The National Oceanic and Atmospheric Administration (NOAA) says that above average temps spread across most of the contiguous United States during January. This was accompanied by below-average precip for much of the country and resulted in an atypical lack of snow for much of the Northern Plains, Midwest and Northeast. The result was an average contiguous U.S. temp for January of 36.3° F, which makes it the fourth warmest January on record and the warmest since 2006.
On a state-by-state basis, NOAA reports nine states (Arizona, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, South Dakota and Wyoming) had temps ranking among their 10 warmest while only Florida and Washington had temps near average. No state was cooler than average according to NOAA. Many locations across the Northern Plains set all-time record highs for January.
On the precipitation front, NOAA explains that the Southern Plains and Great Lakes regions were wetter than average for January, making that the second consecutive month Texas has received above-average precip.
On the other hand, the Central Plains received below-average precipitation, with Kansas having its third driest January on record, according to NOAA.
The Northern Plains, Midwest and Northeast also saw below average snowfall for January due to the especially warm and dry conditions. NOAA elaborates, "According to data from the Rutgers Global Snow Lab, the average snow extent during January was 1.0 million square miles, which was 329,000 square miles below the 1981-2010 average. This marks the third smallest January snow cover extent in the 46-year period of record."