000 AXNT20 KNHC 141746 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED OCT 14 2009 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 IS ALONG 61W S OF 15N MOVING W NEAR 15 KT. THE WAVE REMAINS EMBEDDED WITHIN AN AREA OF DEEP MOISTURE ACROSS THE WINDWARD ISLANDS AND PORTIONS OF THE SE CARIBBEAN AS INDICATED IN THE TOTAL PRECIPITABLE WATER IMAGERY. VISIBLE SATELLITE IMAGERY SHOWS CYCLONIC CURVATURE IN THE LOW-LEVEL CLOUD FIELD IN THE VICINITY OF THE WAVE AXIS. AS IT CONTINUES MOVING WWD INTO THE SE CARIBBEAN AND A DRIER AND MORE STABLE ENVIRONMENT ALOFT...ONLY A FEW ISOLATED SHOWERS ARE NOTED FROM 11N-14N BETWEEN 60W-63W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N15W 8N28W 8N31W 9N48W 9N50W. ONE SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ ALONG 29W FROM 5N-11N. SCATTERED TO NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION IS FROM 5N-12N BETWEEN 18W-34W. THIS ACTIVITY IS LIKELY ENHANCED DUE TO AN UPPER LEVEL DIFFLUENT PATTERN ACROSS THE ERN TROPICAL ATLC BETWEEN UPPER LEVEL TROUGHING N OF 13N AND A BROAD UPPER LEVEL RIDGE OVER W AFRICA. A SECOND SURFACE TROUGH...ALSO EMBEDDED WITHIN THE ITCZ...IS ANALYZED ALONG 49W FROM 6N-14N. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 5N-11N BETWEEN 46W-53W. ...DISCUSSION... GULF OF MEXICO... A BROAD E-W ORIENTED UPPER LEVEL RIDGE EXTENDS ALONG 25N FROM THE W ATLC...OVER THE FLORIDA PENINSULA...GULF OF MEXICO AND ACROSS NRN MEXICO. AN UPPER LEVEL TROUGH CONTINUES PROGRESSING OVER THE LOWER MISSISSIPPI RIVER VALLEY AND EXTENDS TROUGHING ACROSS THE NW PORTION OF THE GULF. UPPER LEVEL DIFFLUENCE BETWEEN THESE TWO UPPER LEVEL FEATURES IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE NE GULF N OF 27W E OF 91W. ELSEWHERE S OF 25N AND THE UPPER LEVEL RIDGE...DRY ELY FLOW ALOFT COUPLED WITH A WEAK SURFACE PRESSURE GRADIENT IS PROVIDING THE SRN GULF WITH GENERALLY CLEAR SKIES AND LIGHT E-SE WINDS. CARIBBEAN SEA... THE UPPER LEVEL ANTICYCLONIC CIRCULATION WITH AXIS ALONG 25N OVER THE W ATLC AND GULF OF MEXICO IS PROVIDING MOST OF THE CARIBBEAN WITH E-NE WINDS ALOFT N OF A SHEAR AXIS EXTENDING FROM THE LESSER ANTILLES TO THE COAST OF NRN COLOMBIA NEAR 11N74W. WATER VAPOR IMAGERY INDICATES AN OVERALL DRY AND STABLE ATMOSPHERE IN THE MIDDLE TO UPPER LEVELS ACROSS THE ENTIRE BASIN WITH ONLY A FEW AREAS OF ISOLATED SHOWERS MOVING WWD ON MODERATE TRADE WINDS. A CONCENTRATED AREA OF THESE SHOWERS ARE FROM 16N-19N BETWEEN 75W-83W. IN THE SW CARIBBEAN...THE ITCZ AXIS EXTENDS ALONG 9N ACROSS COSTA RICA AND PANAMA. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING S OF 11N. ATLANTIC OCEAN... A COLD FRONT ENTERS THE DISCUSSION AREA NEAR 32N60W AND EXTENDS SW ALONG 28N69W TO 28N78W. THE UPPER LEVEL TROUGH SUPPORTING THIS FRONT IS QUICKLY MOVING EWD ACROSS THE NRN CENTRAL ATLC WELL NORTH OF THE AREA. THE FRONT IS FORECAST TO GRADUALLY DISSIPATE AND MERGE WITH A SECONDARY REINFORCING COLD FRONT THAT ENTERS THE REGION NEAR 32N65W AND EXTENDS WWD ALONG 31N TO 80W. ISOLATED SHOWERS ARE OCCURRING WITHIN 60 NM EITHER SIDE OF THE SOUTHERNMOST FRONT. FARTHER E ACROSS THE ERN ATLC...A 1012 MB SURFACE LOW IS CENTERED NEAR 29N32W WITH A SURFACE TROUGH EXTENDING FROM 29N31W ALONG 25N34W TO 24N40W. ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE OF THE SURFACE TROUGH WITH SCATTERED SHOWERS LOCATED E OF THE LOW COVERING AN AREA FROM 26N-31N BETWEEN 23W-30W. THIS SURFACE LOW IS EMBEDDED BENEATH AN UPPER LEVEL TROUGH AXIS ALONG 27W. $$ HUFFMAN