000 AXNT20 KNHC 031751 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN OCT 03 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 1715 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 06N30W TO 14N28W MOVING W AT 10 KT. THIS WAVE HAS BEEN TRACKED SINCE EMERGING OFF THE W AFRICA COAST AND REMAINS A RELATIVELY WEAK PERTURBATION EMBEDDED WITHIN THE ITCZ. THE WAVE AXIS IS COLLOCATED WITH A MAXIMUM IN TOTAL PRECIPITABLE WATER FROM 08N-15N BETWEEN 22W-31W. AN INVERTED-V CLOUD PATTERN IS EVIDENT IN VISIBLE SATELLITE IMAGERY WITH NO SIGNIFICANT CONVECTION ACCOMPANYING THE WAVE AT THIS TIME. TROPICAL WAVE EXTENDS ALONG 20N61W 15N64W TO 11N67W MOVING W AT 10-15 KT. A BROAD AND ILL-DEFINED 1008 MB LOW CENTER IS ANALYZED ALONG THE WAVE AXIS NEAR 17N63W. WHILE A BROAD CYCLONIC CIRCULATION EXISTS OVER A LARGE PORTION OF THE EASTERN CARIBBEAN SEA...LOW-LEVEL CONVERGENCE IS MAXIMIZED EAST OF THE LESSER ANTILLES PRODUCING NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION FROM 12N-20N BETWEEN 55W-61W. THIS CONVECTIVE ACTIVITY FALLS UNDER AN UPPER LEVEL DIFFLUENT ENVIRONMENT LOCATED SOUTH OF AN UPPER LEVEL TROUGH WITH AXIS ALONG 20N AND WITHIN THE SE PERIPHERY OF AN UPPER LEVEL RIDGE COVERING MUCH OF THE CARIBBEAN SEA. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS ELSEWHERE IN THE VICINITY OF THE WAVE AXIS FROM 11N-20N BETWEEN 61W-68W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 07N11W 05N21W 08N30W 10N40W 07N45W 06N49W 09N61W. ASIDE FROM THE TROPICAL WAVE ALONG 30W...A PAIR OF SURFACE TROUGHS ARE EMBEDDED WITHIN THE ITCZ. ONE IS ANALYZED FROM 03N-09N ALONG 21W AND EXHIBITS A LOW-AMPLITUDE CYCLONIC PERTURBATION TO THE MEAN EASTERLY FLOW. ISOLATED MODERATE CONVECTION IS FROM 04N-09N BETWEEN 19W-23W. THE OTHER SURFACE TROUGH EXTENDS FROM 07N44W TO 12N40W WITH A 1011 MB LOW CENTERED ALONG THE TROUGH AXIS NEAR 10N42W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 150 NM OF A LINE FROM 12N38W TO 07N49W. ELSEWHERE ALONG THE ITCZ...SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 150 NM S OF THE AXIS BETWEEN 11W-16W AND FROM 07N-11N BETWEEN 32W-37W. ...DISCUSSION... GULF OF MEXICO... SOUTHWESTERLY UPPER LEVEL FLOW DOMINATES ACROSS THE GULF AND FLORIDA PENINSULA THIS AFTERNOON S-SE OF AN UPPER LEVEL TROUGH MOVING ACROSS THE EASTERN CONUS. WATER VAPOR IMAGERY DENOTES VERY DRY AND STABLE AIR ALOFT. AT THE SURFACE FURTHER SUPPORTING THE STABLE ENVIRONMENT ARE N-NE WINDS UP TO 20 KT AND OVERALL CLEAR SKIES. WITH THE UPPER LEVEL TROUGH PUSHING EASTWARD AND LOCATING ALONG THE EASTERN U.S. SEABOARD BY TUESDAY...A HIGH PRESSURE RIDGE IS FORECAST TO CONTINUE IMPACTING THE GULF WITH NE WINDS AND FAIR CONDITIONS THROUGH LATE WEDNESDAY. CARIBBEAN SEA... AN UPPER LEVEL RIDGE REMAINS DOMINATE ALOFT OVER MUCH OF THE CARIBBEAN SEA BASIN ANCHORED BY AN UPPER LEVEL ANTICYCLONE CENTERED IN THE SW NORTH ATLC NEAR 26N68W. OVER THE WESTERN CARIBBEAN...A SURFACE TROUGH EXTENDS FROM THE W ATLC ACROSS EASTERN CUBA ALONG 20N76W 15N77W 12N80W TO SE NICARAGUA NEAR 11N84W. THIS SURFACE TROUGH MAINLY DEFINES A WIND SHIFT OVER THE WESTERN CARIBBEAN WITH LOW-LEVEL CONVERGENCE IN THE VICINITY OF THE SURFACE TROUGH AXIS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 120 NM EITHER SIDE OF THE BOUNDARY N OF 15N AND S OF 15N BETWEEN 75W-85W. FARTHER EAST...A TROPICAL WAVE IS TRACKING WESTWARD BRINGING NUMEROUS SHOWERS AND SCATTERED TSTMS TO MUCH OF THE EASTERN CARIBBEAN E OF 68W...WITH MORE DETAILS LOCATED ABOVE. ATLANTIC OCEAN... SOUTHWESTERLY FLOW ALOFT DOMINATES OVER THE W ATLC BETWEEN AN UPPER LEVEL TROUGH OVER THE EASTERN CONUS AND AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 26N68W. DRY AIR ALOFT IS NOTED N OF A LINE FROM THE FLORIDA STRAITS TO 32N70W ON WATER VAPOR IMAGERY...HOWEVER...SURFACE TROUGHING IS LOCATED BETWEEN 74W-80W OVER THE W ATLC. A SURFACE TROUGH IS ANALYZED FROM 29N75W ACROSS THE CENTRAL BAHAMAS TO EASTERN CUBA NEAR 21N76W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 120 NM EITHER SIDE OF THE BOUNDARY. FARTHER NORTH NEAR THE TAIL END OF A FRONTAL BOUNDARY...A 1009 MB LOW IS CENTERED NEAR 30N79W WITH A SURFACE TROUGH EXTENDING SW TO THE FLORIDA COAST NEAR FORT PIERCE. POSSIBLE ISOLATED SHOWERS ARE N OF 30N BETWEEN 77W-80W. THE REMAINDER OF THE ATLC IS IMPACTED BY A SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED NEAR 36N47W. WHILE AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 36N46W SUPPORTS THE SURFACE RIDGE OVERALL...AN UPPER LEVEL LOW IS CENTERED NEAR 25N36W AND EXTENDS AN UPPER LEVEL TROUGH AXIS FROM THE LOW WSW TO NEAR 20N57W. THIS UPPER LEVEL FEATURES IS PROVIDING ENOUGH ATMOSPHERIC INSTABILITY AND LIFT TO GENERATE SCATTERED SHOWERS AND TSTMS FROM 15N-21N BETWEEN 41W-60W. THE CONVECTIVE ACTIVITY W OF 55W IS LARGELY ASSOCIATED WITH THE TROPICAL WAVE MENTIONED ABOVE IMPACTING THE EASTERN CARIBBEAN SEA AND LESSER ANTILLES. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN