National Weather Service United States Department of Commerce

Snow Squalls May Impact New Year's Eve Travel from the Great Lakes to the Mid-Atlantic; Heavy Rain & Isolated Severe Thunderstorms in Southern California

Snow squalls are likely to cross the Lower Great Lakes this evening and the Ohio Valley through the interior Northeast/northern Mid-Atlantic overnight, before potentially reaching the I-95 corridor from D.C. to New York City early New Year’s Day morning. Heavy rain and isolated severe thunderstorms will impact coastal southern California including Los Angeles tonight into early on New Year's Day. Read More >

Flood Return Period Calculator

Though this calculator is worded for the flood event return period it would work for any extreme weather event.

 

Enter the return period (ie..100 year flood)

Percent chance of occurrence

year flood %
Enter the number of years (ie..over the next 10 years)
There is a % chance that a year flood will occur over the next year(s)
year(s)