textproduct: Honolulu

SYNOPSIS

Hurricane Nolo continues to slowly move to the north towards the Big Island, and is expected to make a turn to the west tonight. Moisture on the north side of Nolo will interact with the terrain of the Big Island and Maui, and could lead to significant flash flooding, particularly on the windward and southeast portions of the Big Island. Localized strong and gust winds are possible statewide, with the highest winds expected on the Big Island due to the proximity to Nolo.

SHORT TERM UPDATE

Hurricane Nolo continues moving slowly towards the north-northeast about 5 mph. It was located around 175 miles south of South Point late this morning. Rainbands associated with Nolo's circulation are slowly moving north and should start affecting the Big Island later tonight. Rain intensity will remain sensitive to just how far north Nolo progresses before making its westward turn which is the sticking point in the forecast in terms of uncertainty.

For this afternoon and into the evening hours, winds will continue to gradually increase statewide. A wind advisory has been issued for Niihau, Kauai and Oahu and will be in effect from Saturday morning through Sunday evening. Weather will begin to deteriorate at a faster pace as hurricane Nolo approaches from the south tonight. Intermittent periods of moderate to heavy rainfall will spread first across Big Island later today and Saturday over Maui.

The next update from NHC is scheduled for 5pm HST.

Otherwise in the short term, chances for rainfall were increase for the western islands for the daylight hours based on latest radar and satellite data.

PREV DISCUSSION

Issued at 522 AM HST Fri Sep 25 2026 The main change this morning to the forecast was to lower the additional rainfall that could fall over Maui County and the Big Island, and to modify the winds in keeping with the latest forecast track and intensity of Hurricane Nolo.

Hurricane Nola continues to moving slowly northward towards the Big Island early this morning. An upper level trough west of the islands is helping to steer Nolo. As the trough moves to the west tonight and Saturday, Nolo should begin to make its turn westward. Then a building ridge north of the state will help Nolo to continue to move to the west. The current forecast track is similar to yesterday evenings forecast, however with a delay in the onset of rain on the Big Island and Maui, and in keeping with other model guidance, have lowered the additional rainfall that is expected for those areas. While we have lowered some of the threat, the possibility of flooding continues. And with many areas of the southeast portion of the Big Island susceptible due the recent rains, any additional rainfall could cause significant issues. As such, the Flood Watch continues for Maui and the Big Island. Additionally, some modifications to the winds, primarily to lower them over the next couple of days, have been made, also keeping with the latest model guidance.

With regards to the winds over Kauai County and Oahu, have opted to hold off on any wind headlines this morning. The west turn timing plays a big factor in many parts of the forecast, including the timing of winds for Kauai County and Oahu. Oahu remains at a slightly higher chance for meeting High Wind Warning criteria, but still a good shot for Kauai reaching advisory levels.

Satellite derived precipitable water (PW) shows the deeper moisture has moved over the Big Island, but radar shows that the shower activity remains to the south. Still expecting shower activity to increase over the Big Island today as Nolo moves north, pushing that moisture area into the Big Island. The additional rainfall totals were trended down with the morning package, however the possibility of localized significant totals remains. Strengthening northeast winds are expected to drive moderate to heavy showers over windward portions of the Big Island and Maui as moisture deepens and spreads northward over the region.

A High Wind Watch for Oahu Saturday and Saturday night remains a possibility. The Hurricane Watch and Tropical Storm Warning remain in effect for the Big Island and the Tropical Storm Watch continues for Maui County.

By the middle of next week, troughing will draw Nolo sharply north or northeastward west of Kauai. The end of next week will then feature light south to southeast flow as Nolo lifts north of the area and gradient over the state weakens substantially.

AVIATION

Gusty trade winds continue across most of the islands today with gusts peaking between 25 to 35 knots while gusts up to 40 knots are possible at the windiest sites. Winds are expected to remain gusty through the end of the TAF period. Confidence has decreased slightly in showers reaching the more northern islands given Nolo's more southerly track. That being said, trade showers are likely to continue across windward and mauka areas of the western islands today while heavier rain remains concentrated from Molokai down through the Big Island. The highest potential for moderate to heavy rain remains across the Big Island with reductions in ceilings and visibilities likely as shower activity becomes more frequent. This may result in periods of IFR to LIFR conditions in heavier showers on the Big Island today into tomorrow. Thunderstorm chances remain low for the Big Island. Temporary MVFR conditions are possible across the rest of the islands as showers develop.

