ZCZC MIATCPAT3 ALL TTAA00 KNHC DDHHMM BULLETIN Potential Tropical Cyclone Three Advisory Number 4 NWS National Hurricane Center Miami FL AL032017 1000 AM CDT Tue Jun 20 2017 ...TROPICAL STORM WARNING EXTENDED WESTWARD AND TROPICAL STORM WATCH ISSUED FOR THE UPPER TEXAS COAST... ...HEAVY RAINFALL ALONG MUCH OF THE GULF COAST REMAINS THE BIGGEST THREAT... SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...25.9N 90.5W ABOUT 265 MI...430 KM S OF MORGAN CITY LOUISIANA ABOUT 355 MI...565 KM SE OF GALVESTON TEXAS MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...NW OR 320 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The Tropical Storm Warning has been extended westward to High Island, Texas. A Tropical Storm Watch is in effect from west of High Island to San Luis Pass, Texas. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * High Island to the Mouth of the Pearl River A Tropical Storm Watch is in effect for... * West of High Island to San Luis Pass A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case within the next 24 to 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere along the U.S. Gulf Coast from the central Texas coast to the western Florida Panhandle should monitor the progress of this system. For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 1000 AM CDT (1500 UTC), the disturbance was centered near latitude 25.9 North, longitude 90.5 West. The system is moving toward the northwest near 10 mph (17 km/h) and this motion is expected to continue through Wednesday night. A turn toward the north-northwest is forecast early Thursday. On the forecast track, the disturbance is expected to be near the southwest Louisiana coast late Wednesday or Wednesday night, and move inland over western Louisiana and eastern Texas on Thursday. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Some slight strengthening is possible before the system reaches the coast. Satellite imagery shows that the center of the disturbance is gradually become better defined, and it is likely that the system will become a tropical or subtropical cyclone later today. * Formation chance through 48 hours...high...90 percent * Formation chance through 5 days...high...90 percent Tropical-storm-force winds extend outward up to 205 miles (335 km), mainly to the north and east of the center. The estimated minimum central pressure based on buoy data is 999 mb (29.50 inches). HAZARDS AFFECTING LAND ---------------------- WIND: Tropical storm conditions are expected to first reach the coast within the warning area later today and spread westward within the warning area through Wednesday. Tropical storm conditions are possible in the watch area on Wednesday. RAINFALL: The disturbance is expected to produce total rain accumulations of 6 to 9 inches with isolated maximum amounts of 12 inches over southeastern Louisiana, southern Mississippi, southern Alabama, and the Florida Panhandle through Thursday. Rainfall amounts of 3 to 5 inches with isolated maximum amounts of 6 inches can be expected farther west across southwest Louisiana into southeast Texas through Thursday. STORM SURGE: Inundation of 1 to 3 feet above ground level is possible along the coast in portions of the Tropical Storm Warning area. TORNADOES: A tornado or two is possible this afternoon and tonight from south-central Louisiana to the western Florida Panhandle. NEXT ADVISORY ------------- Next intermediate advisory at 100 PM CDT. Next complete advisory at 400 PM CDT. $$ Forecaster Brennan NNNN