| BULLETIN Hurricane Florence Advisory Number 57 NWS National Hurricane Center Miami FL AL062018 1100 AM EDT Thu Sep 13 2018 ...HEAVY RAINBANDS WITH TROPICAL-STORM-FORCE WINDS SPREADING ACROSS THE OUTER BANKS AND COASTAL SOUTHEASTERN NORTH CAROLINA... ...LIFE-THREATENING STORM SURGE AND RAINFALL EXPECTED... SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...33.4N 75.5W ABOUT 145 MI...230 KM ESE OF WILMINGTON NORTH CAROLINA ABOUT 195 MI...315 KM E OF MYRTLE BEACH SOUTH CAROLINA MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H PRESENT MOVEMENT...NW OR 315 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...955 MB...28.20 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 South Carolina to Duck North Carolina Albemarle and Pamlico Sounds, including the Neuse and Pamlico Rivers A Storm Surge Watch is in effect for... Edisto Beach South Carolina to South Santee River South Carolina North of Duck North Carolina to the North Carolina/Virginia border A Hurricane Warning is in effect for... South Santee River South Carolina to Duck North Carolina Albemarle and Pamlico Sounds A Hurricane Watch is in effect for... Edisto Beach South Carolina to South Santee River South Carolina A Tropical Storm Warning is in effect for... North of Duck North Carolina to Cape Charles Light Virginia Chesapeake Bay south of New Point Comfort Interests elsewhere in the southeastern and mid-Atlantic states should monitor the progress of Florence. A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline. 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. A Storm Surge Watch means there is a possibility of life- threatening inundation, from rising water moving inland from the coastline. A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area, in this case within the next 12 to 24 hours. Preparations to protect life and property should be nearing completion. 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. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM EDT (1500 UTC), data from an Air Force Reserve Unit Hurricane Hunter aircraft and NOAA Doppler weather radars from indicate that Florence was located near latitude 33.4 North, longitude 75.5 West. Florence is moving toward the northwest near 10 mph (17 km/h). This general motion, accompanied by a further decrease in forward speed, is expected to continue through today. A turn to the west-northwest and west at an even slower forward speed is expected tonight and Friday, and a slow west-southwestward motion is forecast Friday night and Saturday. On the forecast track, the center of Florence will approach the coasts of North and South Carolina later today, then move near or over the coast of southern North Carolina and northeastern South Carolina in the hurricane warning area tonight and Friday. A slow motion across portions of eastern South Carolina is forecast Friday night through Saturday night. Data from the aircraft and Doppler weather radars indicate that maximum sustained winds have decreased to near 105 mph (165 km/h) with higher gusts. Little change in strength is expected before the center reaches the coast, with weakening expected after the center moves inland. Florence is a large hurricane. Hurricane-force winds extend outward up to 80 miles (130 km) from the center and tropical-storm-force winds extend outward up to 195 miles (315 km). NOAA Buoy 41025, located near Diamond Shoals, North Carolina, recently reported a sustained wind of 54 mph (87 km/h). The latest minimum central pressure based on data from the aircraft is 955 mb (28.20 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... Cape Fear NC to Cape Lookout NC, including the Neuse, Pamlico, Pungo, and Bay Rivers...9-13 ft North Myrtle Beach SC to Cape Fear NC...6-9 ft Cape Lookout NC to Ocracoke Inlet NC...6-9 ft South Santee River SC to North Myrtle Beach SC...4-6 ft Ocracoke Inlet NC to Salvo NC...4-6 ft Salvo NC to North Carolina/Virginia Border...2-4 ft Edisto Beach SC to South Santee River SC...2-4 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 heavy and excessive rainfall in the following areas... Coastal North Carolina into far northeastern South Carolina...20 to 30 inches, isolated 40 inches. This rainfall will produce catastrophic flash flooding and prolonged significant river flooding. Remainder of South Carolina and North Carolina into southwest Virginia...6 to 12 inches, isolated 24 inches. WIND: Hurricane conditions are expected to reach the coast within the hurricane warning area this evening or early Friday. Tropical storm conditions are already moving onshore within the warning area. TORNADOES: A few tornadoes are possible in eastern North Carolina through Friday. SURF: Swells generated by Florence are affecting Bermuda, portions of the U.S. East Coast, and the northwestern and central Bahamas. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 200 PM EDT. Next complete advisory at 500 PM EDT. $$ Forecaster Stewart |