Hurricane Nolo Forecast Discussion
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319 WTPA42 PHFO 250252 TCDCP2 Hurricane Nolo Discussion Number 18 NWS Central Pacific Hurricane Center Honolulu HI EP152026 Issued by NWS National Hurricane Center Miami FL 500 PM HST Thu Sep 24 2026 Nolo's structure on satellite imagery continues to gradually improve with a banding-type eye trying to develop on visible satellite imagery. The Air Force Reserve Hurricane Hunters have been flying through Nolo this afternoon, and found a peak flight-level wind of 71 kt and a minimum central pressure down to 984 mb in their most recent fix. These values are enough to upgrade Nolo to a hurricane this advisory, with an initial intensity of 65 kt. The storm is finally moving more consistently to the north-northeast with an estimated motion at 020 degrees at 4 kt. There is little change to the track reasoning this cycle, with a deep-layer trough located to the northwest of Nolo helping to steer it slowly to the north-northeast over the next 24-36 h. Thereafter, this trough cuts off to the west of the Hawaiian islands and moves westward out of the way, allowing mid-level ridging to build back in north of Nolo. The net result of this synoptic change is that Nolo is expected to make a sharp turn to the west, or even west-southwest in the 48-72 h time frame. However, the aforementioned cutoff low still limits how far west this mid-level ridging is able to extend, and Nolo will likely begin to gain latitude in the day 4-5 day time frame. The track guidance has made a rather substantial southward shift compared to the previous cycle, and the NHC track forecast has been shifted southward, though it remains on the northern side of the guidance envelope. This track forecast lies closest to the Google DeepMind ensemble mean (GDMI) which is actually a northern outlier this cycle, so it's possible future southward adjustments may be necessary. Even though Nolo is now a hurricane, the Air Force Reconnaissance aircraft has yet to report a closed eyewall in either of its fixes through the hurricane, and the wind field is a little bit on the broader side. However, environmental conditions appear quite favorable with low shear, sufficently warm sea-surface temperatures and enough deep-layer moisture to support robust intensification. The NHC intensity forecast continues to forecast significant intensification, and now shows a peak intensity of 115 kt as Nolo turns westward in the 48-72 h time frame. This intensity forecast is a blend of the latest HFIP Corrected Consensus Approach (HCCA) and HAFS-A/B runs, even though the HCCA remains the highest outlier in the intensity guidance this cycle. At long range, vertical wind shear is expected to increase, and the NHC intensity shows weakening beginning by day 5. Key Messages: 1. Nolo is expected to pass near or just south of the Big Island of Hawaii on Saturday as a major hurricane. Tropical storm conditions are expected to begin on the Big Island Friday night with hurricane conditions possible on Saturday, particularly in areas of steep terrain. Residents should follow advice given by local officials, including evacuating if told to do so. 2. The time to finish preparations for significant heavy rain and flooding impacts on the Big Island is now as heavy rain increases in both coverage and intensity today and Friday. Periods of heavy rain are expected to continue across the Big Island and Maui through the weekend. Life-threatening, catastrophic flooding and mudslides are possible, especially in areas of steep terrain across the eastern and southern portions of the Big Island and Maui. Across the remainder of Hawaii, lesser rainfall totals are expected, with isolated flooding possible. 3. Large and damaging waves are likely along portions of the Big Island's coastline into the weekend. 4. A Tropical Storm Watch is in effect for Maui County where tropical storm conditions are possible beginning on Saturday. Interests elsewhere in Hawaii should closely monitor the latest forecast updates and ensure that they have their preparedness plans in place. FORECAST POSITIONS AND MAX WINDS INIT 25/0300Z 15.1N 155.9W 65 KT 75 MPH 12H 25/1200Z 15.7N 155.6W 75 KT 85 MPH 24H 26/0000Z 16.6N 155.3W 85 KT 100 MPH 36H 26/1200Z 17.1N 155.4W 95 KT 110 MPH 48H 27/0000Z 17.0N 156.1W 100 KT 115 MPH 60H 27/1200Z 16.9N 157.7W 110 KT 125 MPH 72H 28/0000Z 16.9N 159.7W 115 KT 130 MPH 96H 29/0000Z 18.6N 163.0W 115 KT 130 MPH 120H 30/0000Z 21.7N 164.8W 90 KT 105 MPH $$ Forecaster Papin