Over the weekend, the Storm Prediction Center (SPC) of the National Weather Service (NWS) issued two somewhat rare advisories: a "high" probability of severe weather in the convective outlook, and multiple Particularly Dangerous Situation (PDS) Tornado Watches.
It looks like these strong warnings were warranted, as shown in the overlay of storm reports on the 13Z convective outlook: http://www.spc.noaa.gov/products/outlook/archive/2017/day1otlk_v_20170122_1300.gif
Many lives were lost (17, I believe, at last count), but many more may have been lost without the level of urgency in the warnings, watches, and advisories issued.
-Michael McClellan (G, 12)