Daily Archives: April 5, 2021

What is a red flag warning?

The National Weather Service issues, and cancels, fire weather watches (FWW), and red flag warnings (RFW) in coordination with the Wisconsin Department of Natural Resources and the U.S. Forest Service.

The weather service will not issue official warnings until certain threshold values, called red flag criteria, are forecast to occur. Red flag criteria differ from state to state. They usually include relative humidity values of 20% or less, winds of 20 mph or higher, and dry fuel conditions. Red Flag Warnings are usually only issued during the spring and fall fire weather seasons. Continue reading

Category: Meteorology, Severe Weather, Weather Dangers

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