Hurricane Irma Intermediate Advisory Number 45A NWS National Hurricane Center Miami FL AL112017 800 AM EDT Sun Sep 10 2017 …CENTER OF IRMA ABOUT TO MAKE LANDFALL IN THE LOWER FLORIDA KEYS… SUMMARY OF 800 AM EDT…1200 UTC…INFORMATION LOCATION…24.5N 81.5W ABOUT 20 MI…30 KM ESE OF KEY WEST FLORIDA ABOUT 110 MI…180 KM S OF NAPLES FLORIDA MAXIMUM SUSTAINED WINDS…130 MPH…215 KM/H PRESENT MOVEMENT…NNW OR 330 DEGREES AT 8 MPH…13 KM/H MINIMUM CENTRAL PRESSURE…929 MB…27.43 INCHES
WATCHES AND WARNINGS CHANGES WITH THIS ADVISORY: The Government of Cuba has discontinued the Hurricane Warning for the Cuban provinces of Ciego de Avila, Sancti Spiritus, and Villa Clara.
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 Cuba and 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 AM EDT (1200 UTC),
the center of Hurricane Irma was located near latitude 24.5 North, longitude 81.5 West. Irma is moving toward the north-northwest near 8 mph (13 km/h), and 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 through the Florida Keys and near 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 wind gust to 89 mph (143 km/h) was recently measured at the Key West National Weather Service Forecast Office. Sustained winds of 46 mph (74 km/h) with a gust to 72 mph (117 km/h) was recently reported at Tamiami Airport in West Kendall, Florida. The estimated minimum central pressure is 929 mb (27.43 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. Northern coast of Cuba in the warning area…5 to 10 ft WIND: Hurricane conditions are expected to continue within the hurricane warning area along the north coast of Cuba through this morning. Hurricane conditions are spreading 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 conditions are possible in the watch area in the Northwestern Bahamas today.
RAINFALL: Additional 3 to 6 inches, isolated 10 inches. Western Bahamas…Additional 2 to 4 inches, isolated 6 inches. The Florida Keys…15 to 20 inches, isolated 25 inches. The southern Florida peninsula…10 to 15 inches, isolated 20 inches. The remainder of the Florida peninsula and southeast Georgia…8 to 12 inches, isolated 16 inches. The rest of Georgia, eastern Florida Panhandle, southern and western South Carolina, and western North Carolina…3 to 6 inches, isolated 10 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.
NEXT ADVISORY ————- Next complete advisory at 1100 AM EDT. $$ Forecaster Pasch NNNN
