523 WTNT32 KNHC 031131 TCPAT2 BULLETIN Potential Tropical Cyclone Seven Intermediate Advisory Number 3A NWS National Hurricane Center Miami FL AL072018 800 AM EDT Mon Sep 03 2018 ...DISTURBANCE EXPECTED TO BECOME A TROPICAL STORM LATER TODAY... ...HEAVY RAINS LIKELY OVER PORTIONS OF SOUTH FLORIDA AND THE KEYS... SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION ---------------------------------------------- LOCATION...25.1N 80.5W ABOUT 5 MI...5 KM W OF KEY LARGO FLORIDA ABOUT 35 MI...60 KM E OF CAPE SABLE FLORIDA MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...1010 MB...29.82 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Watch is in effect for... * Mississippi-Alabama border westward to the Mouth of the Mississippi River A Tropical Storm Warning is in effect for... * Alabama-Florida border westward to east of Morgan City, Louisiana, including Lake Pontchartrain and Lake Maurepas Interests in the Florida Keys and the southern Florida peninsula 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 OUTLOOK ---------------------- At 800 AM EDT (1200 UTC), the disturbance was located by the Miami NOAA Doppler weather radar near latitude 25.1 North, longitude 80.5 West. The system is moving toward the west-northwest near 16 mph (26 km/h) and a west-northwestward to northwestward motion is expected over the next 72 hours. On the forecast track, the disturbance will pass over Florida Keys and the southern portion of the Florida peninsula this morning, move over the southeastern Gulf of Mexico this afternoon and evening, and reach the central Gulf Coast by late Tuesday or Tuesday night. Maximum sustained winds have increased to near 35 mph (55 km/h) with higher gusts. Gradual strengthening is forecast during the next 48 hours, and the disturbance is forecast to become a tropical storm later today. Conditions are expected to be conducive for development, and this system is forecast to become a tropical cyclone later today. * Formation chance through 48 hours...high...near 100 percent * Formation chance through 5 days...high...near 100 percent The estimated minimum central pressure is 1010 mb (29.82 inches). HAZARDS AFFECTING LAND ---------------------- 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... Destin Florida to the Mississippi-Alabama border...1 to 2 ft. Mississippi-Alabama border to the Mouth of Mississippi River...2 to 4 ft Mouth of the Mississippi River to the Louisiana-Texas border...1 to 2 ft The deepest water will occur along the immediate coast near and to the east of the landfall location, where the surge will be accompanied by large 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. RAINFALL: The disturbance is expected to produce total rain accumulations of 2 to 4 inches over the central and northwestern Bahamas, the Florida Keys, and South Florida through early Tuesday. Isolated maximum amounts of 8 inches are possible over the southern Florida peninsula. The disturbance is expected to produce total rain accumulations of 4 to 6 inches over southern Alabama, southern Mississippi and Louisiana, with isolated maximum amounts of 8 inches through early Thursday. These rainfall amounts may cause flash flooding. WIND: Tropical storm conditions are expected within portions of the warning area by late Tuesday. Tropical-storm-force wind gusts are possible today across portions of South Florida and the Florida Keys. NEXT ADVISORY ------------- Next complete advisory at 1100 AM EDT. $$ Forecaster Stewart