000 AXNT20 KNHC 252358 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI AUG 25 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... HURRICANE HUNTER AIRCRAFT HAS DETERMINED THAT TROPICAL DEPRESSION FIVE HAS BECOME TROPICAL STORM ERNESTO. THE CENTER OF ERNESTO AT 25/2100 UTC IS NEAR 14.3N 67.6W MOVING WEST-NORTHWEST AT 14 KT. THIS POSITION IS ALSO ABOUT 260 NM SOUTH-SOUTHWEST OF SAN JUAN PUERTO RICO AND ABOUT 570 NM EAST-SOUTHEAST OF KINGSTON JAMAICA. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 35 KT WITH GUSTS TO 45 KT. FOR MORE DETAILS SEE THE LATEST NHC FORECAST/ADVISORY UNDER HEADERS MIATCMAT5/WTNT25 KNHC...AND THE LATEST PUBLIC ADVISORY UNDER MIATCPAT5/WTNT35 KNHC. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS DISPLACED MAINLY WEST OF THE CENTER FROM 12N-16N BETWEEN 61W-68W. RAINFALL AMOUNTS OF 3 TO 6 INCHES ARE EXPECTED IN ASSOCIATION WITH ERNESTO ACROSS PORTIONS OF HISPANIOLA AND JAMAICA...WITH 1-3 INCHES EXPECTED FOR PARTS OF PUERTO RICO AND THE DUTCH NETHERLAND ANTILLES. THE CENTER OF TROPICAL STORM DEBBY AT 25/2100 UTC IS NEAR 24.9N 44.7W MOVING NORTHWEST AT 15 KT. THIS POSITION IS ALSO ABOUT 1280 NM WEST-NORTHWEST OF THE CAPE VERDE ISLANDS...OVER THE OPEN WATERS OF THE CENTRAL ATLANTIC. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 35 KT WITH GUSTS TO 45 KT. FOR MORE DETAILS READ THE LATEST NHC FORECAST/ADVISORY UNDER HEADERS MIATCMAT4/WTNT24 KNHC...AND THE LATEST PUBLIC ADVISORY UNDER MIATCPAT4/WTNT34 KNHC. STRONG SOUTHERLY SHEAR CONTINUES TO DISPLACE THE CIRCULATION TO THE SOUTH OF THE DEEP CONVECTION. ...TROPICAL WAVES... A 1007 MB LOW IS JUST WEST OF THE COAST OF SENEGAL NEAR 16N18W MOVING W NEAR 10 KT. POSITION IS BASED ON SURFACE OBSERVATIONS AND SATELLITE IMAGERY. SHOWERS AND TSTMS ASSOCIATED WITH THIS LOW HAVE DIMINISHED OVER THE PAST FEW HOURS...THOUGH THIS MAY BE PARTLY DIURNAL. A TROPICAL WAVE IS OVER THE W CARIBBEAN ALONG 82W SOUTH OF 20N MOVING WEST 15-20 KT. DETECTION OF THIS WAVE REMAINS DIFFICULT THOUGH THERE ARE SOME VAGUE SIGNS OF WESTWARD PROPAGATING CONVECTION NOTED ON THE HOVMOLLER DIAGRAMS ON THE TAFB WEBSITE. SCATTERED MODERATE CONVECTION IS OVER THE SW CARIBBEAN...COSTA RICA...AND PANAMA...AND THE FAR NE PACIFIC FROM 4N-12N BETWEEN 78W-84W. ...THE ITCZ... ITCZ IS CENTERED ALONG 11N15W 7N23W 7N50W 9N62W. A PORTION OF THE ITCZ IS ALSO OVER THE SRN CARIBBEAN ALONG 10N75W TO 9N81W. SCATTERED MODERATE CONVECTION IS FROM 5N-11N BETWEEN THE COAST OF AFRICA AND 24W. VERY LITTLE SHOWER/TSTM ACTIVITY IS NOTED W OF 25W TO 60W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE ALSO FOUND IN THE SW CARIBBEAN FROM 8N-12N BETWEEN 73W-80W. ...DISCUSSION... THE GULF OF MEXICO... THE REMAINDER OF THE UPPER LOW THAT HAS MOVED W ACROSS THE GULF THE LAST FEW DAYS IS LOCATED NEAR 23N93W IN THE WSW GULF...BUT