December 2021 absolutely obliterated the ERA5 record for number of days assigned to the "Arctic Low" (also known as "Pacific Ridge") North American weather regime: 29 days. The previous record holder was 24 days in 1984. 29 days is the average for all of DJFM! pic.twitter.com/FfzCk7BofA

— Dr Simon Lee (@SimonLeeWx) January 9, 2022