPICT SOME COLD CLOUD TOPS FROM 23N-31N BETWEEN 52W-72W. SCATTERED SHOWERS APPEAR VERY LIKELY IN THIS OUTLINED AREA ESPECIALLY E OF THE SFC TROUGH DUE TO THE SHEARED ENVIRONMENT. THIS UNSETTLED WEATHER MAY ALSO BE ENHANCED BY A DISSIPATING STATIONARY BOUNDARY WHICH EXTENDS ALONG 32N47W 28N55W. ANOTHER COLD FRONT IS LINED UP BEHIND THE TROUGH ENTERING THE AREA NEAR 32N67W TO THE SE GEORGIA COAST. GFS SHOWS THIS FRONT MERGING WITH THE TROUGH/LOW LATER TODAY LIKELY CONTINUING TO PRODUCE UNSETTLED WEATHER FOR PARTS OF THE REGION. STRONG HIGH PRES IS DIGGING SE BEHIND THE FRONT STRENGTHENING THE WINDS. EASTERN ATLANTIC... A STRONG 1036 MB HIGH PRES SYSTEM LOCATED BETWEEN PORTUGAL AND THE AZORES IS DOMINATING THE SFC PATTERN ACROSS THE ATLC E OF 45W. THIS HIGH IS PRODUCING MODERATE TO STRONG TRADE WINDS ACROSS A GOOD PORTION OF THE DISCUSSION AREA PARTICULARLY E OF 30W WHERE THE TIGHTEST PRES GRAD EXISTS. THE UPPER LEVEL TROUGH THAT HAS BEEN DRIFTING N IN THE AREA HAS NOW JUST ABOUT DISSIPATED. ONLY PATCHES OF MID AND HIGH LEVEL CLOUDS ARE LEFT N OF 21N BETWEEN 20W-30W. ELSEWHERE DRY AIR ALOFT DOMINATES PROVIDING STABLE CONDITIONS. OVER THE NEXT COUPLE OF DAYS...THE STRONG SFC HIGH IS FORECAST TO RETREAT NE ALLOWING THE TRADES TO RELAX SLIGHTLY THIS WEEKEND IN THE E ATLC. HOWEVER THEY ARE SET TO PICK UP AGAIN ON SUN AND INTO NEXT WEEK AS STRONG HIGH PRES BUILDS E ACROSS THE ATLC. $$ CANGIALOSI