Tropical Cyclone Discussion
716 WTPA42 PHFO 270255 TCDCP2 Hurricane Nolo Discussion Number 26 NWS Central Pacific Hurricane Center Honolulu HI EP152026 Issued by NWS National Hurricane Center Miami FL 500 PM HST Sat Sep 26 2026 Nolo is sending mixed signals about its organization in both satellite and aircraft data at this time. In satellite imagery, the central convective tops have cooled and become more symmetric around the center. However, as this has happened, the eye has become less distinct. In aircraft data, the Air Force Reserve Hurricane Hunter reported that the central pressure has dropped to near 969 mb. However, the maximum 700 mb flight-level winds reported so far are 77 kt, and the aircraft reported that the eyewall was ragged. Given the conflicting signals, the initial intensity is held at a somewhat uncertain 80 kt. The hurricane is now moving faster toward the west or 265/7 kt. A faster westward motion is expected for the next 24 h, keeping the core of the hurricane well south of the main Hawaiian Islands. After that, Nolo should turn northwestward between a ridge to the east and a mid- to upper-level low to the northwest of Hawaii, with this motion continuing until about the 72 h point. The dynamical models suggest the circulation of Nolo may merge with this low, with the resulting system continuing westward on the south side of a mid-level ridge to the north. The new forecast track is similar to the previous track and lies near the center of the track guidance envelope. Nolo is moving westward toward a pocket of higher ocean heat content southwest of the Hawaiian Islands, and the vertical wind shear is forecast to weaken during the next 24-36 h. This should allow some strengthening during this time, and the new intensity forecast follows the regional hurricane models in forecasting Nolo to become a major hurricane. It should be noted that while the SHIPS models are not as bearish on intensification as they were last night, they keep the system well below major hurricane strength. After 36 h, Nolo should weaken due to increasing southwesterly shear caused by the aforementioned upper low/trough. By 96-120 h, the GFS and ECMWF forecast Nolo to merge with the upper-level low, but do so in a way that leaves the tropical cyclone core more or less intact and allow the storm to maintain its intensity. This is supported by the regional hurricane models. Thus, the intensity forecast keeps the system as a hurricane at those times. Overall, the new intensity forecast is an update of the previous forecast. Now that Nolo is moving faster toward the west, the Tropical Storm Warning has been discontinued for Hawaii County, and the Tropical Storm Warning has been discontinued for Maui County. Key Messages: 1. Nolo is moving westward away from the Big Island of Hawaii, and the tropical cyclone watches and warnings for Hawaii have been discontinued. However, strong and gusty winds are expected for all of the Hawaiian Islands through the weekend, and interests in the Hawaiian Islands should continue to monitor the progress of Nolo. 2. Rain bands will continue through tonight across the Big Island and Maui, though the showers are expected to gradually diminish in intensity and frequency through Sunday. Additional areas of flooding and mudslides will be possible, especially in areas of steep terrain across the eastern and southern portions of the Big Island and eastern Maui. 3. Large and damaging waves are likely along portions of the Big Island's coastline through the weekend. FORECAST POSITIONS AND MAX WINDS INIT 27/0300Z 16.7N 156.5W 80 KT 90 MPH 12H 27/1200Z 16.6N 157.7W 90 KT 105 MPH 24H 28/0000Z 16.9N 159.6W 105 KT 120 MPH 36H 28/1200Z 17.7N 161.5W 115 KT 130 MPH 48H 29/0000Z 19.2N 162.8W 110 KT 125 MPH 60H 29/1200Z 20.8N 163.8W 95 KT 110 MPH 72H 30/0000Z 22.4N 164.5W 80 KT 90 MPH 96H 01/0000Z 23.1N 166.3W 65 KT 75 MPH 120H 02/0000Z 23.1N 169.3W 65 KT 75 MPH