000 AXNT20 KNHC 271223 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1145 UTC. ...SPECIAL FEATURES... TROPICAL STORM ERNESTO WAS UPGRADED TO HURRICANE AT 27/0900 UTC. HURRICANE ERNESTO IS CENTERED NEAR 17.3N 73.4W AT 27/1200 UTC MOVING NW AT 8 KT OR ABOUT 115 NM SOUTHWEST OF PORT-AU-PRINCE HAITI AND 210 NM SOUTH-SOUTHEAST OF GUANTANAMO CUBA. ESTIMATED MINIMUM CENTRAL PRESSURE IS 997 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 65 KT WITH GUSTS TO 80 KT. SEE THE LATEST NHC FORECAST/ADVISORY UNDER HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. ALTHOUGH THE OUTFLOW IS GOOD IN ALL QUADRANTS...CONVECTION IS MOSTLY IN THE N SEMICIRCLE AND SE OF THE CENTER. SCATTERED STRONG CONVECTION IS WITHIN 45 NM OF LINE 16.5N70W-18N74W. SCATTERED MODERATE/STRONG CONVECTION COVERS THE REMAINDER OF THE AREA FROM 15N-19N BETWEEN 68W-75W AND FROM 13N-15N BETWEEN 70W-73W. OUTER RAINBANDS COVER THE REMAINDER OF HISPANIOLA WITH CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 75 NM OF LINE 13N81W TO OVER JAMAICA NEAR 18N77W. RAINFALL AMOUNTS OF 3 TO 5 INCHES ARE EXPECTED TODAY OVER JAMAICA AND E CUBA WITH 6 TO 12 INCHES EXPECTED OVER HISPANIOLA...HIGHER AMOUNTS ARE POSSIBLE IN MOUNTAINOUS REGIONS WHICH COULD PRODUCE FLASH FLOODS AND MUDSLIDES. TROPICAL DEPRESSION DEBBY IS CENTERED NEAR 28.6N 49.3W AT 27/0900 UTC MOVING NW AT 11 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/ISOLATED THUNDERSTORMS WELL N OF THE CENTER FROM 29N-33N BETWEEN 46W-50W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 30W S OF 22N WITH A 1012 MB LOW ALONG THE WAVE NEAR 17N 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/ISOLATED THUNDERSTORMS W OF THE AXIS WITHIN 45 NM OF LINE 16N30W-18N34W. TROPICAL WAVE IS ALONG 92W S OF 20N MOVING W 15-20 KT. WAVE IS MOSTLY 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 14N16W 9N24W 6N45W 8N53W 8N62W ACROSS THE N PORTION OF SOUTH AMERICA...PANAMA...AND COSTA RICA NEAR 10N84W INTO THE E PACIFIC REGION. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 6N-10N BETWEEN 20W-34W AND FROM 8N-10N BETWEEN 51W-58W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE REMAINS ANCHORED OVER THE US WITH THE UPPER HIGH SHIFTING E TO OVER NE ALABAMA AND THE RIDGE EXTENDING S OVER THE GULF AND E OVER THE W ATLC. WEAK UPPER TROUGH IS OFF THE COAST OF MEXICO FROM 23N96W TO THE W BAY OF CAMPECHE NEAR 18N96W. WEAK 1013 MB SURFACE LOW IS ON THE NE COAST OF FLORIDA WITH A SURFACE TROUGH EXTENDING SW ACROSS FLORIDA INTO THE E GULF GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 27N E OF 86W. REMAINDER OF THE GULF REMAINS RATHER CLEAR THIS MORNING WITH ONLY BROKEN HIGH CLOUDS. CARIBBEAN SEA... FOCUS OF WEATHER AGAIN THIS MORNING IN THE CARIBBEAN IS HURRICANE ERNESTO. A LARGE UPPER LOW IS DRIFTING W OVER THE W CARIBBEAN CENTERED NEAR 17N85W COVERING THE AREA N OF 13N W OF 78W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS E OF THE LOW WITHIN 90 NM OF LINE FROM HONDURAS 16N85W TO CUBA NEAR 22N82W. BROAD UPPER HIGH IS LOCATED JUST TO THE E OF ERNESTO WITH AN UPPER RIDGE EXTENDING ACROSS PUERTO RICO INTO THE W/CENTRAL ATLC. THIS IS PRODUCING GOOD OUTFLOW IN ASSOCIATION WITH ERNESTO. 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 16N FROM 70W-83W 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 70W. AN UPPER TROUGH EXTENDS FROM 27N70W TO THE COAST OF CUBA NEAR 21N76W. UPPER RIDGE FROM NEAR ERNESTO EXTENDS ACROSS PUERTO RICO E OF THE UPPER TROUGH TO NEAR 27N64W. THIS IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 20N-26N BETWEEN 65W-71W. A LARGE UPPER LOW IS IN THE W/CENTRAL ATLC NEAR 25N53W 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...WITHIN 60 NM OF LINE 29N61W TO BEYOND 32N57W. 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. WEAK UPPER RIDGE COVERS THE REMAINDER OF THE E ATLC EXTENDING OFF THE COAST OF AFRICA ALONG 20N E OF 30W. A 1028 MB HIGH IS JUST NE OF THE AZORES WITH RIDGE AXIS EXTENDING SW TO JUST NE OF DEBBY WITH A WEAK 1019 MB HIGH IN THE W/CENTRAL ATLC NEAR 24N59W. THE AFRICAN DUST IS COMING OFF THE COAST OF AFRICA IS BEGINNING TO DIMINISH BUT REMAINS OVER THE E ATLC FROM 20N-30N BETWEEN 20W-37W. $$ WALLACE