000 AXNT20 KNHC 200002 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT SEP 19 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. ...SPECIAL FEATURES... A 1008 MB LOW IS CENTERED E OF THE WINDWARD ISLANDS NEAR 13N43W. THE LOW HAS THE POTENTIAL TO BECOME A TROPICAL DEPRESSION OVER THE NEXT DAY OR TWO AS IT MOVES TO THE WNW NEAR 8 KT. ISOLATED MODERATE CONVECTION IS N IF THE CENTER FROM 13N-17N BETWEEN 40W-44W. SCATTERED SHOWERS COVERS A LARGE AREA FROM 9N-20N BETWEEN 36W-45W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 29W S OF 17N MOVING W NEAR 10 KT. A SMALL SWIRL IS EMBEDDED ON THE WAVE AXIS NEAR 16N. SCATTERED MODERATE CONVECTION IS W OF THE AXIS FROM 15N-18N BETWEEN 31W-33W. TROPICAL WAVE IS ALONG 95W S OF 20N MOVING W NEAR 15 KT. WAVE IS MOSTLY OVER SOUTH MEXICO AND IN THE E PACIFIC REGION WITH A SMALL AREA OF INVERTED TROUGH IN THE BAY OF CAMPECHE. A LARGE AREA OF SCATTERED MODERATE TO STRONG CONVECTION IS INLAND OVER THE YUCATAN PENINSULA FROM 16N-21N BETWEEN 88W-91W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N9W 6N20W 15N30W 11N50W 10N63W. BESIDES THE CONVECTION MENTIONED ON THE SPECIAL FEATURES AND TROPICAL WAVE SECTIONS...SCATTERED MODERATE TO STRONG CONVECTION IS ALONG THE COAST OF WEST AFRICA FROM 8N-12N BETWEEN 11W-16W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A SURFACE TROUGH EXTENDS FROM S LOUISIANA NEAR 29N91W TO THE NW GULF OF MEXICO NEAR 25N93W. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE TROUGH AXIS. FURTHER E...SCATTERED MODERATE CONVECTION IS OVER THE FLORIDA PANHANDLE FROM 30N-32N BETWEEN 84W-86W. SIMILAR CONVECTION IS OVER S FLORIDA FROM 25N-27N BETWEEN 80W-82W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED OVER MEXICO NEAR 20N100W. ANOTHER UPPER LEVEL HIGH IS OVER THE STRAITS OF FLORIDA NEAR 24N81W. CONSIDERABLE UPPER LEVEL MOISTURE COVERS THE GULF OF MEXICO. EXPECT... LITTLE CHANGE OVER THE NEXT 24 HOURS. CARIBBEAN SEA... MODERATE TO FRESH TRADEWINDS ARE OVER THE CARIBBEAN SEA AND CENTRAL AMERICA. PATCHES OF WIDELY SCATTERED MODERATE CONVECTION ARE OVER THE W CARIBBEAN W OF 78W...OVER THE N CARIBBEAN N OF 18N... AND OVER SOUTH AMERICA S OF 12N. IN THE UPPER LEVELS... AN UPPER LEVEL TROUGH IS OVER THE SW CARIBBEAN. AN UPPER LEVEL LOW IS N OF THE LEEWARD ISLANDS NEAR 20N66W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 18N-21N BETWEEN 60W-65W. EXPECT... CONTINUED CONVECTION OVER THE WESTERN AND NORTHERN CARIBBEAN OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... SCATTERED MODERATE CONVECTION IS OVER THE N BAHAMAS FROM 26N-28N BETWEEN 77W-80W. FURTHER E...A SURFACE TROUGH IS OVER THE W ATLANTIC FROM 31N70W TO 23N70W. AN EMBEDDED 1014 MB LOW IS ON THE TROUGH AXIS NEAR 28N70W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 25-27N BETWEEN 69W-71W. A 1025 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 33N41W PRODUCING FAIR WEATHER. IN THE UPPER LEVELS... A LARGE UPPER LEVEL LOW IS OVER THE E ATLANTIC NEAR 30N27W. A LARGE UPPER LEVEL HIGH IS OVER THE TROPICS NEAR 1N28W PRODUCING MAINLY UPPER LEVEL EASTERLIES S OF 10N BETWEEN 10W-50W. $$ FORMOSA