Polar Vortex and Extreamly Cold Temperatures

A wave of cold, artic air moved into the United States late in January 2019. Many record cold temperatures were broken. You can search on the news for that.

3-years of HRRR model analyses were used to compute empirical cumulative distributions of conditions for every hour of the year (Blaylock et al. 2018). This image show how much the temperatures at 0700 UTC on 31 January 2019 are less than the 5th percentile for the same time of year. This shows that temperatures are much more than 10 degrees colder than the 5th percentile temperature.