000 AXNT20 KNHC 122355 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE AUG 12 2008 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... TROPICAL WAVE IS IN THE W TROPICAL ATLANTIC ALONG 52W S OF 21N OR ABOUT 500 NM E OF THE LESSER ANTILLES WITH A 1008 MB LOW ALONG THE WAVE NEAR 16N MOVING W 10-15 KT. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE N OF THE LOW FROM 16N-20N BETWEEN 48W-54W. A TROPICAL DEPRESSION COULD FORM DURING THE NEXT DAY OR SO WITH THE SHOWER ACTIVITY MOVING OVER BARBADOS LATE TONIGHT. A 1009 MB LOW IS IN THE E TROPICAL ATLC NEAR 12N34W. ISOLATED SHOWERS ARE WITHIN 120 NM OF THE LOW. THIS SYSTEM HAS CHANGED LITTLE IN ORGANIZATION SINCE YESTERDAY...A TROPICAL DEPRESSION COULD STILL FORM WITHIN THIS BROAD AREA OF WEATHER DURING THE NEXT DAY OR TWO AS IT MOVES W 10-15 MPH. ...TROPICAL WAVES... TROPICAL WAVE IS W OF THE CAPE VERDE ISLANDS ALONG 28W S OF 18N MOVING W NEAR 15 KT. AN ELONGATED AREA OF LOWER PRESSURE AS WELL AS THE MIMIC-TPW SHOWS A BROAD AREA OF DEEP LAYERED MOISTURE SURROUNDING THIS WAVE AND THE 1009 MB LOW IN THE SPECIAL FEATURES ...SEE ABOVE. SCATTERED MODERATE CONVECTION IS MOSTLY W OF THE WAVE AXIS FROM 14N-16N BETWEEN 32W-33W. TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN ALONG 77W S OF 19N MOVING W NEAR 15 KT. WAVE POSITION IS BASED ON CONTINUITY AS HIGH CLOUDS COVER THE AREA OF THE CARIBBEAN IS MASKING LOW CLOUD SIGNATURE. THE MIMIC-TPW SHOWS A LOW AMPLITUDE AREA OF DEEP LAYERED MOISTURE COVERING THE SW CARIBBEAN MAINLY S OF 15N. SCATTERED MODERATE CONVECTION IS W OF THE WAVE AXIS FROM 12N-16N BETWEEN 77W-81W. TROPICAL WAVE IS IN THE W CARIBBEAN ALONG 88W S OF 21N MOVING W 15-20 KT. CLUSTERS OF WIDELY SCATTERED MODERATE CONVECTION IS INLAND OVER CENTRAL AMERICA FROM COSTA RICA TO GUATEMALA. ...THE ITCZ... THE ITCZ IS CENTERED ALONG 11N16W 14N29W 9N40W 15N52W 10N61W. CLUSTERS OF WIDELY SCATTERED MODERATE CONVECTION ARE ALONG THE COAST OF W AFRICA FROM 6N-11N BETWEEN 10W-20W. ISOLATED MODERATE CONVECTION IS FROM 9N-11N BETWEEN 41W-51W. ...DISCUSSION... GULF OF MEXICO... A FRONTAL SYSTEM IS INLAND OVER THE N GULF STATES PRODUCING WIDELY SCATTERED MODERATE CONVECTION N OF 28N. AIRMASS SHOWERS AND THUNDERSTORMS ARE ALSO INLAND OVER S FLORIDA FROM 25N-28N BETWEEN 80W-82W. A 1015 MB HIGH IS CENTERED OVER THE STRAITS OF FLORIDA NEAR 24N79W. 5-10 KT ANTICYCLONIC WINDS ARE OVER THE SE GULF OF MEXICO. 15 KT SLY SURFACE WINDS ARE OVER THE W GULF OF MEXICO W OF 90W. MOSTLY FAIR WEATHER IS OVER THE S GULF S OF 25N. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED OVER CENTRAL TEXAS NEAR 31N100W PRODUCING NE TO E UPPER LEVEL FLOW OVER THE GULF OF MEXICO. CONSIDERABLE UPPER LEVEL MOISTURE IS OVER THE N GULF N OF 25N. EXPECT WEAK FRONTAL ACTIVITY TO PRODUCE CONVECTION OVER THE NE GULF STATES N OF 28N DURING THE NEXT 24 HOURS. CARIBBEAN SEA... TWO TROPICAL WAVES ARE TRAVERSING THE CARIBBEAN SEA. SEE ABOVE. MODERATE TO STRONG EASTERLY TRADEWINDS ARE BLOWING ACROSS THE BASIN WITH THE STRONGEST WINDS OFF THE NRN COLOMBIAN COAST. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION ...ISOLATED MODERATE CONVECTION IS OVER E CUBA BETWEEN 75W-79W. ISOLATED MODERATE CONVECTION IS ALSO INLAND OVER PANAMA BETWEEN 77W-83W. IN THE UPPER LEVELS...A SMALL UPPER LEVEL LOW IS CENTERED OVER THE CAYMAN ISLANDS NEAR 19N82W. AN UPPER LEVEL HIGH IS CENTERED OVER N COLOMBIA NEAR 11N73W. AN UPPER LEVEL LOW IS CENTERED N OF PUERTO RICO NEAR 21N67W. CONSIDERABLE UPPER LEVEL MOISTURE IS BETWEEN 70W-90W. STRONG SUBSIDENCE IS OVER THE E CARIBBEAN E OF 70W. EXPECT...CONVECTION OVER THE SW CARIBBEAN AND CENTRAL AMERICA DURING THE NEXT 24 HOURS. ALSO EXPECT SCATTERED SHOWERS OVER THE LEEWARD ISLANDS AS THE NEXT TROPICAL WAVE APPROACHES THE LESSER ANTILLES. ATLANTIC OCEAN... A DOMINATE 1024 MB HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 36N40W. A SURFACE RIDGE AXIS EXTENDS SW TO THE STRAITS OF FLORIDA NEAR 24N80W. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE W ATLANTIC N OF 28N AND W OF 70W. ISOLATED MODERATE CONVECTION IS FROM 27N-30N BETWEEN 65W-71W. AN UPPER LEVEL HIGH IS OVER THE W ATLANTIC NEAR 28N62W. FURTHER E...AN UPPER LEVEL LOW IS CENTERED NEAR 29N51W. AN UPPER LEVEL HIGH IS OVER THE TROPICAL ATLANTIC NEAR 18N44W. AN UPPER LEVEL LOW IS E OF THE CANARY ISLANDS NEAR 30N31W. AN UPPER LEVEL HIGH IS CENTERED OVER THE CAPE VERDE ISLANDS NEAR 18N27W. EXPECT THE TROPICAL WAVES TO BE THE PRIMARY WEATHER PRODUCERS OVER THE NEXT 24 HOURS. ALSO EXPECT PREFRONTAL ACTIVITY OVER THE W ATLANTIC N OF 27N AND W OF 60W. $$ FORMOSA