Pulled from the other thread, but I count 7 of those 25 periods from 2012-present. It's almost like the atmosphere is still on a post-4/27/11 hangover, because it hasn't produced a proper tornado season since then. There's a day here, a day or 2 there with long stretches of particularly hostile patterns locked in between (massive central CONUS ride, or cold eastern CONUS trough). The bigger events have been largely mesoscale-driven, with something going awry with almost all the potential big synoptically evident outbreaks (with the exception of 2012 which was basically March 2 and April 14, and April 28 in 2014). The only consistently active period in that stretch was the back half of May 2013 including of course Moore, Rozel and El Reno, and that was very central OK/KS from I-70 south centric with little activity in other parts of the Plains/Midwest.
Got to wonder when is the next season with a 7-14 day period of activity with multiple MDT to HIGH risk caliber events (that perform) spread across varying regions of the Plains/Midwest like May 4-10, 2003, May 22-30, 2004, or pretty much all of May through June 12, 2008.
Not sure I like the sound of your post Fred as it would seem to imply a reduced severe threat for the upper Midwest this spring as systems get crushed by cold air slamming in from the north/west instead of further deepening as they lift out of the Rockies.
I realize every decade has its active years and its quieter years, but this second decade of the 21st century seems different than any in the record when it comes to severe weather activity, at least after 2010. 2011 had its uber-hyperactive April centered from the MS river eastward, followed by a May "season" that was basically three days, two of which featured extremely violent events.
Every year since then has been what I would call "inactive with a couple active days here and there" or "with stretches that looked like they might be active but had wrenches thrown in" (thinking particularly of that stretch in May 2015 culminating in May 16, which *could* have been one of the biggest west-of-I-35 Plains events since the 1990s).