184 WTPZ41 KNHC 050256 TCDEP1 Hurricane Kiko Discussion Number 20 NWS National Hurricane Center Miami FL EP112025 500 PM HST Thu Sep 04 2025 The satellite presentation of Kiko has degraded considerably since the previous advisory, with the once warm and nearly cloud free eye, now obscured by a central dense overcast with cloud top temperatures of -65 to -80C. Given the mostly favorable environment that the cyclone is traversing, it is likely that Kiko is once again undergoing an eyewall replacement. The most recent subjective Dvorak current intensity estimates from TAFB and SAB were 6.0/115 kt and 5.5/102 kt respectively, while the objective estimates from UW-CIMSS have ranged between 101 and 117 kt during the past several hours. Based on a blend of these data and accounting for the degradation in satellite appearance, the initial intensity has been lowered to 110 kt for this advisory, and Kiko is now a category 3 hurricane. Kiko is moving just north of due west, or 275 degrees, at 8 kt. A gradual turn toward the west-northwest is expected tonight and Friday, as the western extent of a subtropical ridge to the north of the cyclone is eroded by developing upper-level low north of Hawaii. This general motion along with a gradual increase in forward speed is forecast to continue over the weekend and through early next week, as Kiko moves along the southwest periphery of the subtropical ridge to the northeast and toward a westward moving upper-level low to the north and northwest of the Hawaiian Islands. The latest track forecast is very close to the previous forecast through 60 hours, and slightly to the north of the previous forecast for days 3 through 5, following the latest guidance trends. The track forecast is closest to the TVCE consensus aid, and is to the south of the HCCA and FSSE consensus aids. Kiko will remain over warm waters of 27–28C for the next 24 hours, while influenced by light northeasterly vertical wind shear and in a somewhat drier than optimal mid-level environment. Despite the dry mid-level airmass, the mostly favorable environment could lead to some slight intensification tonight and Friday, provided that the eyewall replacement cycle which is likely ongoing, completes. Beyond 24 hours through day 3, Kiko will move over slightly cooler waters of 26 to 27C and into a drier mid-level environment with humidity levels below 50 percent. Despite very light vertical wind shear, these less favorable conditions should lead to gradual weakening of the cyclone. By days 4 and 5, Kiko will be moving over cooler water near or slightly below 26C, with west-southwesterly vertical wind shear ramping up to more than 30 kt by day 5, while mid-level moisture also plummets below 40 percent. The increasingly hostile environment should lead to rapid weakening of Kiko as the cyclone approaches the Hawaiian Islands from the east-southeast. The official intensity forecast has been lowered slightly from the previous advisory cycle, but remains on the higher end or slightly above the intensity aids through day 3 due to the continued potential for Kiko to develop annular characteristics. The intensity forecast then trends closer to the intensity consensus aid HCCA by days 4 and 5, with Kiko forecast to be a tropical storm by day 5 as it nears the eastern end of the Hawaiian Island chain. Key Messages: 1. Kiko is forecast to approach the Hawaiian Islands during the early to the middle portion of next week. The risk of direct impacts from wind and rainfall is increasing. However, it is too soon to determine the exact location or magnitude of these impacts, and interests there should continue to monitor the progress of this storm. FORECAST POSITIONS AND MAX WINDS INIT 05/0300Z 13.9N 135.4W 110 KT 125 MPH 12H 05/1200Z 14.2N 136.6W 120 KT 140 MPH 24H 06/0000Z 14.7N 138.5W 115 KT 130 MPH 36H 06/1200Z 15.3N 140.4W 110 KT 125 MPH 48H 07/0000Z 16.0N 142.2W 105 KT 120 MPH 60H 07/1200Z 16.7N 144.2W 100 KT 115 MPH 72H 08/0000Z 17.6N 146.2W 95 KT 110 MPH 96H 09/0000Z 19.3N 150.3W 75 KT 85 MPH 120H 10/0000Z 21.0N 154.7W 50 KT 60 MPH $$ Forecaster Jelsema (CPHC)
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