700 WTPZ45 KNHC 040845 TCDEP5 Hurricane Hector Discussion Number 15 NWS National Hurricane Center Miami FL EP102018 200 AM PDT Sat Aug 04 2018 Hector has maintained an impressive satellite presentation so far this morning. The clear eye of the major hurricane is surrounded by a ring of cloud tops colder than -75 deg C and its outflow has become well established in all quadrants. Recent satellite intensity estimates from TAFB, SAB, and the UW-CIMSS ADT are in good agreement and support an initial intensity of 105 kt. The hurricane will remain in a favorable environment for the next 48 to 72 h, so the NHC forecast keeps Hector as a fairly steady-state major hurricane, close to the HWRF model. In reality, while recent SSMIS and AMSU microwave data do not suggest that another eyewall replacement cycle is imminent, it would not be surprising if one did occur sometime in the next couple of days, causing the cyclone to at least briefly weaken. Hector's small size could also make it particularly prone to short-term fluctuations in intensity, up or down, like the one observed yesterday. By day 4, Hector is forecast to move over somewhat cooler SSTs, and into a drier environment, so gradual weakening is anticipated. Confidence in this portion of the forecast is fairly low since there large spread in the intensity guidance. Hector has continued to move steadily westward, and the initial motion estimate is 270/10 kt. A large subtropical ridge to the north should steer the hurricane generally westward through the entire forecast period. There is still uncertainty as to how much latitude Hector will gain in the 2 to 4 day time frame due to a slight weakness in the ridge, however the spread of the track guidance has generally decreased since yesterday. The official track forecast has been nudged very slightly northward, in line with the latest consensus guidance, but overall is very similar to the previous advisory. There is the potential for Hector to affect portions of the Hawaiian Islands by the middle of next week, but it is too soon to specify the magnitude of any impacts or where they could occur. This is a good time for everyone in the Hawaiian Islands to ensure they have their hurricane plan in place. For additional information on any potential local impacts from Hector in Hawaii, please refer to products issued by the NWS Weather Forecast Office in Honolulu at http://www.prh.noaa.gov/hnl. FORECAST POSITIONS AND MAX WINDS INIT 04/0900Z 14.3N 131.7W 105 KT 120 MPH 12H 04/1800Z 14.3N 133.2W 110 KT 125 MPH 24H 05/0600Z 14.5N 135.3W 110 KT 125 MPH 36H 05/1800Z 14.7N 137.6W 110 KT 125 MPH 48H 06/0600Z 15.0N 140.1W 110 KT 125 MPH 72H 07/0600Z 16.0N 145.8W 100 KT 115 MPH 96H 08/0600Z 16.5N 151.5W 90 KT 105 MPH 120H 09/0600Z 17.0N 157.5W 80 KT 90 MPH $$ Forecaster Zelinsky