ONLY VAGUE MID TO UPPER CYCLONIC MOTION IS NOTED IN THIS EVENINGS WATER VAPOR IMAGERY. ISOLATED SHOWERS/TSTMS DOT THE AREA WITHIN 200NM OF THIS UPPER LOW. MID TO UPPER ANTICYCLONIC FLOW DOMINATES THE NORTH AND EASTERN GULF...WITH AN UPPER HIGH OVER E TEXAS AND ANOTHER IN THE NE GULF NEAR 28N86W. UPPER DIFFLUENCE BETWEEN THE UPPER HIGH OVER E TEXAS AND THE WEAKENING UPPER LOW IN THE WSW GULF IS GENERATING SCATTERED MODERATE CONVECTION OFF THE TEXAS AND LOUISIANA COASTS...FROM 25N-30N BETWEEN 90W-98W. ISOLATED SHOWERS/TSTMS ARE ALSO NOTED IN THE ERN GULF FROM 24N-31N BETWEEN THE W COAST OF FLORIDA AND 87W...WHICH IS THE AREA SOUTH OF A DYING STATIONARY FRONT OVER THE SE STATES ACCOMPANIED BY UPPER HIGH PRESSURE. THE OTHER SIGNIFICANT WEATHER IN THE GULF IS A CLUSTER OF SCATTERED MODERATE CONVECTION BEGINNING TO MOVE INTO THE ERN BAY OF CAMPECHE...WHICH HAS BEEN CONSISTENT THAT LAST FEW EVENINGS. THE WRN PORTION OF THE ATLC HIGH CONTINUES TO DOMINATE THE SURFACE PATTERN...WITH SFC WINDS GENERALLY LIGHT AND SEAS LOW. SLIGHTLY STRONGER 15KT SE WINDS FOUND IN THE W/SW GULF AS THE HIGH INTERACTS WITH LOWER PRESSURE OVER MEXICO. THE CARIBBEAN SEA... TROPICAL STORM ERNESTO...A TROPICAL WAVE...AND A PORTION OF THE ITCZ...ARE OVER THE CARIBBEAN BASIN. THESE FEATURES ARE GENERATING THE MAJORITY OF THE WEATHER OVER THE CARIBBEAN THIS EVENING. A MID TO UPPER LEVEL LOW IS SEEN SPINNING JUST SOUTH OF ERN CUBA. ISOLATED SHOWERS AND TSTMS ARE ROTATING COUNTER-CLOCKWISE AROUND THIS FEATURE. HIGH CLOUDS IN THE CENTRAL CARIBBEAN...BETWEEN NICARAGUA AND HISPANIOLA...ARE STREAMING QUICKLY TO THE NE WITH THE STRONG UPPER LEVEL SW FLOW BETWEEN THE UPPER LOW S OF ERN CUBA AND AN UPPER HIGH NEAR 14N71W. ASIDE FROM ERNESTO AND THE TROPICAL WAVE...THE S/SW PORTION OF ATLC HIGH PRESSURE CONTINUES TO DOMINATE THE LOWER LEVELS OF THE ATMOSPHERE OVER THE CARIBBEAN. THE ATLANTIC OCEAN... CLUSTERS OF SCATTERED MODERATE CONVECTION AND SHOWERS/TSTMS ARE SEEN NEAR A STATIONARY SURFACE FRONT EXTENDING ENE FROM THE GEORGIA/N FLORIDA COAST...FROM 27N TO 33N BETWEEN 60W-80W. THIS REGION IS ALSO DOMINATING BY AN UPPER RIDGE AXIS EXTENDING ENE FROM CENTRAL FLORIDA. A SMALL UPPER LOW IS NOTED NEAR 23N66W...ABOUT 350NM N OF PUERTO RICO. SHOWER ACTIVITY ASSOCIATED WITH THIS FEATURE IS MINIMAL. A LARGER UPPER LOW IS SEEN SPINNING NEAR 30N52W. THIS IS GENERATING ISOLATED SHOWER/TSTMS FROM 21N-30N BETWEEN 50W-58W. THE INTERACTION OF THE E PORTION OF THIS UPPER LOW AND THE W PORTION OF LARGE SCALE MID TO UPPER RIDGING OFF THE COAST OF AFRICA IS GENERATING THE STRONG SOUTHERLY SHEAR OVER DEBBY. THERE ARE A FEW EMBEDDED UPPER HIGH CENTERS FROM THE COAST OF AFRICA W TO 40W. AT THE SURFACE A 1028MB AZORES HIGH DOMINATES MUCH OF OUR ATLANTIC WATERS OUTSIDE OF DEBBY AND THE WEAK LOW OFF OF SENEGAL. $$ WILLIS