000 AXNT20 KNHC 240003 TWDAT TROPICAL WEATHER DISCUSSION... NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT JUN 23 2012 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...SPECIAL FEATURES... THE BROAD ELONGATED LOW PRESSURE SYSTEM OVER THE ERN GULF BECAME TROPICAL STORM DEBBY AT 23/2100 UTC...WITH THE LATEST POSITION CENTERED NEAR 26.1N 87.5W. THIS LOCATION IS ABOUT 220 MI SSE OF THE MOUTH OF THE MISSISSIPPI RIVER. DEBBY IS CURRENTLY NEAR STATIONARY WITH MAXIMUM SUSTAINED WINDS OF 45 KT WITH GUSTS TO 55 KT. MINIMUM CENTRAL PRESSURE IS 1000 MB. THIS SYSTEM IS GENERATING A BROAD AREA OF SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS ACROSS THE ERN GULF WATERS E OF 87W S OF 30N. SEAS 12 FT OR GREATER ARE WITHIN 210 NM OVER THE NE QUADRANT AND 150 NM OVER THE SE QUADRANT WITH SEAS TO 15 FT. INTERESTS IN THIS AREAS SHOULD CONTINUE TO MONITOR THE PROGRESS OF THIS SYSTEM. HEAVY RAINS AND LOCALIZED FLOODING ARE POSSIBLE ACROSS WESTERN CUBA AND MUCH OF FLORIDA OVER THE NEXT DAY OR SO. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE MOVES ACROSS THE CENTRAL ATLC TROPICAL WATERS EXTENDING FROM 16N40W TO 10N41W MOVING W AT 10-15 KT. THE WAVE PRECEDES A SURGE OF DEEP MOISTURE ON TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...NO SIGNIFICANT CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME...DUE TO SAHARAN DUST COVERING MUCH OF THE TROPICAL NORTH ATLC WATERS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE WESTERN AFRICAN COAST OF MAURITANIA NEAR 17N16W ALONG 10N22W TO 5N34W...WHERE THE ITCZ BEGINS AND CONTINUES WNW TO NEAR 7N43W. CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE FROM 3N-8N BETWEEN THE COAST OF WEST AFRICA AND 35W...AND WITHIN 70-120 NM ON EITHER SIDE OF THE ITCZ BETWEEN 35W-44W. ...DISCUSSION... GULF OF MEXICO... THE ATTENTION THIS EVENING HAS TURNED TO NEW DEVELOPED TROPICAL STORM DEBBY LOCATED NEAR 26.2N 87.6W AT 23/2100 UTC. FOR MORE DETAILS...SEE SPECIAL FEATURE ABOVE. THE CIRCULATION ASSOCIATED TO THIS SYSTEM IS VERY BROAD AND COVERS THE ENTIRE GULF...THE NW CARIBBEAN AND THE FAR WEST ATLC. TO DEPICT THE COVERAGE OF THE CIRCULATION...A SURFACE TROUGH IS ANALYZED FROM THE FLORIDA PANHANDLE NEAR 30N85W TO JUST N OF THE CENTER OF DEBBY NEAR 28N87W...AND ANOTHER SURFACE TROUGH FROM JUST S OF THE CENTER NEAR 24N87W CONTINUING INTO THE YUCATAN PENINSULA ALONG 21N89W. THIS SYSTEM IS GENERATING A BROAD AREA OF SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS ACROSS THE ERN GULF WATERS E OF 87W S OF 30N...AS WELL AS INLAND PORTIONS OF THE FLORIDA PENINSULA. THERE ARE A FEW CLUSTERS OF SIMILAR CONVECTION IN THE BAY OF CAMPECHE. OTHERWISE...AN UPPER LEVEL LOW IS SITTING OVER THE NW BASIN NEAR 28N93W. HOWEVER THE ACTIVITY ASSOCIATED TO THIS FEATURE IS MINIMAL DUE TO DRY AIR INTRUSION NOTED ON WATER VAPOR IMAGERY. CARIBBEAN SEA... GUSTY SOUTHERLY WINDS UP TO 30 KT...SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS REMAIN OVER THE NW CARIBBEAN WATERS N OF 18N W OF 78W...ASSOCIATED TO THE BROAD SURFACE CYCLONIC WIND FIELD FROM TROPICAL STORM DEBBY. PERSISTENT CONVECTION IS FORECAST TO CONTINUE ACROSS THE FAR NW CARIBBEAN DURING THE NEXT DAY OR SO. LOCALLY HEAVY RAINFALL WITH THE HIGH POTENTIAL FOR FLOODING AND MUDSLIDES IS LIKELY OVER PORTIONS OF WESTERN CUBA AND THE YUCATAN PENINSULA DURING THE NEXT DAY OR SO. OTHERWISE ...FAIR WEATHER CONDITIONS ARE ACROSS THE REMAINDER OF THE CARIBBEAN THIS EVENING DUE TO DRY AIR ALOFT AROUND AN UPPER LEVEL RIDGE COVERING THE WRN CARIBBEAN. THE FAIR WEATHER IS ESPECIALLY NOTED OVER THE EASTERN BASIN DUE TO SAHARAN DUST ACROSS THIS REGION. IMPACTS WILL CONTINUE TO BE HAZY SKY CONDITIONS OVER THE NEXT FEW DAYS. ATLANTIC OCEAN... SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS COVER THE FAR WRN ATLC W OF 73W...INCLUDING THE BAHAMAS...NORTHERN COASTAL WATERS OF CUBA...AND THE STRAITS OF FLORIDA. THIS REGION OF CONVECTION IS ASSOCIATED TO THE BROAD CYCLONIC CIRCULATION OF TROPICAL STORM DEBBY. TO THE EAST OF THIS AREA....WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW SPINNING NEAR 29N65W. HOWEVER ...THE CONVECTION ASSOCIATED TO THIS SYSTEM IS WEAK AND LIMITED DUE TO INTRUSION OF DRY AIR AROUND THE UPPER LOW. AN UPPER LEVEL TROUGH OVER THE CENTRAL N ATLC SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 31N45W TO 29N56W. ISOLATED WEAK SHOWERS ARE ALONG THE AXIS. A PRE-FRONTAL SURFACE TROUGH IS ALONG 31N42W TO 26N51W GENERATING SIMILAR CONVECTION WITHIN 90 NM E OF THE AXIS. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC BASINS ARE UNDER THE INFLUENCE OF A SURFACE RIDGE AXIS EXTENDING WSW ACROSS THE DISCUSSION AREA ANCHORED BY A 1028 MB HIGH NEAR 37N20W. THE FAIR WEATHER CONDITIONS OVER THE ERN ATLC ARE FURTHER ENHANCED BY SAHARAN DUST DEPICTED ON THE METEOSAT-9 SAHARAN AIR LAYER TRACKING PRODUCT. THIS AREA OF SAHARAN DUST EXTENDS FROM THE COAST OF AFRICA ALL THE WAY TO THE ERN CARIBBEAN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA