000 WTNT34 KNHC 200534 TCPAT4 BULLETIN Potential Tropical Cyclone Four Intermediate Advisory Number 2A NWS National Hurricane Center Miami FL AL042022 100 AM CDT Sat Aug 20 2022 ...HEAVY RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS ACROSS PORTIONS OF SOUTH TEXAS AND NORTHEASTERN MEXICO THROUGH TONIGHT... SUMMARY OF 100 AM CDT...0600 UTC...INFORMATION ---------------------------------------------- LOCATION...22.2N 95.5W ABOUT 275 MI...445 KM SSE OF MOUTH OF THE RIO GRANDE MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...1009 MB...29.80 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * The Gulf coast of Mexico from Boca de Catan northward to the Mouth of the Rio Grande * The Lower Texas coast from Port Mansfield southward to the Mouth of the Rio Grande A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case within the next 24 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 100 AM CDT (0600 UTC), the disturbance was centered near latitude 22.2 North, longitude 95.5 West. The system is moving toward the northwest near 14 mph (22 km/h), and this motion is expected to continue for the next couple of days. The disturbance is expected to reach the coast of northeastern Mexico this evening and then move across the Rio Grande Valley tonight and Sunday. Maximum sustained winds remain near 35 mph (55 km/h) with higher gusts. Slow strengthening is expected until the system reaches the coast, and the disturbance is forecast to become a tropical storm later today. * Formation chance through 48 hours...high...70 percent. * Formation chance through 5 days...high...70 percent. The estimated minimum central pressure is 1009 mb (29.80 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Potential Tropical Cyclone Four can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4 and WMO header WTNT44 KNHC. WIND: Tropical storm conditions are expected to occur in the warning area beginning this afternoon or evening. RAINFALL: The disturbance is expected to produce total rainfall amounts of 3 to 6 inches, with isolated totals of 8 inches, along the eastern coast of Mexico from the northern portions of the state of Veracruz across the state of Tamaulipas to Nuevo Leon through today. Rainfall of 2 to 4 inches will be possible in South Texas through tonight with continuing uncertainty in how far north and west these amounts will be realized. The potential exists for life-threatening mudslides in the mountains of Mexico and life-threatening flash flooding elsewhere along the track of the disturbance. STORM SURGE: The combination of 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... Mouth of Rio Grande to Port Mansfield TX...1-2 ft 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. Storm surge could raise water levels by as much as 1 to 2 feet above normal tide levels along the immediate coast of northeastern Mexico near and to the north of where the center makes landfall. SURF: Swells generated by this system are forecast to affect eastern Mexico and southern Texas this weekend. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 400 AM CDT. $$ Forecaster Berg