538 
 WTPZ41 KNHC 012054
 TCDEP1
 
 Hurricane Norman Discussion Number  19
 NWS National Hurricane Center Miami FL       EP162018
 200 PM PDT Sat Sep 01 2018
 
 Since the previous advisory, a well-defined closed eye has remained
 apparent in microwave satellite data, and a cloud-filled eye has
 appeared in visible satellite imagery during the past couple of
 hours. Satellite intensity estimated haven't changed since the
 previous advisory, so the initial intensity remains 90 kt, which is
 supported by a 1501Z SATCON estimate of 88 kt and a Dvorak CI value
 of T5.0/90 kt.
 
 Norman's initial motion estimate is now 275/12 kt based on microwave
 and visible satellite eye position estimates. There are
 no significant changes to the previous track forecast and reasoning.
 The hurricane is expected to be steered by a strong deep-layer
 subtropical ridge to the north, resulting in a westward motion for
 the next 12-24 hours, followed by a west-northwestward motion at a
 faster forward speed. The latest model guidance is tightly packed
 about the previous forecast track through 96 hours, with much less
 divergence after that compared to previous model runs. Therefore,
 the new forecast track is essentially just an extension of the
 previous advisory track, and lies close to a blend of the HCCA,
 FSSE, and TVCE consensus track models.
 
 The GFS and ECMWF models are forecasting the 15-20 kt of vertical
 wind shear that has been affecting Norman to steadily decrease for
 the next 60-72 hours, possibly becoming near zero if the ECMWF
 upper-level wind forecasts verify. Since the hurricane is expected
 to remain over 27 deg C and warmer SSTs for the next 48 hours, only
 slow weakening is forecast and that is due mainly to occasional
 intrusions of drier and more stable air coming in from the
 northwest, where a large field of cold-air stratocumulus clouds is
 currently lurking close by. The HWRF and HMON models continue to
 forecast Norman to re-strengthen into a major hurricane during the
 next 24 hours, but this scenario is being discounted at this time
 due to Norman's proximity to the aforementioned stratocumulus cloud
 field.  By 72 hours, increasing southwesterly shear and cooler SSTs
 should combine to induce more significant weakening. The NHC
 intensity forecast is similar to the HCCA and IVCN consensus model
 forecasts.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  01/2100Z 16.3N 125.1W   90 KT 105 MPH
  12H  02/0600Z 16.6N 127.0W   90 KT 105 MPH
  24H  02/1800Z 17.4N 130.1W   85 KT 100 MPH
  36H  03/0600Z 18.2N 133.2W   85 KT 100 MPH
  48H  03/1800Z 19.1N 136.5W   80 KT  90 MPH
  72H  04/1800Z 20.4N 142.0W   70 KT  80 MPH
  96H  05/1800Z 21.4N 146.4W   65 KT  75 MPH
 120H  06/1800Z 22.2N 149.6W   60 KT  70 MPH
 
 $$
 Forecaster Stewart