Headline:
Flood Watch issued September 17 at 3:15AM HST until September 18 at 6:00AM HST by NWS Honolulu HI
Event:
Flood Watch
Urgency:
Future
Effective:
September 17, 2026 - 6:15am
Expires:
September 17, 2026 - 9:00pm
Description:
Remnant moisture from former Tropical Storm Norbert will bring
periods of moderate to heavy showers to mainly windward sides of the
Hawaiian Islands through late tonight.
* WHAT...Flash flooding caused by excessive rainfall continues to be
possible.
* WHERE...All main Hawaiian Islands.
* WHEN...Through late tonight.
* IMPACTS...Flood prone roads and other low lying areas may be closed
due to elevated runoff and overflowing streams. Urban areas may
receive more significant flooding and property damage due to rapid
runoff.
* ADDITIONAL DETAILS...
- A band of remnant moisture from Norbert will move west across the
islands through Friday, bringing moderate to locally heavy
showers to mainly windward sides of the islands. There is a
slight chance of thunderstorms as well, which could produce
briefly higher rain rates, increasing the risk of flash flooding.
Instruction:
You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.
Area Description:
Niihau; Kauai Southwest; Kauai Mountains; Waianae Coast; Oahu North Shore; Olomana; Central Oahu; Waianae Mountains; Lanai Mauka; Kahoolawe; Maui Windward West; Maui Leeward West; Haleakala Summit; Kona; Kohala; Big Island Interior; Big Island Summit; Kauai North; Kauai East; Kauai South; East Honolulu; Honolulu Metro; Ewa Plain; Koolau Windward; Koolau Leeward; Molokai Windward; Molokai Southeast; Molokai North; Molokai West; Molokai Leeward South; Lanai Windward; Lanai Leeward; Lanai South; Maui Central Valley North; Maui Central Valley South; Windward Haleakala; Kipahulu; South Maui/Upcountry; South Haleakala; Big Island South; Big Island Southeast; Big Island East; Big Island North
Forcast Office:
NWS Honolulu HI
Sender:
w-nws.webmaster@noaa.gov