Flash Floods

Back-to-Back Pacific Storms to Impact the West Coast; Heavy Snow in the Central Appalachians

Back-to-back powerful Pacific storm systems to impact the Pacific Northwest and northern California through the end of this week with heavy rain, flooding, strong winds, and higher elevation mountain snow. A strong, long-duration atmospheric river will accompany the Pacific storms, bringing excessive rainfall and flash flooding to southwest Oregon and northwest California through the week. Read More >

Flash Flood Facts

Joseph City flash flood, July 1998. Flood waters damaged 44 homes.
(Photo: Navajo County)

Flash floods, which have been described as "more water than you want in less time than you have," are common in Northern Arizona. This is because the arid, sparsely vegetated environments found in this area have little capacity to absorb rainfall. The resulting runoff moves rapidly through the narrow canyons and steep terrain found throughout northern Arizona. In many areas, even small storms can turn normally dry washes and creeks into raging torrents of water in a matter of minutes.

Flash floods can occur at any time of year. 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.

A flash flood can travel miles beyond the storm that generated it, catching unwary hikers and motorists by surprise.

Flash Flood Watch

Issued to inform the public that conditions are favorable for flash flooding, but the timing and location of flooding is not certain or imminent.

During the Watch, residents should:

Exercise caution
Listen for NWS Flash Flood Warnings
Watch for signs of rising water
Be prepared to flee to higher ground on a moments notice

Flash Flood Warning

Issued when a flash flood is occurring or imminent.

When a Warning is issued:

Get out of the danger zone and move to higher ground immediately!
Don't waste time trying to save personal property
Do not cross rain-swollen streams!
Act quickly! Your margin of safety may be counted in seconds


Joseph City flash flood, July 1998 (Photo: Navajo County)	Joseph City flash flood, July 1998 (Photo: Navajo County)