000 AXNT20 KNHC 270604 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN AUG 27 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0345 UTC. ...SPECIAL FEATURES... TROPICAL STORM ERNESTO IS CENTERED NEAR 16.7N 72.7W AT 27/0600 UTC MOVING WNW AT 12 KT OR ABOUT 115 NM SOUTH OF PORT-AU-PRINCE HAITI AND 250 NM EAST-SOUTHEAST OF KINGSTON JAMAICA. ESTIMATED MINIMUM CENTRAL PRESSURE IS 995 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. SEE THE LATEST NHC FORECAST/ADVISORY UNDER HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. LOW LEVEL CENTER REMAINS EMBEDDED WITHIN THE STRONGEST CONVECTION. SCATTERED STRONG CONVECTION IS WITHIN A 45 NM RADIUS OF 16.5N72.5W WITH SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERING THE REMAINDER OF THE AREA FROM 15N-18N BETWEEN 66W-74W. OUTER RAINBANDS ARE TO THE N OF THE SYSTEM AND COVERS THE AREA FROM 18N-20N BETWEEN 67W-75W INCLUDING PORTIONS OF PUERTO RICO AND HISPANIOLA WITH RAINFALL AMOUNTS OF 6 TO 12 INCHES EXPECTED OVER HISPANIOLA AND HIGHER AMOUNTS ARE POSSIBLE IN MOUNTAINOUS REGIONS. TROPICAL DEPRESSION DEBBY IS CENTERED NEAR 27.9N 48.5W AT 27/0300 UTC MOVING NNW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1012 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT. SEE THE LATEST NHC FORECAST/ADVISORY UNDER HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. THE LOW LEVEL CENTER REMAINS COMPLETELY EXPOSED WITH SCATTERED SHOWERS WELL N OF THE CENTER FROM 28N-32N BETWEEN 46W-50W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 28W S OF 22N WITH A 1012 MB LOW ALONG THE WAVE NEAR 18N MOVING W 15-20 KT. WAVE/LOW REMAINS EMBEDDED WITHIN AN AREA OF DRY AIR AND AFRICAN DUST LIMITING ACTIVITY ALONG THE N PORTION OF THE WAVE TO SCATTERED SHOWERS W OF THE AXIS WITHIN 45/60 NM RADIUS OF 17N30.5W. SCATTERED MODERATE CONVECTION IS S OF THE ITCZ AXIS WITHIN 75 NM OF 7.5N FROM 27W-32W. TROPICAL WAVE IS ALONG 90W/91W S OF 20N MOVING W 15-20 KT. WAVE IS INLAND OVER THE YUCATAN PENINSULA INTO THE E PACIFIC REGION WITH THE N PORTION EMBEDDED WITHIN DRY AIR...LIMITING ANY CONVECTION. ...THE ITCZ... ITCZ IS CENTERED ALONG 16N15W 17N25W THEN ALONG 12N31W 10N50W 9N62W ACROSS THE S CARIBBEAN ALONG 12N75W OVER COSTA RICA NEAR 10N84W INTO THE E PACIFIC REGION. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 5N-11N BETWEEN 46W-57W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE REMAINS ANCHORED OVER THE CENTRAL MISSISSIPPI VALLEY WITH AN UPPER TROUGH INLAND OVER CENTRAL MEXICO GENERATING SCATTERED SHOWERS/THUNDERSTORMS INLAND OVER MEXICO. WEAK 1013 MB SURFACE LOW IS ALONG THE NE COAST OF FLORIDA WITH A SURFACE TROUGH EXTENDING ACROSS FLORIDA INTO THE E GULF GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 25N E OF 84W. REMAINDER OF THE GULF REMAINS RATHER CLEAR TONIGHT WITH ONLY BROKEN/OVERCAST HIGH CLOUDS. CARIBBEAN SEA... FOCUS OF WEATHER AGAIN TONIGHT IN THE CARIBBEAN IS TROPICAL STORM ERNESTO. A LARGE UPPER LOW IS DRIFTING W INTO THE W CARIBBEAN CENTERED NEAR 18N84W COVERING THE AREA N OF 13N W OF 77W WITH SCATTERED SHOWERS/THUNDERSTORMS DEVELOPING ALONG THE S COAST OF CUBA. THIS UPPER LOW IS ALSO PREVENTING OUTFLOW TO THE W OF ERNESTO AND APPEARS TO BE WEAKENING ALLOWING ERNESTO TO POSSIBLY FURTHER DEVELOP. BROAD UPPER HIGH IS LOCATED JUST TO THE E OF ERNESTO PRODUCING GOOD OUTFLOW TO THE E OF THE SYSTEM. THESE TWO UPPER FEATURES ARE PRODUCING SOUTHERLY UPPER FLOW OVER THE S CARIBBEAN DRAWING TROPICAL MOISTURE OVER THE CENTRAL CARIBBEAN AND GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 15N W OF 70W TO OVER SOUTH AMERICA... PANAMA...AND COSTA RICA. ATLANTIC OCEAN... THE UPPER RIDGE THAT COVERS THE GULF OF MEXICO EXTENDS INTO THE W ATLC W OF 75W GENERATING ISOLATED SHOWERS ALONG W OF 78W. A SMALL...ELONGATED UPPER LOW IS NOTED NEAR 25N70W WITH THE TROUGH EXTENDING INTO THE LARGE UPPER LOW IN THE W CARIBBEAN. A LARGE UPPER LOW IS IN THE CENTRAL ATLC NEAR 27N54W WITH A TROUGH EXTENDING S TO NEAR 16N55W. THIS IS DRAWING SCATTERED SHOWERS/ THUNDERSTORMS S FROM A DEEP LAYERED LOW/TROUGH THAT IS N OF THE REGION COVERING THE AREA N OF 27N FROM 56W-62W. A STRONG UPPER HIGH IS CENTERED NEAR 30N39W COVERING THE AREA N OF 18N FROM 30W-47W. THE INTERACTION OF THE E PORTION OF THE UPPER LOW AND THE W PORTION OF THE UPPER HIGH IS GENERATING THE STRONG SOUTHERLY SHEAR OVER DEBBY. A SECOND UPPER RIDGE COVERS THE REMAINDER OF THE E ATLC EXTENDING OFF THE COAST OF AFRICA ALONG 20N E OF 30W. A 1029 MB HIGH IS JUST NE OF THE AZORES WITH RIDGE AXIS EXTENDING SW NARROWING JUST N OF DEBBY INTO THE W ATLC. MORE AFRICA DUST IS BEING DRAWN INTO THE FAR E ATLC BUT MAINLY FROM 20N-28N E OF 35W THUS LIMITING CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 28W. $$ WALLACE