BULLETIN Hurricane Irma Advisory Number 46 NWS National Hurricane Center Miami FL AL112017 1100 AM EDT Sun Sep 10 2017
...IRMA HEADED FOR THE SOUTHWEST FLORIDA COAST... ...WINDS CONTINUE TO INCREASE OVER SOUTH FLORIDA...
SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...25.0N 81.5W ABOUT 80 MI...125 KM SSE OF NAPLES FLORIDA ABOUT 115 MI...180 KM SSE OF FT. MYERS FLORIDA MAXIMUM SUSTAINED WINDS...130 MPH...215 KM/H PRESENT MOVEMENT...N OR 350 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...933 MB...27.55 INCHES
WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY:
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 * Cuban provinces of Matanzas and La Habana
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 Watch 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 1100 AM EDT (1500 UTC), the center of Hurricane Irma was located near latitude 25.0 North, longitude 81.5 West. Irma is moving toward the north near 9 mph (15 km/h, and a north-northwestward motion with an increase in forward speed is expected later today, with that motion continuing through Monday. On the forecast track, the eye of Irma should move over the Lower Florida Keys shortly, and then move near or over the west coast of the Florida Peninsula later today through tonight. Irma should then move inland over northern Florida and southwestern Georgia Monday afternoon.
Maximum sustained winds are near 130 mph (215 km/h) with higher gusts. Irma is a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale. While weakening is forecast, Irma is expected to remain a powerful hurricane while it moves near or along the west coast of Florida.
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). A 120 mph (193 km/h) gust was recently reported at the National Key Deer Refuge in Big Pine Key. A sustained wind of 62 mph (100 km/h) with a gust of 94 mph (151 km/h) was reported at the Federal Aviation Administration station at Miami International Airport. A pressure of 940 mb (27.75 inches) was measured in the calm of the eye on Upper Sugarloaf Key.
The minimum central pressure reported by an Air Force Hurricane Hunter aircraft is 933 mb (27.55 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 Ana 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...2 to 4 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.
The combination of a life-threatening storm surge and large breaking waves will raise water levels ABOVE NORMAL TIDE LEVELS by the following amounts within the hurricane warning area near and to the north of the center of Irma. Near the coast, the surge will be accompanied by large and destructive waves.
Water levels along the north coast of Cuba will gradually subside today.
WIND: Hurricane conditions are expected to continue within the hurricane warning area along the north coast of Cuba through this morning. Hurricane conditions are continuing across portions of the Florida Keys and southern Florida. 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 possible in the watch area in the Northwestern Bahamas today.
RAINFALL: Irma is expected to produce the following rain accumulations through Wednesday:
Western Cuba...Additional 1 to 3 inches, isolated 5 inches. Western Bahamas...Additional 2 to 4 inches, isolated 6 inches. The Florida Keys...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. Eastern Alabama and southern Tennessee...2 to 5 inches.
In all areas this rainfall may cause life-threatening flash floods and, in some areas, mudslides.
TORNADOES: Tornadoes are possible through tonight, mainly across southern, central, and eastern portions of the Florida Peninsula.
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.