Issued at 500 PM EDT Thu Oct 11 2018 000WTNT44 KNHC 112053TCDAT4Tropical Storm Michael Discussion Number 21NWS National Hurricane Center Miami FL AL142018500 PM EDT Thu Oct 11 2018Satellite and radar data show that Michael's rain shield isbeginning to expand northward and northwestward, and that cooler anddrier air is starting to wrap around the western portion of thecirculation. These trends indicate that Michael's transition to anextratropical low has started. There have been recent observationsof 40 to nearly 45 kt sustained winds along the southeastern coastof North Carolina, so the initial intensity remains 45 kt. Littlechange in strength is expected through this evening, but Michael isforecast to quickly intensify after it completes extratropicaltransition and exits the east coast of the United States tonight.The official intensity forecast is based on guidance from the NOAAOcean Prediction Center.It should also be noted that an area of damaging wind gusts of up to50 kt has developed around the northwest side of the circulationover central North Carolina and Virginia this afternoon. As aresult, the gust factor has been increased in this advisory, as thisarea of strong winds will spread northward and eastward acrossportions of eastern Virginia and northeastern North Carolina thisevening and tonight.Michael is moving northeastward or 050/21 kt. The storm willcontinue to accelerate as it become further embedded within themid-latitude westerlies. The post-tropical cyclone will raceacross the north Atlantic during the next few days, before slowingdown late in the period before it weakens and dissipates. Thetrack guidance continues to be in good agreement and little changewas required from the previous NHC track forecast.Gale- to storm-force winds are expected over portions of theMid-Atlantic coast as Michael exits the U.S. east coast and becomespost-tropical. Non-tropical high wind watches, warnings, andadvisories have been issued by local NWS offices for wind hazards inthese areas north of Duck, North Carolina.Key Messages:1. Life-threatening flash flooding is occurring over portions ofNorth Carolina and southern Virginia and will continue through theevening.2. Damaging winds are spreading eastward across portions of centraland eastern North Carolina, and will continue through this evening.These winds have the potential to cause tree and structural damage.Strong winds are also expected over portions of southeasternVirginia and the Virginia Eastern Shore tonight as Michael becomespost-tropical.3. Dangerous storm surge is possible tonight along the sound side ofthe North Carolina Outer Banks from Ocracoke Inlet to Duck, where aStorm Surge Watch is in effect.FORECAST POSITIONS AND MAX WINDSINIT 11/2100Z 36.1N 78.8W 45 KT 50 MPH...INLAND 12H 12/0600Z 38.1N 74.7W 45 KT 50 MPH...POST-TROP/EXTRATROP 24H 12/1800Z 41.2N 66.5W 60 KT 70 MPH...POST-TROP/EXTRATROP 36H 13/0600Z 44.5N 55.5W 60 KT 70 MPH...POST-TROP/EXTRATROP 48H 13/1800Z 47.0N 42.0W 60 KT 70 MPH...POST-TROP/EXTRATROP 72H 14/1800Z 48.5N 17.5W 50 KT 60 MPH...POST-TROP/EXTRATROP 96H 15/1800Z 46.5N 7.0W 30 KT 35 MPH...POST-TROP/EXTRATROP120H 16/1800Z...DISSIPATED$$Forecaster Brown

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