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Vigorous System Impacting the Northwest; Large System To Affect East

A potent storm system is delivering heavy rainfall, strong winds, rough surf and beach erosion along the Pacific Northwest coast with mountain snow inland. Expect a couple more systems to arrive late week into the weekend. Meanwhile, another developing large scale system will deliver a heavy rain and renewed flood threat to much of the East late Wednesday through Friday, which may impact travel. Read More >

Flash Flood Guidance

 

Flash Flood Guidance is an estimate of the amount of rainfall required over a given area during a given duration to cause small streams to flood. These estimates are based on the current soil moisture and stream flow conditions for the area. Flash Flood Guidance is routinely issued by National Weather Service (NWS) River Forecast Centers, and is used by NWS Weather Forecast Offices when issuing Flash Flood Watches and Warnings to the public. Note: Less rainfall is required to produce flash flooding in urban areas.

 

 


 


 

One-Hour Flash Flood Guidance


 

Latest 1-hour Flash Flood Guidance Graphic.

 

 

Three-Hour Flash Flood Guidance


 

Latest 3-hour Flash Flood Guidance Graphic.

 

 

Six-Hour Flash Flood Guidance


 

Latest 6-hour Flash Flood Guidance Graphic.

 

 


Flash Flood Guidance Text Products

 

Southern New England

Maine & New Hampshire

New York & Vermont

Headwater Guidance