If you are in a flood prone area move immediately to high ground. A flash flood is a sudden violent flood that can take from minutes to hours to develop. It is even possible to experience a flash flood in areas not immediately receiving rain. Flash Flood Warnings are changing to an Impact-Based format to improve public response. Read the factsheet.

The alerts web service displays NWS watches, warnings, advisories, and similar products. Click the main menu down-arrow for a quick guide and documentation.

Flash Flood Warnings are urgent messages as dangerous flooding can develop very rapidly, with a serious threat to life and/or property. Flash Flood Warnings are usually issued minutes to hours in advance of the onset of flooding.

With this change to impact-based FFWs, the NWS is aiming to improve the public response to Flash Flood Warnings by providing easily readable information and issuing WEA alerts only for flash flood events that require immediate life-saving action.

Flash Flood EMERGENCY issued for the EXCEEDINGLY RARE situations when extremely heavy rain is leading to a severe threat to human life and CATASTROPHIC DAMAGE from a flash flood is happening or will happen soon.

Flooding that begins within 6 hours, and often within 3 hours, of the heavy rainfall (or other cause). Flash Floods can be caused by a number of things, but is most often due to extremely heavy rainfall from thunderstorms.

A Flash Flood Warning is issued for flooding that normally occurs within six hours of heavy or intense rainfall. This results in small creeks and streams quickly rising out of their banks.

Flash flooding refers to a dangerous sudden rise in water in an urban area, in a canyon, or along a creek or wash over a normally dry land area. Flash floods result from heavy rainfall, sudden breaks in river ice jams, and dam or levee failures.

3 days ago · The following products are the most recent watches/warnings/advisories/statements that have been issued by the Weather Forecast Office in Honolulu, HI for the state of Hawaii, and the surrounding waters.

Be alert for the possibility of flash flooding anytime that rain fall is forecast. Be especially cautious from July to mid-September when severe thunderstorms can develop rapidly.