Flash Flood Warning Hawaii | Effective 03/21/2026 01:38

Headline: 
Flash Flood Warning issued March 20 at 10:38PM HST until March 21 at 2:00AM HST by NWS Honolulu HI
Event: 
Flash Flood Warning
Urgency: 
Immediate
Effective: 
March 21, 2026 - 1:38am
Expires: 
March 21, 2026 - 5:00am
Description: 
FFWHFO The National Weather Service in Honolulu has extended the * Flash Flood Warning for... The island of Oahu in Honolulu County * Until 200 AM HST. * At 1038 PM HST, emergency management reported numerous closed roads due to flooding. While the latest radar shows a significant decrease in shower coverage and intensity, return showers are expected into the early morning hours. The Wahiawa Reservoir remains elevated and will continue to be a concern due to additional heavy rain expected over the next few days. HAZARD...Flash flooding caused by heavy rain. SOURCE...Emergency management. IMPACT...Flooding in drainages, streams, rivers, roads, properties, and other low-lying areas. Public road closures possible in some areas. Landslides are possible in steep terrain. * Some locations that will experience flash flooding include... Wahiawa, Schofield Barracks, Wheeler Field, Haleiwa, Waialua, Mililani, Hauula, Laie, Waianae, Punaluu, Kahuku, Nanakuli, Waikane, Kaaawa, Helemano Housing, Whitmore Village, Waimea Valley, Waimea Bay, Mokuleia and Pupukea.
Instruction: 
Stay away from streams, rivers, drainage ditches, and culverts, even if they are currently dry. Do not cross fast flowing or rising water in your vehicle, or on foot. Turn around, don't drown. Be especially cautious at night when it is harder to recognize the dangers of flooding.
Area Description: 
Oahu in Honolulu, HI
Forcast Office: 
NWS Honolulu HI
Sender: 
w-nws.webmaster@noaa.gov