972 WTNT31 KNHC 110855 TCPAT1 BULLETIN Hurricane Florence Advisory Number 48 NWS National Hurricane Center Miami FL AL062018 500 AM AST Tue Sep 11 2018 ...HURRICANE AND STORM SURGE WATCHES ISSUED FOR PORTIONS OF THE COASTS OF NORTH AND SOUTH CAROLINA... SUMMARY OF 500 AM AST...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...26.4N 64.1W ABOUT 410 MI...660 KM S OF BERMUDA ABOUT 975 MI...1570 KM ESE OF CAPE FEAR NORTH CAROLINA MAXIMUM SUSTAINED WINDS...140 MPH...220 KM/H PRESENT MOVEMENT...WNW OR 290 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...944 MB...27.88 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: A Storm Surge Watch has been issued for the east coast of the United States from Edisto Beach, South Carolina northward to the North Carolina-Virginia border, including the Pamlico and Albemarle Sounds. A Hurricane Watch has been issued for the east coast of the United States from Edisto Beach, South Carolina, northward to the North Carolina-Virginia border, including the Pamlico and Albemarle Sounds. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Watch is in effect for... * Edisto Beach South Carolina to the North Carolina-Virginia border * Albemarle and Pamlico Sounds, including the Neuse and Pamlico Rivers A Hurricane Watch is in effect for... * Edisto Beach South Carolina to the North Carolina-Virginia border * Albemarle and Pamlico Sounds Interests elsewhere in the southeastern and mid-Atlantic states should monitor the progress of Florence. Additional watches may be required later today. A Storm Surge Watch means there is a possibility of life- threatening inundation, from rising water moving inland from the coastline, in the indicated locations during the next 48 hours. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. A Hurricane Watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. DISCUSSION AND OUTLOOK ---------------------- At 500 AM AST (0900 UTC), the center of Hurricane Florence was located near latitude 26.4 North, longitude 64.1 West. Florence is moving toward the west-northwest near 15 mph (24 km/h). A west- northwestward to northwestward motion with a slight increase in forward speed are expected during the next couple of days. On the forecast track, the center of Florence will move over the southwestern Atlantic Ocean between Bermuda and the Bahamas through Wednesday, and approach the coast of North Carolina or South Carolina on Thursday. Maximum sustained winds are near 140 mph (220 km/h) with higher gusts. Florence is a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some strengthening is expected during the next day or so, and Florence is expected to be an extremely dangerous major hurricane through Thursday night. Hurricane-force winds extend outward up to 40 miles (65 km) from the center and tropical-storm-force winds extend outward up to 150 miles (240 km). The estimated minimum central pressure is 944 mb (27.88 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 has the potential to reach the following heights above ground if peak surge occurs at the time of high tide... Edisto Beach to Murrells Inlet...2-4 ft Murrells Inlet to Cape Fear...4-6 ft Cape Fear to Cape Lookout including The Neuse and Pamlico River...6-12 ft Cape Lookout to Ocracoke Inlet...5-8 ft Ocracoke Inlet to North Carolina/Virginia Border...3-5 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. RAINFALL: Florence is expected to produce total rainfall accumulations of 15 to 20 inches with isolated maxima to 30 inches near Florence's track over portions of North Carolina, Virginia, and northern South Carolina through Saturday. This rainfall may produce life-threatening flash flooding. WIND: Hurricane conditions are possible within the watch area by late Thursday or Thursday night, with tropical storm conditions possible by Thursday morning. SURF: Swells generated by Florence are affecting Bermuda and portions of the U.S. East Coast. 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 AST. $$ Forecaster Brown