000 AXNT20 KNHC 081804 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED SEP 08 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...SPECIAL FEATURES... TROPICAL STORM IGOR WAS UPDATED AT 08/1500 UTC. THE LATEST ADVISORY AT 1800 UTC PLACES IGOR NEAR 13.7N 23.7W...OR ABOUT 80 MI S OF PRAIA IN THE CAPE VERDE ISLANDS. THIS SYSTEM IS MOVING MOVING W AT 5 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. PLEASE SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT5/WTNT35 KNHC AND THE FULL FORECAST AND ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. THIS SYSTEM IS EMBEDDED WITHIN AN AREA OF DEEP LEVEL MOISTURE AS INDICATED ON TOTAL PRECIPITABLE WATER IMAGERY. BROAD AND ELONGATED SURFACE CYCLONIC FLOW SURROUNDS IGOR AND TWO MORE SURFACE LOW PRESSURE SYSTEMS. IGOR AND THE CLOSEST SURFACE LOW TO THE NE OF IT ARE GENERATING SCATTERED MODERATE TO STRONG CONVECTION FROM 12N TO 20N BETWEEN 17W AND 28W. ...TROPICAL WAVES... NO TROPICAL WAVES ARE OBSERVED OVER THE ATLANTIC. ...ITCZ... THE ITCZ AXIS IS ANALYZED FROM 7N35W CONTINUING WESTWARD ALONG 8N46W 10N60W TO A SURFACE TROUGH ANALYZED FROM 14N59W TO 6N62W. SCATTERED WEAK TO MODERATE CONVECTION IS WITHIN 50 NM ON EITHER SIDE OF THE ITCZ AXIS...WHILE THE SURFACE TROUGH IS GENERATING MODERATE TO ISOLATED STRONG CONVECTION S OF 14N W OF 66W INCLUDING NORTHERN PORTIONS OF EASTERN VENEZUELA AND GUYANA. ...DISCUSSION... GULF OF MEXICO... THE MOISTURE AND INSTABILITY ASSOCIATED TO HERMINE HAS MOVED NORTH OUT OF THE GULF INTO TEXAS AND OKLAHOMA REGION. NOW...A DRY AND STABLE AIRMASS ALOFT HAS MOVED ACROSS THE GULF W OF 86W...PROVIDING OVERALL FAIR WEATHER CONDITIONS ACROSS MOST OF THE REGION...EXCEPT FOR THE SW BASIN...WHERE AN ELONGATED UPPER LEVEL LOW/TROUGH...CURRENTLY OVER THE NW CARIBBEAN...IS ENHANCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE FLORIDA STRAITS AND SE GULF S OF 27N E OF 86W. THIS UPPER LEVEL LOW WILL CONTINUE TO MOVE WNW GENERATING CONVECTION IN THE EASTERN AND CENTRAL REGIONS OF THE GULF OVER THE NEXT 24 TO 48 HRS...WITH THE STRONGEST CONVECTION ACROSS THE FLORIDA STRAITS. CARIBBEAN SEA... THE VIGOROUS REMNANT SURFACE TROUGH OF GASTON IS MOVING ACROSS THE NORTH CENTRAL CARIBBEAN ANALYZED ALONG 70W FROM 15N TO 20N. SCATTERED MODERATE TO STRONG CONVECTION GENERATED FROM THIS SYSTEM COVERS THE AREA N OF 15N BETWEEN 68W AND 75W. MODEL GUIDANCE SUGGEST THE LOW LEVEL CIRCULATION OF GASTON COULD REAPPEAR OVER OVER THE NEXT 24 HOURS AS IT MOVES WESTWARD ACROSS THE N CARIBBEAN. WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW OVER THE NW CARIBBEAN SPINNING NEAR 21N81W. THIS FEATURE IS ENHANCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE YUCATAN CHANNEL. SATELLITE IMAGERY LOOP FROM A FEW DAYS AGO TO MOST RECENT IMAGE IS SHOWING THE MONSOONAL TROUGH...CURRENTLY OVER NORTHERN SOUTH AMERICA...SPREADING NORTHWARD INTO THE SOUTH CARIBBEAN...GENERATING SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ACROSS THE SOUTHERN CARIBBEAN S OF 15N. LONG RANGE COMPUTER MODELS INDICATE THIS AREA OF CONVECTION WILL LINGER IN THIS REGION AND BECOME MORE ACTIVE OVER THE NEXT FEW DAYS...ALSO HINTING AT THE POSSIBILITY OF A LOW PRESSURE SYSTEM DEVELOPING OVER THE FAR SE BASIN OVER THE FORECAST PERIOD. ATLANTIC OCEAN... THE PRIMARY CONCERN HAS TURNED TO THE EASTERN ATLC...AS TROPICAL STORM IGOR WAS UPDATED AT 08/1500 UTC...CURRENTLY SOUTH OF THE CAPE VERDE ISLANDS. FOR MORE DETAILS REGARDING THIS NEWLY NAMED STORM...SEE SPECIAL FEATURES ABOVE. BROAD AND ELONGATED SURFACE CYCLONIC CIRCULATION SURROUNDS IGOR AND TWO MORE SURFACE LOW PRESSURE SYSTEMS...A 1010 MB NEAR 20N36W AND A 1008 MB EAST OF CAPE VERDE ISLANDS NEAR 16N21W. IGOR AND THE SURFACE LOW EAST OF CAPE VERDE ISLANDS ARE GENERATING SCATTERED MODERATE TO STRONG CONVECTION FROM 12N TO 20N BETWEEN 17W AND 28W. THE OTHER SURFACE LOW IS ONLY GENERATING SCATTERED WEAK CONVECTION WITHIN A 300 NM RADIUS. AN ELONGATED UPPER LEVEL LOW/TROUGH...CURRENTLY OVER THE NW CARIBBEAN AND THE REMNANT SURFACE TROUGH OF GASTON OVER THE NORTH CENTRAL CARIBBEAN...ARE ENHANCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE SW ATLC BASIN S OF 25N W OF 70W...INCLUDING THE NORTHERN COASTAL WATERS OF CUBA...THE BAHAMAS S OF 25N AND ACROSS THE FLORIDA STRAITS. COMPUTER MODELS SUGGEST THE CONVECTION IN THIS AREA WILL CONTINUE OVER THE NEXT 24 TO 48 HOURS. ELSEWHERE ACROSS THE DISCUSSION AREA...BROAD MID/UPPER LEVEL SUB-TROPICAL RIDGES DOMINATE THE ATLC AND SUPPORT THE WESTERN ATLC SURFACE 1020 MB HIGH NEAR 30N70W...AND THE EASTERN ATLC SURFACE 1023 MB HIGH NEAR 36N25W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA