je.st
news
Hurricane Norman Forecast Discussion Number 16
2018-09-01 04:51:06| National Hurricane Center (East Pacific)
Issued at 800 PM PDT Fri Aug 31 2018 508 WTPZ41 KNHC 010251 TCDEP1 Hurricane Norman Discussion Number 16 NWS National Hurricane Center Miami FL EP162018 800 PM PDT Fri Aug 31 2018 Several recent microwave passes indicate that Norman continues to feel the effects of northeasterly shear, with the cyclone vertically titled and its upper-level core disrupted in the northern semicircle. Furthermore, the eye of the hurricane has disappeared on IR and visible imagery. Satellite intensity estimates from TAFB and SAB have also decreased since the previous advisory, and therefore, the initial intensity has been decreased to 105 kt, and this value could be a little generous. Model guidance continues to indicate moderate northeasterly shear over the cyclone for the next day or so, which should cause the gradual weakening to continue. Thereafter, the shear is forecast to lessen somewhat, but the cyclone is expected to begin entraining dry air from its surrounding environment. There may be some time between 24-48 hours when the lessening shear and warm SSTs could overcome the drier air in the environment to allow for either a steadying of intensity or perhaps even some slight re-strengthening. Beyond 48 hours, however, the environment is forecast to become even drier, which should induce another weakening trend. The NHC intensity forecast has been changed little through 24 h, but now shows a leveling off of the intensity from 24-48 h. Steady weakening is still anticipated beyond that time. The initial motion is estimated to be west-southwest, or 250/7 kt. Mid- to upper-level ridging that extends west-southwestward from the Baja California peninsula to just northwest of the cyclone should steer Norman west-southwestward for the next several hours. By Saturday morning, the ridge should begin to become oriented more east-to-west then southeast-to-northwest by Sunday. This will cause the system to be steered on a more westward then west-northwestward track with an increase in forward speed over the weekend and into early next week. The NHC track forecast has been shifted slightly left and is a little faster than the previous advisory. This forecast is generally between the previous NHC forecast and the consensus guidance track. Based on this forecast, Norman is expected to move into the central Pacific basin by Tuesday. FORECAST POSITIONS AND MAX WINDS INIT 01/0300Z 16.3N 122.2W 105 KT 120 MPH 12H 01/1200Z 16.2N 123.6W 95 KT 110 MPH 24H 02/0000Z 16.4N 125.9W 90 KT 105 MPH 36H 02/1200Z 17.0N 128.7W 90 KT 105 MPH 48H 03/0000Z 17.7N 131.8W 90 KT 105 MPH 72H 04/0000Z 19.1N 138.0W 80 KT 90 MPH 96H 05/0000Z 20.3N 142.7W 70 KT 80 MPH 120H 06/0000Z 21.2N 146.3W 65 KT 75 MPH $$ Forecaster Cangialosi/Latto
Tags: number
discussion
forecast
norman
Category:Transportation and Logistics