Maximum Statewide Temperature Range

There have been several references in social media the last few days  (here and here) regarding the range of temperatures across the state approaching 100 degrees. I thought it would be interesting to see what the greatest daily temperature range was in the Alaska climate record. The winner appears to be February 3rd, 1977, with a statewide temperature range of 125°F. The high temperature was +60°F at Annette Island and the low temperature was -65°F at Umiat. There are 5 or 6 days in the GHCN database with larger ranges but they all contain highly questionable values; e.g., a max high of +73°F with the second highest of +45°F. None of those instances were even marginal so they were easy to toss out. No more than 4 days have ever had a daily range of over 120°F.

I initially expected the record range day to fall in mid February to early March since the far northerly latitudes receive little insolation and the stations in Southeast Alaska receive a fair amount. What surprised me was that December and January are the months most likely to see a day with a statewide diurnal range in excess on 110°F.