My Blog on this:
Yearly summary 2017 Mean temperature 49.0 (+1.1) above normal. High (108), Low (-20). Peak wind gust (49 mph), Precipitation 20.37 (+.35) This was the coolest year in last 3, or since beginning of this stations data.
Contrarily airport mean temperature was (50.5) 5th warmest ever. Airport was within a few tenths every year prior until now (+1.5) above this station and surrounding stations continuing into 2018. Changeover +1.7 was recorded and observed by MADIS in March which was same time I noticed the sudden rise. MADIS is meteorological observational database and data delivery system which tracks all data.
The irony of it all, its now confirmed right here in Nebraska "Man Made Warming" is real by just turning the thermometers up and bingo you have it. To my surprise while researching it was pointed out by another weather enthusiast, these Airport ASOS stations everyone thought so accurate including myself actually have loose tolerances on thermometer (+/- 2F) so weather records can get smashed by just having poorly calibrated instrument.