740 WTPA44 PHFO 071439 TCDCP4 Hurricane Kiko Discussion Number 30 NWS Central Pacific Hurricane Center Honolulu HI EP112025 Issued by NWS National Hurricane Center Miami FL 500 AM HST Sun Sep 07 2025 Kiko remains a compact hurricane, although the eye has become less circular during the past few hours. Dvorak CI numbers from SAB, JTWC, and PHFO now range between 5.5-6.0 (102-115 kt), while objective numbers from UW-CIMSS are generally between 90-100 kt. Based on these estimates, the intensity is estimated to be about 100 kt. Another Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate Kiko around 8 AM HST/1800 UTC. The hurricane is on a steady west-northwestward trajectory of 300 degrees at 11 kt. A mid-level ridge lies north of Kiko, extending to about 150W, while a deep-layer low is located north of the Hawaiian Islands. The steering resulting from this pattern is expected to keep Kiko on a west-northwestward heading for the next 5 days, with some decrease in speed possible around Friday. Based on this motion, Kiko is expected to pass to the north of the Hawaiian Islands on Tuesday and Wednesday, and the most reliable track models are in good agreement on this scenario. The one main change in the forecast is that a good chunk of the guidance is showing a faster motion beyond 48 hours, and the new NHC forecast is therefore a little faster than the previous prediction at those forecast times, maintaining a forward speed of 12-13 kt through day 4. Kiko is already moving over cool waters of about 25 degrees Celsius, which is likely causing the current weakening trend. Although vertical shear is currently low, southwesterly shear of at least 20 kt is forecast to set in over Kiko in about 24 hours. Because of the hurricane's small size and it being embedded in a very dry surrounding environment, this shear is likely to hasten the weakening trend. The NHC intensity forecast closely follows the latest HCCA aid, dropping Kiko below hurricane strength just after 48 hours. While continued weakening is likely thereafter, there is some uncertainty as to whether Kiko will fall below tropical storm strength by day 5, as shown in the official forecast. If model trends continue to show some restrengthening, then subsequent advisories may keep tropical storm status through 5 days. Key Messages: 1. Kiko is forecast to pass north of the Hawaiian Islands on Tuesday and Wednesday. While the risk of direct impacts on the islands appears to be decreasing, interests there should continue to monitor Kiko's progress and the latest forecast. 2. Swells generated by Kiko are expected to begin reaching the Big Island and Maui later today. These swells will gradually build and are forecast to peak along east-facing exposures of the Hawaiian Islands late Monday through midweek, potentially producing life-threatening surf and rip currents. Listen for later advisories and possible warnings from the National Weather Service. FORECAST POSITIONS AND MAX WINDS INIT 07/1500Z 17.6N 144.4W 100 KT 115 MPH 12H 08/0000Z 18.4N 145.9W 95 KT 110 MPH 24H 08/1200Z 19.6N 148.1W 85 KT 100 MPH 36H 09/0000Z 20.9N 150.3W 75 KT 85 MPH 48H 09/1200Z 22.1N 152.7W 65 KT 75 MPH 60H 10/0000Z 23.2N 155.2W 55 KT 65 MPH 72H 10/1200Z 24.2N 157.7W 50 KT 60 MPH 96H 11/1200Z 26.0N 162.4W 40 KT 45 MPH 120H 12/1200Z 27.2N 165.7W 30 KT 35 MPH $$ Forecaster Berg
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