ZCZC HFOTCDCP1 ALL TTAA00 PHFO DDHHMM Hurricane Hector Discussion Number 41 NWS Central Pacific Hurricane Center Honolulu HI EP102018 500 AM HST Fri Aug 10 2018 Hector has been showing some signs of fluctuations of intensity early this morning. The eye was less distinct earlier this morning, but it is showing signs of becoming somewhat better defined during the past couple of hours. All of the satellite fix agencies (PHFO, SAB and JTWC) continued to indicate the subjective Dvorak intensity estimates are T6.0/115 kt. The latest UW/CIMSS ADT is T5.8/110 kt. Based on a blend of this guidance, the initial intensity will be kept at 115 kt. Hector's latest movement appears to toward the west-northwest, or 285 degrees, at 14 kt. This motion is expected to continue today as Hector continues to be steered by a mid-level ridge located to the north-northeast. The western end of this ridge is forecast to weaken as a mid-level low pressure system develops near the International Dateline from tonight through this weekend. This is expected to result in a turn toward the northwest starting tonight, and continuing into early next week. The current forecast mostly follows the previous advisory package though 72 hours. After that, the latest forecast track is shifted slightly to the left on days 4 and 5. These subtle changes in the track were due to nudging toward the HWRF, as well as the consensus models, such as TVCN and GFEX. The latest intensity forecast is indicating nearly steady state conditions today and tonight. Note that there may be slight fluctuations in intensity during the next 12 to 24 hours, but Hector will likely remain a powerful hurricane through tonight. After that, we are expecting gradual weakening from 36 through 48 hours. The weakening trend is more significant beyond 48 hours as Hector moves into an area of increasing vertical wind shear, as well as cooler water temperatures. The current intensity forecast is also in line with HWRF, HMON, and CTC2, which have verified the best so far. These models also show a faster weakening after 48 hours, but this forecast again shows a more conservative weakening trend for now. As a result of Hector's west-northwest motion, the outer winds from the hurricane will be far removed from Johnston Island. Therefore, the Tropical Storm Watch is being discontinued. However, the latest wind speed probabilities continue to show portions of the Northwestern Hawaiian Islands, including Midway and Kure Atolls and the Papahanaumokuakea Marine National Monument west of French Frigate Shoals may require a Tropical Storm Watch later today or tonight. It is also possible that if Hector does not weaken this weekend as forecast, a Hurricane Watch may be required for some areas. Note that there is no threat to any of the main Hawaiian Islands from Kauai to the Big Island. FORECAST POSITIONS AND MAX WINDS INIT 10/1500Z 17.7N 165.9W 115 KT 130 MPH 12H 11/0000Z 18.5N 167.7W 115 KT 130 MPH 24H 11/1200Z 19.8N 169.8W 115 KT 130 MPH 36H 12/0000Z 21.3N 171.7W 105 KT 120 MPH 48H 12/1200Z 23.3N 173.8W 90 KT 105 MPH 72H 13/1200Z 27.0N 178.5W 70 KT 80 MPH 96H 14/1200Z 30.5N 176.5E 55 KT 65 MPH 120H 15/1200Z 33.5N 173.0E 45 KT 50 MPH $$ Forecaster Houston NNNN