Flash Flood Warning Issued for Oahu as Heavy Rain Impacts Honolulu County

Alert Details

The National Weather Service in Honolulu has issued a Flash Flood Warning for the island of Oahu in Honolulu County. This alert was issued at 3:35 AM HST on February 21, 2026, after radar and automated rain gauges indicated significant rainfall across the region.

Affected Areas

The warning covers the entire island of Oahu. Specific locations that will experience flash flooding include:

• Honolulu, Moanalua, Salt Lake, and Kalihi
• Pearl City, Aiea, Halawa, and Waipahu
• Mililani, Wahiawa, Waikele, Waipio, and Wheeler Field
• Kaneohe, Kahaluu, Ahuimanu, and Kaaawa
• Waiahole, Waikane, Punaluu, and other areas near the Koolau Mountains

What You Should Do

Residents and travelers are urged to stay away from streams, rivers, drainage ditches, and culverts, even if they are currently dry. Do not attempt to cross flooded roads, as public road closures are possible in some areas. Additionally, those in areas with steep terrain should remain vigilant as landslides are possible.

Expected Conditions

According to the NWS, radar and automated gauges show heavy rain falling over the Koolau Mountains, impacting both central and eastern sections of Oahu. Rain is falling at a rate of 2 to 3 inches per hour. Stream levels are rising rapidly, and flash flooding is either ongoing or expected to begin shortly. Hazards include flooding in drainages, streams, rivers, roads, properties, and other low-lying areas.

Timeline

The Flash Flood Warning is effective immediately and is currently set to expire at 6:45 AM HST on Saturday, February 21, 2026.