000 AXNT20 KNHC 152347 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE SEP 15 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 74W S OF 18N MOVING W NEAR 20 KT. THIS WAVE CONTINUES MOVING BENEATH DRY NELY UPPER LEVEL FLOW WHICH IS INHIBITING ANY SIGNIFICANT DEEP CONVECTION ACROSS THE CENTRAL CARIBBEAN...THUS ONLY ISOLATED SHOWERS ARE LOCATED MAINLY S OF JAMAICA FROM 14N-18N BETWEEN 75W-80W. ...ITCZ... THE ITCZ AXIS IS ALONG 9N13W 10N27W 9N40W 8N60W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALONG THE W AFRICA COAST AND WITHIN 60 NM OFFSHORE FROM 8N-14N E OF A LINE FROM 8N14W TO 14N19W. SCATTERED MODERATE CONVECTION IS FROM 5N-10N BETWEEN 19W-26W AND FROM 5N-9N BETWEEN 30W-35W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL SHORTWAVE TROUGH IS ACROSS ERN TEXAS AND SUPPORTS A 1008 MB SURFACE LOW CENTERED OVER NE LOUISIANA NEAR 33N92W. A COLD FRONT EXTENDS S FROM THE LOW TO THE GULF COAST NEAR CAILLOU BAY AND INTO THE NW GULF AS A STATIONARY FRONT ALONG 29N91W 24N97W. VERY DRY SWLY FLOW ALOFT IS INHIBITING MOST CONVECTION ALONG THIS FRONT...HOWEVER...SCATTERED SHOWERS ARE FROM 26N28N BETWEEN 90W-92W AND ARE MOVING ENE. A SURFACE TROUGH IS ANALYZED OVER THE WRN YUCATAN PENINSULA AND WRN GUATEMALA. THIS SURFACE FEATURE ALONG WITH AN UPPER LEVEL DIFFLUENT PATTERN ACROSS SRN MEXICO IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS SW OF A LINE FROM 19N92W TO 22N96W OVER THE WRN BAY OF CAMPECHE. A LARGE AREA OF UPPER DIFFLUENCE ON THE NRN PERIPHERY OF AN ANTICYCLONIC CIRCULATION CENTERED OVER WRN CUBA IS GENERATING SCATTERED SHOWERS AND TSTMS N OF 24N E OF 86W. THIS ACTIVITY SPREADS ACROSS A MAJORITY OF THE WRN FLORIDA PENINSULA THIS EVENING. CARIBBEAN SEA... TWO UPPER LEVEL FEATURES CONTROL THE CARIBBEAN SEA THIS EVENING. AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER WRN CUBA NEAR 22N82W AND EXTENDS UPPER LEVEL RIDGING ACROSS CENTRAL AMERICA TO THE WEST AND EAST TO 71W. UPPER LEVEL DIFFLUENCE ALONG WITH DAYTIME HEATING OVER THE GREATER ANTILLES ARE GENERATING SCATTERED SHOWERS AND TSTMS N OF 17N BETWEEN 72W-82W. ACROSS THE ERN CARIBBEAN E OF 71W...AN UPPER LEVEL LOW IS CENTERED S OF PUERTO RICO NEAR 17N66W AND IS PROVIDING MUCH OF THE CENTRAL CARIBBEAN WITH N-NE FLOW ALOFT AND THE ERN CARIBBEAN WITH MOIST SOUTHERLY FLOW E OF 66W. UPPER LEVEL DIFFLUENCE E OF THE UPPER LOW ALONG WITH ATMOSPHERIC INSTABILITY ARE GENERATING SCATTERED SHOWERS AND TSTMS OVER THE FAR ERN CARIBBEAN E OF 65W AND OVER THE LESSER ANTILLES. ATLANTIC OCEAN... A 1009 MB SURFACE LOW IS OVER THE W ATLC NEAR 29N72W WITH A WARM FRONT EXTENDING NE TO BEYOND 32N70W. A SURFACE TROUGH EXTENDS S FROM THE LOW ACROSS THE CENTRAL BAHAMAS TO ERN CUBA NEAR 22N77W. UPPER LEVEL RIDGING IS ALOFT OVER THE LOW AND IS AIDING IN SUSTAINING CONVECTION ALONG THE SURFACE BOUNDARY. SCATTERED SHOWERS AND TSTMS ARE STRETCHED OVER A LARGE PORTION OF THE W ATLC FROM 22N-32N BETWEEN 64W-75W. FARTHER TO THE SE...THE UPPER LEVEL LOW CENTERED S OF PUERTO RICO NEAR 17N66W IS PROVIDING UPPER LEVEL DIFFLUENCE OVER THE ERN CARIBBEAN AND PORTIONS OF THE TROPICAL N ATLC. SCATTERED SHOWERS AND TSTMS ASSOCIATED WITH THIS UPPER LOW ARE FROM 10N-22N BETWEEN 57W-64W. A 1013 MB SURFACE LOW...THE REMNANT OF FRED...IS CENTERED OVER THE CENTRAL ATLC NEAR 20N47W. NEW SCATTERED STRONG CONVECTION HAS BLOSSOMED N OF THE LOW CENTER OVER THE PAST 6 HOURS AND IS LOCATED FROM 20N-23N BETWEEN 46W-49W. ANOTHER 1013 MB LOW IS W OF THE CAPE VERDE ISLANDS CENTERED NEAR 17N30W. DISORGANIZED SCATTERED SHOWERS AND TSTMS ARE IN THE VICINITY OF THE LOW FROM 13N-19N BETWEEN 28W-33W. THIS ACTIVITY IS BEING ENHANCED AND SUPPORTED ALOFT BY AN UPPER LEVEL RIDGE THAT EXTENDS FROM W AFRICA OVER THE TROPICAL ERN ATLC TO 40W. $$ HUFFMAN