AIRMET Sierra is in effect for mountain obscuration for windward areas of all islands today.

AIRMET Tango remains in effect for moderate turbulence downwind of island terrain due to breezy trade winds. Expect this to continue through the forecast period. It is possible that an AIRMET for sustained 30 kt winds will be needed for the Big Island by Saturday as Nolo passes to the south.

TC SIGMET Oscar series covers Hurricane Nolo, and interests should continue to monitor for updates to this SIGMET.

MARINE

Hurricane Warnings around the Big Island and Tropical Storm Warnings around Maui County remain in effect as Hurricane Nolo inches northward. It is still forecast to turn west well before reaching the Big Island or adjacent nearshore waters, but strong winds and high seas can nonetheless be expected. South to southeast fresh swell emanating from Nolo will spread west across the southern nearshore waters as the system tracks west through early next week. The High Surf Advisory (HSA) for E and SE facing shores of the Big Island, Maui, and Molokai remains in effect and has been extended through Sunday. In addition, an HSA is now in effect for Kauai, Oahu, and Niihau beginning tonight due to strengthening trades. A small, long period NW swell fills in this weekend in maintenance of elevated surf along exposed shorelines into early next week.

FIRE WEATHER

Issued at 522 AM HST Fri Sep 25 2026 Issued at 458 AM HST Fri Sep 25 2026

Winds will steadily as Hurricane Nolo moves closer. Very strong winds are possible on the Big Island, though heavy rainfall will likely mitigate fire danger over most areas. From Kauai to Maui County, rainfall over the last month has led to some improvement in fuels, but the gusty trade winds will produce moderate fire weather conditions over drier leeward areas through the weekend.

HFO WATCHES/WARNINGS/ADVISORIES

Wind Advisory from 6 AM Saturday to 6 PM HST Sunday for Central Oahu-East Honolulu-Ewa Plain-Honolulu Metro-Kauai East-Kauai Mountains-Kauai North-Kauai South-Kauai Southwest-Koolau Leeward- Koolau Windward-Niihau-Oahu North Shore-Olomana-Waianae Coast- Waianae Mountains.

High Surf Advisory from 6 PM this evening to 6 PM HST Sunday for Kauai East-Kauai South-Koolau Windward-Olomana.

Flood Watch through Saturday afternoon for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Haleakala Summit-Kahoolawe-Kipahulu- Kohala-Kona-Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward- Maui Central Valley North-Maui Central Valley South-Maui Leeward West-Maui Windward West-Molokai Leeward South-Molokai North- Molokai Southeast-Molokai West-Molokai Windward-South Haleakala- South Maui/Upcountry-Windward Haleakala.

Tropical Storm Watch for Haleakala Summit-Kahoolawe-Kipahulu- Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward-Maui Central Valley North-Maui Central Valley South-Maui Leeward West- Maui Windward West-Molokai Leeward South-Molokai North-Molokai Southeast-Molokai West-Molokai Windward-South Haleakala-South Maui/Upcountry-Windward Haleakala.

High Surf Advisory until 6 PM HST Sunday for Big Island East-Big Island North-Big Island Southeast-Kipahulu-Maui Windward West- Molokai Southeast-Molokai Windward-South Haleakala-Windward Haleakala.

Hurricane Watch for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Kohala-Kona.

Tropical Storm Warning for Big Island East-Big Island Interior- Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Kohala-Kona.

Tropical Storm Watch for Kaiwi Channel-Maalaea Bay-Maui County Leeward Waters-Maui County Windward Waters-Pailolo Channel.

Hurricane Watch for Alenuihaha Channel-Big Island Leeward Waters- Big Island Southeast Waters-Big Island Windward Waters.

Tropical Storm Warning for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters-Big Island Windward Waters.

Small Craft Advisory until 6 PM HST Saturday for Kauai Channel- Kauai Leeward Waters-Kauai Northwest Waters-Kauai Windward Waters-Oahu Leeward Waters-Oahu Windward Waters.