Issued at 500 AM AST Thu Sep 19 2019 000WTNT44 KNHC 190853TCDAT4Hurricane Humberto Discussion Number 27NWS National Hurricane Center Miami FL AL092019500 AM AST Thu Sep 19 2019Flight-level and surface wind observations reported by Air ForceReserve Hurricane Hunter aircraft exiting Humberto a couple of hoursago indicated that the maximum sustained winds have increased to 110kt. However, weakening is expected to commence soon.Humberto's extratropical transition continues as a high amplitude PVtongue, noted in the GOES-16 water vapor imagery, and associated dryair, digs into the backside of the cyclone. The large-scale models,as well as the FSU Cyclone Phase Evolution forecast, indicate thatthe process will be completed in less than 36 hours. Afterward,gradual weakening is expected until the extratropical low isabsorbed by another larger low pressure system, moving out ofAtlantic Canada, by the end of the forecast period. The NHCintensity forecast is basically an update of the previous forecastand is based on a blend of the global models beyond the 36 hourperiod.The initial motion is estimated to be northeastward, or 045/19 kt.Humberto is forecast to turn north-northeastward as the cyclonecompletes its extratropical transition, followed by a turnback toward the east-northeast within the strong deep-layermid-latitude westerlies. The NHC forecast is nudged a little to theleft of the previous advisory between the 36 and 72 hour periods,and is close to the NOAA HFIP HCCA consensus model.Key Messages:1. Storm surge and dangerous breaking waves, while diminishing,could cause coastal flooding today along the coast of Bermuda.2. Swells will continue to affect the northwestern Bahamas and thesoutheastern coast of the United States from east-central Florida toNorth Carolina during the next couple of days, creating life-threatening surf and rip current conditions.FORECAST POSITIONS AND MAX WINDSINIT 19/0900Z 35.2N 62.2W 110 KT 125 MPH 12H 19/1800Z 37.4N 60.0W 95 KT 110 MPH 24H 20/0600Z 39.9N 58.9W 75 KT 85 MPH 36H 20/1800Z 41.8N 57.4W 60 KT 70 MPH...POST-TROP/EXTRATROP 48H 21/0600Z 43.2N 53.4W 50 KT 60 MPH...POST-TROP/EXTRATROP 72H 22/0600Z 46.3N 36.4W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 23/0600Z...DISSIPATED$$Forecaster Roberts

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