000 AXNT20 KNHC 112354 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE SEP 11 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 FEATURE... SHOWER AND THUNDERSTORM ACTIVITY HAS PERSISTED THIS EVENING IN ASSOCIATION WITH A TROPICAL WAVE AND BROAD AREA OF LOW PRESSURE LOCATED ABOUT 1200 MILES EAST OF THE WINDWARD ISLANDS ALONG 41W. SCATTERED MODERATE CONVECTION IS FROM 11N-13N BETWEEN 41W-44W... AND FROM 7N-10N BETWEEN 43W-46W. CONDITIONS APPEAR FAVORABLE FOR DEVELOPMENT...AND THIS SYSTEM COULD BECOME A TROPICAL DEPRESSION WITHIN A DAY OR TWO AS IT MOVES WEST-NORTHWESTWARD NEAR 10 MPH. A BROAD LOW PRESSURE AREA THAT IS CENTERED ABOUT 100 MILES EAST OF THE LOWER TEXAS COAST IS PRODUCING DISORGANIZED SHOWERS AND THUNDERSTORMS. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR SOME DEVELOPMENT OF THIS SYSTEM AS IT DRIFTS SLOWLY WESTWARD OVER THE NEXT DAY OR TWO. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 29W S OF 22N MOVING W 15 KT. THIS REMAINS A LARGE AMPLITUDE WAVE WITH VISIBLE SATELLITE IMAGERY INDICATING BROAD TURNING IN THE STRATOCUMULUS FIELD BETWEEN 24W-36W. WHILE THE WAVE STRUCTURE IS WELL DEFINED...CONVECTION REMAINS CONFINED TO THE ITCZ. WIDELY SCATTERED MODERATE CONVECTION IS FROM 5N-8N BETWEEN 23W-28W. ISOLATED MODERATE CONVECTION IS FROM 8N-12N BETWEEN 31W-35W. A TROPICAL WAVE IS IN THE E CARIBBEAN ALONG 68W S OF 20N MOVING W 10 TO 15 KT. A WEAK INVERTED-V SIGNATURE IS SEEN ON SATELLITE IMAGERY. THE WAVE IS INTERACTING WITH A BROAD UPPER LOW THAT IS OVER HISPANIOLA. CLUSTERS OF ISOLATED MODERATE CONVECTION IS OVER THE LEEWARD ISLANDS FROM 13N-20N BETWEEN 65W-72W. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 11N15W 9N20W 13N35W 9N50W 10N60W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES... AN AREA OF SCATTERED MODERATE TO STRONG CONVECTION IS JUST INLAND OVER W AFRICA FROM 10N-16N BETWEEN 11W-17W PROBABLY ASSOCIATED WITH THE NEXT TROPICAL WAVE. WIDELY SCATTERED MODERATE CONVECTION IS OVER THE WINDWARD ISLANDS FROM 8N-12N BETWEEN 61W-66W. DISCUSSION... THE GULF OF MEXICO... THE MAIN FEATURE IN THE GULF IS A 1012 MB LOW CENTERED OVER THE NW GULF NEAR 27N95W. A TROUGH EXTENDS SOUTH FROM THE LOW TO THE BAY OF CAMPECHE NEAR 19N94W. SCATTERED MODERATE CONVECTION IS NEAR THE LOW CENTER FROM 24N-28N BETWEEN 91W-99W. FURTHER N... A WEAK COLD FRONT WITH SCATTERED SHOWERS IS APPROACHING THE COAST OF TEXAS. FURTHER S...SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS INLAND OVER THE YUCATAN PENINSULA FROM 16N-21N BETWEEN 87W-91W. SIMILAR CONVECTION IS OVER W CUBA FROM 21N-23N BETWEEN 80W-85W. ISOLATED MODERATE CONVECTION IS OVER INLAND FLORIDA. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE E GULF PRODUCING NLY FLOW. A SMALL UPPER LEVEL HIGH IS OVER THE BAY OF CAMPECHE NEAR 19N93W. AN UPPER LEVEL LOW IS OVER INLAND MEXICO NEAR 21N103W. SIGNIFICANT UPPER LEVEL MOISTURE WITH BROKEN HIGH CLOUDS COVERS THE ENTIRE GULF OF MEXICO. EXPECT THE FRONT TO STALL JUST N OF THE GULF LOW DURING THE NEXT 24 HOURS THUS WEATHER CONDITIONS WILL NOT CHANGE MUCH OVER THE GULF OF MEXICO DURING THE PERIOD. THE CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE EASTERN CARIBBEAN SEA. SEE ABOVE. LIGHT TO MODERATE TRADES ARE OVER THE REMAINDER OF THE SEA. A 1005 MB LOW IS CENTERED OVER N COLOMBIA NEAR 8N77W. ISOLATED MODERATE CONVECTION IS OVER N COLOMBIA AND PANAMA FROM 5N-10N BETWEEN 73W-83W. SIMILAR CONVECTION IS OVER CUBA...JAMAICA... AND THE W CARIBBEAN FROM 17N-21N BETWEEN 75W-85W. IN THE UPPER LEVELS...AN UPPER LEVEL LOW OVER HISPANIOLA IS PRODUCING MOSTLY WLY UPPER LEVEL FLOW OVER THE ENTIRE CARIBBEAN SEA THAT HINDERS TROPICAL DEVELOPMENT OVER THE TROPICAL WAVE. EXPECT CONVECTION WITH THE TROPICAL WAVE DURING THE NEXT 24 HOURS. ALSO EXPECT CONVECTION OVER THE WESTERN CARIBBEAN AND CENTRAL AMERICA W OF 75W DURING THE NEXT 24 HOURS. THE ATLANTIC OCEAN... A 1022 MB HIGH IS OVER THE W ATLANTIC NEAR 32N60W. A WEAK SURFACE TROUGH IS OVER THE CENTRAL ATLANTIC ALONG 32N36W 28N40W. ISOLATED MODERATE CONVECTION IS WITHIN 60 NM E OF THE TROUGH. A 1021 MB HIGH IS OVER THE E ATLANTIC NEAR 32N28W. IN THE UPPER LEVELS... A TROUGH IS OVER THE W ATLANTIC W OF 60W. A LARGE UPPER LEVEL HIGH IS OVER THE CENTRAL TROPICAL ATLANTIC NEAR 17N45W. A RIDGE AXIS EXTENDS E AND W BETWEEN 15W-60W. $$ FORMOSA