A high risk severe weather event is the greatest threat level issued by the Storm Prediction Center (SPC) for convective weather events in the United States. On the scale from one to five, a high risk is a level five; thus, high risks are issued only when forecasters at the SPC are confident of a major severe weather outbreak. This is usually for major tornado outbreaks with numerous strong to violent tornadoes expected, and occasionally derechos with widespread destructive wind gusts, and these outlooks are typically reserved for the most extreme events. They are generally only issued on the day of the event. However, there have been two occurrences (April 7, 2006, and April 14, 2012) of a high risk being issued for Day 2 of the outlook period (with the event occurring the following day). Under the official protocol, a high risk cannot be issued for Day 3 of the outlook period.
Thirty-four high risks were issued in the 1980s.
Sixty high risks were issued in the 1990s.
There were no high risk days in 2000.
There were no high risk days in 2015, 2016, or 2018.
There were no high-risk days in 2020 or 2022.
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