The Storm Prediction Center puts out a "High Risk" of severe weather for the worst of severe weather outbreaks. Such outbreaks are relatively rare & confined to a set of conditions that produce the most intense, concentrated severe weather over a large area.
So what is the frequency of "High Risk" days in our viewing area?
Such solid, reliable archives for SPC Convective Outlook only go back to about 1990.
Convective SigMets (early daily convective outlook text) was established in 1978 with first PDS watch issued in 1982. The first Day 2 Convective Outlook occurred in 1986, along with the introduction of the Mesoscale Discussion, which precedes watch issuance.
The first second Day 1 outlook did not occur until 1995 with an evening outlook at 02z.
HIGH RISK DAYS PER DECADE IN OUR VIEWING AREA:
1990-1999: 3 (Despite the tornadoes in the area & the big tornado outbreak in the Southeast U.S. November 22, 1992, it was actually a forecasted MODERATE RISK, not HIGH).
HIGH RISK DAYS & WHAT TRANSIPIRED IN THE VIEWING AREA 1990-2019 are below.
In each of the High Risk days, significant severe weather outbreak occurred in the viewing area.
June 17, 1992
May 13, 1995
April 19, 1996
October 24, 2001
May 30, 2004
October 26, 2010
June 12, 2013
November 17, 2013