STORM2K

Moderate Risk of Severe Storms suddenly issued for parts of the High Plains. Large hail is the biggest threat, but some tornadoes are possible.

I wouldn't say "out of nowhere." In my opinion, after looking at all the soundings in that part of the country, I would have issued a mdt risk area myself. It was mostly a wind threat than anything, but still a svr tstm.

Tornado Reports - 5
Wind Reports - 95/11
Hail Reports - 66/7

Seems like the MDT was justified...