Nolo forecast to bring damaging winds, possible catastrophic flash flooding to Big Island

Updated at 5:50 p.m. Sept. 23, 2026.

Tropical Storm Nolo continues to slowly move northward toward the Big Island as of the 5 p.m. update from national and central pacific hurricane forecasters.

The Big Island also remains under a hurricane watch.

Nolo was located about 350 miles south of Hilo and about 295 miles south of South Point as of the latest update, still exhibiting sustained maximum winds of 45 mph with higher gusts. The storm had slowed down from earlier Wednesday afternoon and moving west-northwest at 6 mph.

It remains expected to make a turn to the west Friday night, passing south of the Big Island on Saturday.

Little change was noted as far as expected onset of conditions, with damaging tropical storm force winds reaching the Big Island as early as Friday morning and dangerous hurricane force winds possible by Friday night.

Bands of intense showers and thunderstorms associated with Nolo will reach the Big Island as early as Thursday. Excessive rainfall is possible, which could lead to locally catastrophic flash flooding, landslides and mudslides.

Flooding can occur even in areas not usually prone to flooding.

Storm total rainfall amounts greater than 20 inches are possible on the Big Island, with localized amounts of 35 inches.

Swell generated by Nolo could bring very large and rough surf as well as dangerous rip currents for south- and southeast-facing shores.

Tornadoes and large waterspouts also will be possible, mainly over and near the Big Island along and to the right of the hurricane track.

Potential impacts

• FLOODING RAIN: Prepare for life-threatening rainfall and flooding having possible devastating impacts around the Big Island. Potential impacts include:
  • Extreme flooding could prompt numerous evacuations and rescues.
  • Rivers and tributaries could overwhelmingly overflow their banks in many places with deep moving water.
  • Small streams, creeks, canals, arroyos and ditches might become raging rivers. In mountain areas, deadly runoff could rage down valleys while increasing susceptibility to rockslides and mudslides.
  • Flood control systems and barriers could become stressed.
  • Flood waters can enter numerous structures within multiple communities, some structures becoming uninhabitable or washed away.
  • Numerous places where flood waters might cover escape routes.
  • Streets and parking lots become rivers of raging water with underpasses submerged.
  • Driving conditions become very dangerous.
  • Numerous road and bridge closures with some weakened or washed out.

• WIND: Prepare for life-threatening wind having possible extensive impacts around the Big Island. Potential impacts include:
  • Considerable roof damage to sturdy buildings, with some having window, door and garage door failures leading to structural damage.
  • Mobile homes severely damaged, with some destroyed.
  • Damage accentuated by airborne projectiles.
  • Locations could be uninhabitable for weeks.
  • Many large trees snapped or uprooted along with fences and roadway signs blown over.
  • Some roads impassable from large debris and more within urban or heavily wooded places.
  • Several bridges, causeways and access routes impassable.
  • Large areas with power and communications outages.

• SURGE: Prepare for locally hazardous surge having possible limited impacts around the Big Island. Potential impacts include:
  • Localized inundation with storm surge flooding mainly along immediate shorelines and in low-lying spots or in areas farther inland near where higher surge waters move ashore.
  • Sections of near-shore roads and parking lots become overspread with surge water.
  • Driving conditions dangerous in places where surge water covers the road.
  • Moderate beach erosion. Heavy surf also breaching dunes, mainly in usually vulnerable locations.
  • Strong rip currents.
  • Minor to locally moderate damage to marinas, docks, boardwalks, and piers.
  • A few small craft broken away from moorings.

• TORNADOES: Prepare for a tornado event having possible limited impacts around
  the Big Island. Potential impacts include:
  • The occurrence of isolated tornadoes can hinder execution of emergency plans during tropical events.
  • A few places could experience tornado damage, along with power and communications disruptions.
  • Locations could realize roofs peeled off buildings, chimneys toppled, mobile homes pushed off foundations or overturned, large tree tops and branches snapped off, shallow-rooted trees knocked over, moving vehicles blown off roads and small boats pulled from moorings.

Precautionary/preparedness actions

• EVACUATIONS: Follow the advice of local officials.
• OTHER PREPAREDNESS INFORMATION: Now is the time to check your emergency plan and emergency supplies kit to take necessary actions to protect your family and secure your home or business.
• VISITORS: Know the name of the county or parish in which you are located and where it is relative to current watches and warnings. If staying at a hotel, ask the management staff about their onsite disaster plan. Listen for evacuation orders, especially pertaining to area visitors.

“When making safety and preparedness decisions, do not focus on the exact forecast track since hazards such as flooding rain, damaging wind gusts, storm surge and tornadoes extend well away from the center of the storm,” National Weather Service forecasters said.

If you are in a place vulnerable to high wind — such as near large trees, a manufactured home, upper floors of a high-rise building or on a boat — plan to move to safe shelter.

If you live in a place particularly vulnerable to flooding — such as near the ocean or a large inland lake, in a low-lying or poor drainage area, in a valley or near an already swollen river — plan to move to safe shelter on higher ground.

“Always heed the advice of local officials and comply with orders that are issued,” forecasters said. “Do not needlessly jeopardize your life or the lives of others.”

When securing your property, outside preparations should be concluded as soon as possible before conditions deteriorate. The onset of strong gusty winds or flooding can cause certain preparedness activities to become unsafe.

Be sure to let friends and family members know of your intentions for weathering the storm and your whereabouts. Have someone located away from the threatened area serve as your point of contact. Share vital contact information with othersk, and eep cellphones handy and charged.

Check on those who might not be fully aware of the situation or unable to make personal preparations.

The public is advised to closely monitor the National Weather Service Honolulu forecast office website, National Oceanic and Atmospheric Administration Weather Radio and local news outlets for official storm information and listen for possible changes to the forecast.

There is a threat from tornadoes with this storm, so also be sure to have multiple ways to receive tornado warnings and be ready to shelter quickly.

Additional sources of information

• Disaster preparedness information: American Red Cross.
• Appropriate preparations: Ready.gov.

For storm information specific to your area, including possible inland watches and warnings, monitor products issued by the National Weather Service Honolulu forecast office.