000 AXNT20 KNHC 292337 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI JUL 29 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM DON IS CENTERED NEAR 27.1N 97.1W AT 30/0000 UTC OR ABOUT 50 MI...85 KM SSE OF CORPUS CHRISTI TEXAS...OR ABOUT 85 MI...135 KM NNE OF BROWNSVILLE TEXAS MOVING W-NW AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SATELLITE IMAGERY SHOWS THAT DON REMAINS A SHEARED SYSTEM A LOW-LEVEL CENTER NEAR THE NORTHEASTERN EDGE OF A DISORGANIZED MASS OF STRONG CONVECTION FROM 24N-28N BETWEEN 95W-100W. THE FORECAST TRACK CALLS FOR THE SYSTEM TO MAKE LANDFALL BETWEEN BROWNSVILLE AND CORPUS CHRISTI WITHIN A FEW HOURS...FOLLOWED BY A MOTION ACROSS SOUTH TEXAS INTO NORTHEASTERN MEXICO. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/ WTNT34 KNHC AND THE FULL FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. TROPICAL WAVE IS ANALYZED FROM 20N45W TO 10N42W MOVING W AT 15-20 KT. A 1007 MB LOW IS CENTERED NEAR THE SOUTHERN EXTENT OF THE WAVE NEAR 10N42W AND CONTINUES TO BE LOCATED BENEATH THE SOUTHERN PERIPHERY OF AN UPPER LEVEL ANTICYCLONIC CIRCULATION OVER THE CENTRAL TROPICAL ATLC CENTERED NEAR 15N41W. AN AREA OF INCREASED TOTAL PRECIPITABLE WATER ALSO COINCIDES WITH THE WAVE AXIS. ISOLATED MODERATE CONVECTION IS FROM 06N-14N BETWEEN 35W-48W. THIS WAVE WARRANTS WATCHING AS SOME MODELS FORECAST DEVELOPMENT WITH A THREAT TO THE LESSER ANTILLES. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED W OF THE CAPE VERDE ISLANDS FROM 22N26W TO 11N27W MOVING W AT 15 KT. TOTAL PRECIPITABLE WATER IMAGERY SHOWS A VERY DISTINCT AREA OF LOW-LEVEL MOISTURE. NO SIGNIFICANT CONVECTION IS NOTED WITH THE WAVE AT THIS TIME. TROPICAL WAVE IS ANALYZED OVER THE CENTRAL CARIBBEAN FROM 20N77W TO 11N77W MOVING W AT 15-20 KT. BOTH LOWER LEVEL STREAMLINE ANALYSIS AND NEAR 700 MB MODEL EVALUATION INDICATES THE WAVE REMAINS BROAD. THIS IS CONFIRMED IN TOTAL PRECIPITABLE WATER IMAGERY AS VALUES OF LOW-LEVEL MOISTURE ARE MAXIMIZED S OF 20N BETWEEN 67W-85W. THE WAVE IS JUST N OF THE MONSOON TROUGH AND THE ASSOCIATED LOW-LEVEL CYCLONIC GYRE CENTERED OVER THE SW CARIBBEAN NEAR 11N81W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 12N-21N BETWEEN 70W-83W TO INCLUDE HAITI...JAMAICA...AND E CUBA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 20N0W TO 17N10W TO THE AFRICAN COAST NEAR 13N17W TO 12N21W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 12N21W TO 14N28W TO 11N40W TO THE COAST OF SURINAME AT 9N56W. ISOLATED MODERATE CONVECTION IS N OF SURINAME FROM 6N-8N BETWEEN 51W-56W. ...DISCUSSION... GULF OF MEXICO... TROPICAL STORM DON CONTINUES TO TRACK W-NW TOWARDS THE SOUTHERN TEXAS COASTLINE. SEE ABOVE. BROWNSVILLE AND MOSAIC DOPPLER RADAR IMAGERY WITH LIGHTNING DATA INDICATE CONVECTION OVER BROWNSVILLE TEXAS WITH STRONGER CONVECTION FURTHER S OVER NE MEXICO. ELSEWHERE...A 1018 MB HIGH IS OVER THE NE GULF OF MEXICO NEAR 29N84W PRODUCING FAIR WEATHER. CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN. SEE ABOVE. THIS AREA OF PRECIPITATION AND MOISTURE IS EXPECTED TO SHIFT WESTWARD OVER THE NEXT 24 HOURS WITH THE POTENTIAL FOR LOCALLY HEAVY RAINFALL AND POSSIBLE FLASH FLOODING ACROSS CENTRAL AMERICA. AN AREA OF SCATTERED MODERATE CONVECTION IS ALSO OVER N COLOMBIA...THE SW CARIBBEAN...AND NICARAGUA DUE TO THE MONSOON TROUGH. FURTHER N SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS INLAND OVER HONDURAS...GUATEMALA...AND S MEXICO BETWEEN 83W-100W. ATLANTIC OCEAN... THE MAJORITY OF THE ATLC BASIN REMAINS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED NEAR 40N35W. A RIDGE AXIS EXTENDS SW FROM THE HIGH TO 30N56W THEN CONTINUES WESTWARD ALONG 30N TO THE FLORIDA PENINSULA. ELSEWHERE...THE TROPICAL WAVES ARE THE PREDOMINATE WEATHER PRODUCERS IN THE BASIN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA