000 AXNT20 KNHC 170005 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU AUG 16 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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. ...SPECIAL FEATURES... TROPICAL DEPRESSION ERIN CONTINUES TO WEAKEN AND MOVE FARTHER INLAND OVER SOUTH TEXAS. ERIN IS PRODUCING HEAVY RAINS ACROSS SOUTH-CENTRAL AND SOUTHEAST TEXAS. FURTHER INFORMATION ON THIS SYSTEM CAN BE FOUND IN PUBLIC ADVISORIES ISSUED BY THE HYDROMETEOROLOGICAL PREDICTION CENTER...UNDER AWIPS HEADER TCPAT5 AND WMO HEADER WTNT35 KWNH. THE CENTER OF HURRICANE DEAN AT 17/0000 UTC WAS NEAR 14.0N 57.8W OR ABOUT 175 NM/330 KM EAST OF MARTINIQUE. DEAN IS MOVING WEST 20 KT. THE MAXIMUM SUSTAINED WIND SPEEDS ARE NEAR 85 KT WITH GUSTS TO 100 KT...WHICH MAKES DEAN A CATEGORY TWO HURRICANE. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 979 MB. SOME STRENGTHENING IS FORECAST BEFORE THE HURRICANE REACHES THE LESSER ANTILLES EARLY FRIDAY. OUTER RAINBANDS OF DEAN ARE MOVING THROUGH THE WINDWARD ISLANDS. STORM TOTAL RAINFALLS OF 2 TO 5 INCHES...WITH ISOLATED MAXIMUM AMOUNTS OF 7 INCHES IN MOUNTAINOUS AREAS...ARE POSSIBLE IN ASSOCIATION WITH DEAN. THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUDSLIDES. PLEASE SEE THE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC OR THE LATEST PUBLIC ADVISORY UNDER MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. NUMEROUS MODERATE TO STRONG CONVECTION IS CURRENTLY FROM 10N-16N BETWEEN 54W-62W...BUT THIS AREA IS MOVING W FAIRLY RAPIDLY. ...TROPICAL WAVES... TROPICAL WAVE PREVIOUSLY OFF THE AFRICAN COAST ALONG 17W WAS ADJUSTED TO 24W S OF 20N DUE TO THE PRESENCE OF THE BROAD REGION OF LOW TO MID LEVEL CYCLONIC TURNING IN THE VICINITY. THE WAVE APPEARS TO BE MOVING FAIRLY QUICKLY W 15-20 KT. DEEP CONVECTION IS MINIMAL. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 37W/38W SOUTH OF 20N MOVING W 15-20 KT. THIS WAVE CONTINUES TO EXHIBIT CYCLONIC TURNING IN THE SURROUNDING LOW AND MID LEVEL CLOUDS. HOWEVER...THE OVERALL ENVELOPE OF THE WAVE APPEARS SMALLER THAN IT WAS LAST NIGHT...AND ALSO SHIFTED MORE SW THAN IT HAS BEEN. A FEW SMALL CLUSTERS OF MODERATE CONVECTION ARE FROM 12N-14N BETWEEN 37W-40W. A TROPICAL WAVE IS ALONG 69W SOUTH OF 18N MOVING WEST NEAR 20 KT. AN INVERTED V PATTERN REMAINS EVIDENT WITH THIS WAVE...WHICH ALSO SHOWS UP WELL AS A WWD SURGE OF MOISTURE IN THE UW-CIMSS TPW PRODUCT. SHOWER AND TSTM ACTIVITY REMAINS MINIMAL OVER THE CARIBBEAN PORTION OF THE WAVE...THOUGH A SURGE OF SCATTERED MODERATE CONVECTION IS NOTED INLAND OVER WRN VENEZUELA AND ERN COLOMBIA. