147 WTNT44 KNHC 160237 TCDAT4 Hurricane Humberto Discussion Number 14 NWS National Hurricane Center Miami FL AL092019 1100 PM EDT Sun Sep 15 2019 700 mb flight-level wind data from a NOAA P-3 Hurricane Hunter aircraft investigating Humberto indicate that the system's intensity is now 65 kt. This is also supported by Dvorak classifications from TAFB and SAB, and it makes the cyclone the third hurricane of the 2019 Atlantic season. Humberto's cloud pattern has continued to gradually become better organized, with increasing coverage and intensity of deep convection, and pronounced upper-level outflow over the eastern semicircle of the circulation. The hurricane is expected to traverse warm Gulf Stream waters for the next several days, but the dynamical models forecast a significant increase in southwesterly vertical shear through 72 hours. In spite of the latter unfavorable factor, the numerical guidance generally shows intensification. This is likely at least partially due to some baroclinic forcing caused by a strong mid-latitude trough to the north and northeast of Humberto. The official forecast is a blend of the latest simple and corrected consensus models and is very similar to the previous one. Humberto continues to move very slowly and the latest aircraft and satellite center fixes indicate that the motion is now northeastward or 040/3 kt. The hurricane has just rounded the western periphery of a subtropical anticyclone and steering currents are likely to remain weak for the next couple of days. An east-northeastward track with a very gradual increase in forward speed is expected for much of the period while Humberto moves between the subtropical high and stronger westerlies associated with the trough to the north. The new NHC track forecast is a little slower than the previous one in 4-5 days, but not as slow as the latest ECMWF and GFS global model runs. Large swells from Humberto will affect portions of the northwestern Bahamas and southeastern United States coast during the next few days. These swells are expected to produce dangerous surf conditions and life-threatening rip currents. See products issued by your local weather office for additional information. FORECAST POSITIONS AND MAX WINDS INIT 16/0300Z 29.4N 77.6W 65 KT 75 MPH 12H 16/1200Z 29.8N 77.1W 70 KT 80 MPH 24H 17/0000Z 30.1N 76.0W 75 KT 85 MPH 36H 17/1200Z 30.5N 74.7W 80 KT 90 MPH 48H 18/0000Z 30.8N 73.0W 85 KT 100 MPH 72H 19/0000Z 31.8N 68.3W 95 KT 110 MPH 96H 20/0000Z 35.0N 63.3W 80 KT 90 MPH 120H 21/0000Z 39.0N 60.0W 60 KT 70 MPH $$ Forecaster Pasch