000 WTNT44 KNHC 170232 TCDAT4 Hurricane Humberto Discussion Number 18 NWS National Hurricane Center Miami FL AL092019 1100 PM EDT Mon Sep 16 2019 Humberto continues to have an impressive overall appearance on satellite imagery, although the eye is a bit ragged looking. Earlier radar images from the NOAA P-3 aircraft showed that the eyewall was somewhat fragmented. A last-minute observation of 700-mb flight-level winds of 86 kt from the Air Force Hurricane Hunters, outbound to the west of the eye, is roughly consistent with a current intensity estimate of 80 kt. Humberto should continue to traverse warm waters for the next couple of days, and much of the numerical guidance shows intensification in the short term. Therefore the official forecast, like the previous one, continues to call for the system to become a major hurricane within the next day or so. This is similar to the intensity model consensus. By 48 hours, the shear should become very strong and a weakening trend will likely be underway. By day 5, if not sooner, the ECMWF global model shows the system embedded within a frontal zone so Humberto is forecast to be extratropical at that time. The eye has been wobbling over the past few hours, but a smoothed estimate of the motion is just north of east or 075/7 kt. Humberto should continue to move along the northern side of a subtropical ridge with a gradual increase in forward speed for the next couple of days. After that, the hurricane should turn northeastward and north-northeastward with some additional acceleration in response to a strong mid-tropospheric trough near Atlantic Canada. Around the end of the forecast period, the global models differ significantly as to how far north into the Atlantic Humberto will move. The official forecast leans toward the ECMWF and corrected consensus, HCCA, guidance. It is still too early to give a good estimate as to how close the core of the hurricane will come to Bermuda. Interests should not focus on the exact forecast track; only a slight deviation to the right could bring the center near or over the island. Large swells from Humberto will affect Bermuda by late Tuesday, and affect portions of the northwestern Bahamas and southeastern United States coast during the next couple of days. These swells are expected to produce dangerous surf conditions and life-threatening rip currents. See products issued by your local weather office and the Bermuda Weather Service for additional information. FORECAST POSITIONS AND MAX WINDS INIT 17/0300Z 30.3N 75.1W 80 KT 90 MPH 12H 17/1200Z 30.7N 74.0W 90 KT 105 MPH 24H 18/0000Z 31.1N 72.2W 95 KT 110 MPH 36H 18/1200Z 31.6N 70.0W 100 KT 115 MPH 48H 19/0000Z 32.8N 66.6W 90 KT 105 MPH 72H 20/0000Z 37.1N 60.7W 80 KT 90 MPH 96H 21/0000Z 40.5N 58.0W 65 KT 75 MPH 120H 22/0000Z 43.0N 50.0W 55 KT 65 MPH...POST-TROP/EXTRATROP $$ Forecaster Pasch