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ZCZC MIATCPAT1 ALL TTAA00 KNHC DDHHMM BULLETIN Hurricane Irma Intermediate Advisory Number 47A NWS National Hurricane Center Miami FL AL112017 800 PM EDT Sun Sep 10 2017 ...IRMA MOVING NORTHWARD NEAR FT. MYERS... ...DANGEROUS STORM SURGES EXPECTED IN AREAS OF ONSHORE WINDS ALONG THE FLORIDA WEST COAST... SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION ---------------------------------------------- LOCATION...26.7N 81.7W ABOUT 15 MI...25 KM ENE OF FT. MYERS FLORIDA ABOUT 30 MI...50 KM SE OF PORT CHARLOTTE FLORIDA MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H PRESENT MOVEMENT...N OR 355 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...942 MB...27.82 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Warning is in effect for... * South Santee River southward to Jupiter Inlet * North Miami Beach southward around the Florida peninsula to the Ochlockonee River * Florida Keys * Tampa Bay A Hurricane Warning is in effect for... * Fernandina Beach southward around the Florida peninsula to Indian Pass * Florida Keys * Lake Okeechobee * Florida Bay A Hurricane Watch is in effect for... * North of Fernandina Beach to Edisto Beach A Tropical Storm Warning is in effect for... * West of Indian Pass to the Okaloosa/Walton County Line * North of Fernandina Beach to South Santee River A Tropical Storm Warning is in effect for... * Bimini and Grand Bahama A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline, during the next 36 hours in the indicated locations. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials. Interests elsewhere in the southeastern United States should monitor the progress of Irma. 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 the United States, please monitor products issued by your national meteorological service. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 800 PM EDT (0000 UTC), the center of Hurricane Irma was located by NOAA Doppler radar near latitude 26.7 North, longitude 81.7 West. Irma is moving toward the north near 14 mph (22 km/h), and a north-northwestward motion with an increase in forward speed is expected by tonight, with that motion continuing through Monday. On the forecast track, the eye of Irma should move near or over the west coast of the Florida Peninsula through Monday morning. Irma should then move inland over northern Florida and southwestern Georgia Monday afternoon. Maximum sustained winds have decreased to near 105 mph (165 km/h) with higher gusts. Although weakening is forecast, Irma is expected to remain a hurricane at least through Monday morning. Hurricane-force winds extend outward up to 80 miles (130 km) from the center, and tropical-storm-force winds extend outward up to 220 miles (350 km). The estimated minimum central pressure is 942 mb (27.82 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 is expected to reach the following HEIGHTS ABOVE GROUND if the peak surge occurs at the time of high tide... Cape Sable to Captiva...10 to 15 ft Captiva to Ana Maria Island...6 to 10 ft Card Sound Bridge through Cape Sable, including the Florida Keys... 5 to 10 ft Anna Maria Island to Clearwater Beach, including Tampa Bay... 5 to 8 ft North Miami Beach to Card Sound Bridge, including Biscayne Bay... 3 to 5 ft South Santee River to Fernandina Beach...4 to 6 ft Clearwater Beach to Ochlockonee River...4 to 6 ft Fernandina Beach to Jupiter Inlet...3 to 5 ft North of North Miami Beach to Jupiter Inlet...1 to 2 ft The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large and destructive 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. WIND: Hurricane conditions are continuing across portions of the southern Florida peninsula. Winds affecting the upper floors of high-rise buildings will be significantly stronger than those near ground level. Tropical storm and hurricane conditions are expected to spread northward across the remainder of the warning areas through Monday. Tropical storm conditions are expected in portions of the warning area in the Northwestern Bahamas this evening. RAINFALL: Irma is expected to produce the following rain accumulations through Wednesday: Western Bahamas...Additional 2 to 4 inches, isolated 6 inches. The Florida Keys...Additional 3 to 6 inches with storm total amounts from 15 to 20 inches, isolated 25 inches. Western Florida peninsula...10 to 15 inches, isolated 20 inches. Eastern Florida peninsula and southeast Georgia...8 to 12 inches, isolated 16 inches. The rest of Georgia, the eastern Florida Panhandle, southern and western South Carolina, and western North Carolina...3 to 8 inches, isolated 12 inches. Southern Tennessee, northern Mississippi and much of Alabama...2 to 5 inches. In all areas this rainfall may cause life-threatening flash floods. TORNADOES: Tornadoes remain possible through tonight, mainly across central and eastern portions of the Florida Peninsula and extreme southeast Georgia. THE EYE: Do not venture outside when the calm eye of the hurricane passes over, as dangerous winds will return very quickly when the eye moves away. SURF: Swells generated by Irma are affecting the southeast coast of the United States. 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 1100 PM EDT. $$ Forecaster Berg NNNN