| http://www.nhc.noaa.gov/cyclones/ http://www.weather.gov/wrn/irma http://www.weather.gov/srh/tropical DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 800 AM EDT (1200 UTC), the center of Tropical Storm Irma was located near latitude 29.5 North, longitude 82.9 West. Irma is moving toward the north-northwest near 18 mph (30 km/h) and this motion is expected to continue through Tuesday. On the forecast track, the center of Irma will move near the northwestern coast of the Florida Peninsula this morning, cross the eastern Florida Panhandle into southern Georgia this afternoon, and move through southwestern Georgia and eastern Alabama tonight and Tuesday. Maximum sustained winds have decreased to near 70 mph (110 km/h) with higher gusts. Additional slow weakening is forecast, and Irma is expected to weaken to a tropical depression by Tuesday afternoon. Irma has a very large wind field. Hurricane-force winds extend outward up to 60 miles (95 km) mainly to the west of the center, and tropical-storm-force winds extend outward up to 415 miles (665 km). The estimated minimum central pressure is 970 mb (28.64 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...2 to 4 ft Captiva to Anna Maria Island...3 to 5 ft North Miami Beach to Cape Sable, including the Florida Keys...1 to 2 ft Anna Maria Island to Clearwater, including Tampa Bay...2 to 4 ft South Santee River to Fernandina Beach...4 to 6 ft Clearwater Beach to Ochlockonee River...4 t 6 ft Fernandina Beach to Jupiter Inlet...3 to 5 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: Tropical storm conditions will continue across portions of the central and northern Florida peninsula, and are spreading into southern Georgia. Tropical storm conditions should spread into the eastern Florida Panhandle today. Tropical storm conditions are also expected to spread northward across the remainder of the warning areas through today. Rainfall: Irma is expected to produce the following rain accumulations through Wednesday: The Florida Keys and southern Florida peninsula: additional 1 inch. Central Florida peninsula: additional 1 to 3 inches. Northern Florida peninsula and southern Georgia: additional 3 to 6 inches with storm total amounts of 8 to 15 inches. Central Georgia, eastern Alabama and southern South Carolina: 3 to inches, isolated 10 inches. Central Florida Panhandle, western Alabama, northern Mississippi, southern Tennessee, northern Georgia, northern South Carolina and western North Carolina: 2 to 4 inches. TORNADOES: A few tornadoes are possible across northeast Florida and southeast portions of Georgia and South Carolina through tonight. 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. |