Update at 3:42 p.m. Oct. 28, 2026: A flood watch previously in effect through early Thursday morning was canceled by National Weather Service forecasters at the Honolulu forecast office.
Story originally published 5:42 p.m. Oct. 27, 2026: National Weather Service forecasters in Honolulu advise the public that a flood watch is in effect through late Wednesday night for the entire state and early Thursday morning for Kaua‘i because of the expected possibility of flash flooding caused by excessive rainfall associated with a trough moving over the islands from west to east.
Heavy showers and isolated thunderstorms with intense rainfall rates can develop at any time through Wednesday night, with the greatest flood threat focused over O‘ahu and Maui County.
However, all islands are at risk.
Significant flooding is possible because of overflow from streams and drainages. Roads in several areas could be closed, along with property damage in urban or low-lying spots because of runoff.
Landslides also could occur in areas with steep terrain.
The incoming trough is forecast to bring abundant tropical moisture through at least Wednesday night.
Forecasters advise the public to monitor later forecasts for their areas and be prepared to take action if flash flood warnings are issued.