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N15W 11N27W 10N35W 9N42W 14N50W. SCATTERED MODERATE CONVECTION IS S OF THE AXIS FROM 7N-11N E OF 26W. SIMILAR CLUSTERS OF MOVING OFF THE AFRICAN COAST FROM 11N-16N E OF 19W. SCATTERED MODERATE ALSO WITHIN 150NM S OF THE AXIS BETWEEN 39W-45W. DISCUSSION... THE GULF OF MEXICO... TROPICAL DEPRESSION ERIN HAS MOVED INLAND OVER SOUTH TEXAS AS DESCRIBED ABOVE. HOWEVER...A TAIL OF MOISTURE LEFT BEHIND THE SYSTEM IS PRODUCING NUMEROUS SHOWERS AND TSTMS IN THE NW GULF...N OF 13N BETWEEN 92W-97W. THE E GULF IS OVERALL MUCH QUIETER THOUGH A FEW ISOLATE SHOWERS/TSTMS EXIST ESPECIALLY FROM 23N-29N E OF 91W. AN UPPER HIGH IS NEAR THE TEXAS/LOUISIANA BORDER WHILE WEAK INVERTED UPPER TROUGHING EXTENDS NW FROM THE YUCATAN CHANNEL. DIFFLUENCE ALOFT BETWEEN THESE FEATURES IS ALSO SUPPORTING THE AFOREMENTIONED CONVECTION. ELSEWHERE AT THE SFC RIDGING IS BUILDING INTO THE N GULF BEHIND ERIN AND LOOKS TO BE THE DOMINANT FEATURE OVER THE NEXT COUPLE OF DAYS. HURRICANE DEAN EXPECTED TO BECOME AN ISSUE BY EARLY NEXT WEEK BUT UNCERTAINTIES STILL EXIST IN THE SPECIFICS. THE CARIBBEAN SEA... HURRICANE DEAN CONTINUES TO RAPIDLY APPROACH THE LESSER ANTILLES WITH THE ASSOCIATED CONVECTION NOW AFFECTING THE FAR SE CARIBBEAN. OTHERWISE ONLY A FEW ISOLATED CELLS OF MODERATE CONVECTION ARE AFFECTING THE BASIN. DEAN WILL HAVE SIGNIFICANT IMPACTS ON THE CARIBBEAN OVER THE NEXT FEW DAYS...DETAILS CAN BE FOUND ABOVE IN THE SPECIAL FEATURES SECTION. N TO NE UPPER FLOW CONTINUES TO BLOW OVER THE NW CARIBBEAN...WHILE CYCLONIC FLOW IS OVER THE CENTRAL PORTION S OF AN UPPER LOW NE OF THE BAHAMAS. UPPER RIDGING FROM THE ATLC IS AFFECTING THE NE CARIB. ASIDE FROM DEAN AND THE TROPICAL WAVE S OF HISPANIOLA...TRADES ARE CURRENTLY MODERATE TO FRESH BUT WINDS AND SEAS WILL INCREASE RAPIDLY IN THE ERN PORTION THROUGH FRI. THE ATLANTIC OCEAN... THE DOMINANT FEATURE IN THE WRN ATLC IS THE UPPER LOW NE OF THE BAHAMAS NEAR 27N75W. THIS HAS BEEN GENERATING A FEW ISOLATED TSTMS BETWEEN 66W-76W BUT OVERALL THE WRN ATLC IS QUIET. THE UPPER LOW IS FORECAST TO MOVE W INTO THE GULF THIS WEEKEND WHILE DEEP LAYER RIDGING REMAINS N OF DEAN...KEEPING IT ON A WWD TRACK. A REMNANT FRONTAL TROUGH IS ALONG 32N72W 27N77W...BUT THIS IS EXPECTED TO CONTINUE DISSIPATING THROUGH FRI AS LARGER SCALE SFC RIDGING BUILDS W. ANOTHER UPPER LOW IS NOTED NEAR 28N47W BUT ONLY APPEARS TO BE GENERATING PATCHES OF CIRRUS. LARGE SCALE UPPER RIDGING EXTENDS W FROM AFRICA OUT TO 30W. THE REMAINDER OF THE SFC PATTERN ON THE LARGE SCALE IS DOMINATED BY THE SRN PERIPHERY OF A 1030 MB HIGH NEAR 42N23W...WHICH IS PRODUCING MODERATE TRADES AND ABUNDANT FAIR WEATHER N OF 20N E OF 60W. $$ WILLIS