Tropical Cyclone Discussion
720 WTPA42 PHFO 262049 TCDCP2 Hurricane Nolo Discussion Number 25 NWS Central Pacific Hurricane Center Honolulu HI EP152026 Issued by NWS National Hurricane Center Miami FL 1100 AM HST Sat Sep 26 2026 Nolo still appears to be struggling with intrusions of dry mid-level air. After the Air Force Hurricane Hunters reported the eyewall was closed earlier this morning, recent vortex messages and radar images from South Point (PHWA) show the eyewall is once again open to the north. In addition, the minimum central pressure has risen slightly to 977 mb, and the peak 700-mb flight-level wind measured by the aircraft was 83 kt in the northwest quadrant. Based on these developments, the initial intensity is adjusted to 80 kt. Recent aircraft and radar fixes indicate the hurricane is now slowly moving just south of due west (260/4 kt). A faster westward motion away from the Big Island of Hawaii is expected during the next day or so as a mid-level ridge builds to the north of Hawaii. An upper-level trough currently to the northwest of the Hawaiian Islands is expected to amplify early next week, which should cause Nolo to turn toward the northwest and north-northwest on Monday and Tuesday. The models agree that Nolo will be clear of the main Hawaiian Islands by the time it makes this turn. On day 5, Nolo is forecast to resume a westward motion along the southern extent of a building ridge over the central Pacific. This track forecast is similar to but slightly faster than the previous prediction, generally falling between the latest TVCN and HCCA consensus aids. 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. If the hurricane can solidify a more resilient inner core, several skillful models (including Google DeepMind, HAFS-A/B, and HCCA) suggest that Nolo could intensify into a major hurricane on Sunday or Monday. An alternate scenario is that continued dry air intrusions cause Nolo to miss its window before increasingly southwesterly shear beyond 48 h induces a weakening trend. For now, the NHC intensity forecast continues to favor the stronger GDMI and HCCA solutions, which both have performed well for this event so far. Then, steady weakening is anticipated during the 60-120 h forecast period, generally following a blend of the HCCA and IVCN aids. Now that Nolo is moving away from the Big Island of Hawaii, the Hurricane Watch has been discontinued, but the Tropical Storm Warning remains in effect for Hawaii County. Key Messages: 1. Nolo has begun to move westward away from the Big Island of Hawaii, where tropical storm conditions are occurring and will continue into tonight, especially in areas of steep terrain. 2. Periods of heavy rain are expected to expand across the Big Island and eastern Maui through the weekend. Significant, life-threatening 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. 3. Large and damaging waves are likely along portions of the Big Island's coastline through the weekend. 4. A Tropical Storm Watch is in effect for Maui County, where tropical-storm-force gusts are occurring in areas of steep terrain. Strong and gusty winds are expected for all of the Hawaiian Islands through the weekend. FORECAST POSITIONS AND MAX WINDS INIT 26/2100Z 16.7N 156.0W 80 KT 90 MPH 12H 27/0600Z 16.7N 157.0W 90 KT 105 MPH 24H 27/1800Z 16.8N 158.8W 105 KT 120 MPH 36H 28/0600Z 17.2N 160.9W 115 KT 130 MPH 48H 28/1800Z 18.4N 162.5W 110 KT 125 MPH 60H 29/0600Z 20.2N 163.8W 95 KT 110 MPH 72H 29/1800Z 21.9N 164.5W 80 KT 90 MPH 96H 30/1800Z 23.2N 166.1W 65 KT 75 MPH 120H 01/1800Z 23.0N 168.8W 65 KT 75 MPH