000 AXNT20 KNHC 241753 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT JUL 24 2010 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. ...SPECIAL FEATURE... TROPICAL DEPRESSION BONNIE IS CENTERED NEAR 28.0N 86.7W ABOUT 143 NM ESE OF THE MOUTH OF THE MISSISSIPPI RIVER OR ABOUT 135 NM SW OF APALACHICOLA FLORIDA MOVING WNW AT 15 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1014 MB. MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT. SEE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT3/WTNT33 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. THE LOW LEVEL CENTER IS COMPLETELY EXPOSED BY STRONG SOUTHEASTERLY SHEAR. BONNIE IS EXPECTED TO MAKE LANDFALL DURING THE NIGHT TONIGHT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS TO THE NW OF THE LOW CENTER FROM 28N-30N BETWEEN 86W-89W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 15N33W TO 7N39W MOVING W AT 5-10 KT. WAVE REMAINS EMBEDDED WITHIN A MOISTURE MAXIMUM AS EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. WAVE HAS A WELL DEFINED BUT NARROW CYCLONIC CURVATURE ALONG THE WAVE AXIS. ISOLATED SHOWERS ARE WITHIN 60 NM OF THE WAVE AXIS. TROPICAL WAVE IN THE E CARIBBEAN FROM 20N62W TO 10N64W MOVING W AT 20-25 KT. WAVE IS EMBEDDED WITHIN A MOISTURE MAXIMUM AS EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. WAVE CYCLONIC CURVATURE IS ALONG THE WAVE AXIS BUT DUE TO THE DRY SAHARAN AIR LAYER TRAILING THE WAVE AXIS...THE WAVE SIGNATURE IS BECOMING INDISTINCT. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 150 NM NW OF THE WAVE N OF 13N ACROSS THE VIRGIN ISLANDS AND PUERTO RICO. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 11N13W 8N20W 11N32W THEN ALONG 10N40W 8N51W 9N62W. SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF ISOLATED STRONG CONVECTION COVER THE AREA WITHIN 120 NM OF THE ITCZ FROM 15W-24W. CLUSTERS OF ISOLATED MODERATE CONVECTION ARE WITHIN 75 NM OF 10N FROM 40W-52W. ...DISCUSSION... GULF OF MEXICO... TROPICAL DEPRESSION BONNIE REMAINS OVER THE NE GULF OF MEXICO... SEE SPECIAL FEATURES ABOVE. AN UPPER LEVEL LOW REMAINS TO THE W OF BONNIE CENTERED OVER THE NW GULF NEAR 28N94W. A BROAD UPPER HIGH IS OVER THE CENTRAL SOUTH/NORTH CAROLINA BORDER COVERING PORTIONS OF THE W ATLC AND THE E GULF TO CUBA AND E OF 90W. DIFFLUENCE ALOFT AND COUPLED WITH BONNIE ARE PRODUCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 28N TO JUST INLAND OVER THE N GULF COAST FROM APALACHICOLA BAY FLORIDA VERMILION BAY LOUISIANA. A SURFACE TROUGH IN THE SW GULF EXTENDS FROM NEAR TAMPICO MEXICO ALONG THE COAST INTO S MEXICO NEAR COATZACOALCOS TO N GUATEMALA NEAR 16N90W PRODUCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE BAY OF CAMPECHE S OF 23N W OF 94W TO INLAND OVER MEXICO. CARIBBEAN SEA... AN UPPER LOW IS JUST N OF THE WINDWARD PASSAGE/E CUBA COVERING THE N CARIBBEAN N OF 18N BETWEEN 73W-80W SUPPORTING A WEAK SURFACE TROUGH THAT EXTENDS FROM 18N73W ACROSS E CUBA TO SE BAHAMAS BEYOND 22N94W. OVERCAST MULTILAYERED CLOUDS WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE TO THE SW OF THE SURFACE TROUGH WITHIN 120 NM OF A LINE FROM 16N75W ACROSS HISPANIOLA NEAR 19N72W. AN UPPER RIDGE OVER THE W ATLC AND E GULF OF MEXICO DIPS S OVER E CUBA. THESE FEATURES ARE GIVING THE W CARIBBEAN NE TO E FLOW ALOFT AND COUPLED WITH DIFFLUENCE ALOFT ARE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 17N TO THE COAST OF PANAMA AND COLOMBIA BETWEEN 74W-82W AND WITHIN 60 NM OF LINE FROM 17N82W TO THE COAST OF CUBA NEAR THE ISLE OF YOUTH. A TROPICAL WAVE IS OVER THE E CARIBBEAN PRODUCING SHOWERS/THUNDERSTORM ACTIVITY E OF 68W. ATLANTIC OCEAN... AN UPPER HIGH IS OVER THE CENTRAL SOUTH/NORTH CAROLINA BORDER COVERING THE E GULF OF MEXICO AND PORTIONS OF THE W ATLC W OF 72W BEING NARROWED W OF 80W BY AN UPPER LOW BETWEEN THE BAHAMAS AND CUBA NEAR 21N72W. A SECOND UPPER LOW IS TO THE E NEAR 22N65W ENHANCING THE ACTIVITY ASSOCIATED WITH THE TROPICAL WAVE OVER THE E CARIBBEAN. THE WESTERN UPPER LOW COVERS THE AREA S OF 25N E OF 79W SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 24N72W ACROSS THE BAHAMAS AND CUBA NEAR 20N75W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 23N TO OVER CUBA AND HISPANIOLA BETWEEN 70W-77W. AN UPPER TROUGH IS OVER THE CENTRAL ATLC EXTENDING THROUGH 32N27W SW TO 17N48W. DRY STABLE AIR AND STRONG SUBSIDENCE COVERS MUCH OF THE ATLC BASIN FROM 10N-30N BETWEEN 20W-60W THEN NARROWING AND BEING DRAWN INTO THE UPPER LOW N OF CUBA FROM 22N-28N BETWEEN 60W-70W. A SURFACE RIDGE DOMINATES THE ATLC N OF 20N E OF 60W THEN NARROWS TO N OF 30N BETWEEN 60W AND THE E COAST OF GEORGIA AND SOUTH CAROLINA WITH A 1023 MB HIGH NEAR 29N59W. A WEAKNESS IS EMBEDDED WITHIN THE SURFACE RIDGE IN THE IMMEDIATE VICINITY OF A SURFACE TROUGH THAT EXTENDS FROM 32N49W TO 26N55W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW