118 WTNT31 KNHC 172335 TCPAT1 BULLETIN Potential Tropical Cyclone One Intermediate Advisory Number 1A NWS National Hurricane Center Miami FL AL012024 700 PM CDT Mon Jun 17 2024 ...SYSTEM FORECAST TO CAUSE HEAVY RAINS AND COASTAL FLOODING IN NORTHEASTERN MEXICO AND TEXAS BEGINNING ON TUESDAY... SUMMARY OF 700 PM CDT...0000 UTC...INFORMATION ---------------------------------------------- LOCATION...20.5N 93.0W ABOUT 375 MI...620 KM SE OF LA PESCA MEXICO ABOUT 465 MI...750 KM SE OF BROWNSVILLE TEXAS MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...NNW OR 345 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Watch is in effect for... * The Texas coast from Port O'Connor southward to the mouth of the Rio Grande * The northeastern coast of Mexico south of the mouth of the Rio Grande to Boca de Catan. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. For storm information specific to your area in the United States, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. For storm information specific to your area outside of the United States, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 700 PM CDT (0000 UTC), the poorly defined disturbance was centered near latitude 20.5 North, longitude 93.0 West. The system is moving toward the north-northwest near 7 mph (11 km/h), and this general motion is expected to continue through Tuesday. A turn toward the west-northwest is expected Tuesday night or Wednesday, and system is likely to approach the western Gulf coast late Wednesday. Maximum sustained winds remain near 40 mph (65 km/h) with higher gusts. The disturbance is forecast to to become a tropical storm by Wednesday. * Formation chance through 48 hours...high...80 percent. * Formation chance through 7 days...high...80 percent. The disturbance is quite large with tropical-storm-force winds extending outward up to 290 miles (465 km) to the northeast of the center. The estimated minimum central pressure is 999 mb (29.50 inches) based on Air Force Reserve dropsonde data. HAZARDS AFFECTING LAND ---------------------- Key messages for Potential Tropical Cyclone One can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT1 and WMO header WTNT41 KNHC. RAINFALL: Potential Tropical Cyclone One is expected to produce rainfall totals of 5 to 10 inches across northeast Mexico into southeastern Texas, with maximum totals of 15 inches possible. This rainfall will likely produce flash and urban flooding along with new and renewed river flooding. Mudslides are also possible in areas of higher terrain across northeast Mexico. For a complete depiction of forecast rainfall and flash flooding associated with Potential Tropical Cyclone One, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_at1.shtml?rainqpf and the Flash Flood Risk graphic at hurricanes.gov/graphics_at1.shtml?ero STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide... Sargent, TX to Sabine Pass, TX...2-4 ft Galveston Bay...2-4 ft Mouth of the Rio Grande, TX to Sargent, TX...1-3 ft Sabine Pass, TX to Vermilion/Cameron Parish Line, LA...1-3 ft The deepest water will occur along the immediate coast near and to the north of the landfall location, where the surge will be accompanied by large and dangerous waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office. For a complete depiction of areas at risk of storm surge inundation, please see the National Weather Service Peak Storm Surge Graphic, available at hurricanes.gov/graphics_at1.shtml?peakSurge. In Mexico, minor coastal flooding is possible north of where the center of the disturbance crosses the coast in areas of onshore winds. WIND: Tropical storm conditions are possible within the watch area by Wednesday. NEXT ADVISORY ------------- Next complete advisory at 1000 PM CDT. $$ Forecaster Blake