Examining the Minnesota statewide climate network back to the late 19th century reveals that December 1983 was the coldest ever.
It is the only December with a statewide average mean temperature that was below 0 degrees F — -0.8 degrees F to be precise. This represents a monthly mean value that is 15 degrees F less than the modern normal for December.
The persistent cold spell was amplified by a snowy month that produced snow depths around the state that ranged from 10 to 30 inches. Furthermore, the week leading up to Christmas Day (Dec. 18-24) was one of the coldest weeks in state history, with a mean statewide temperature of -17 degrees F, a value that is nearly 30 degrees F colder than normal.
Life on the farm that December was difficult, with challenges for keeping livestock fed and watered, coping with frozen water pumps, huge snowdrifts, and very large fuel bills for heating homes and other farm buildings.
Some of the records and climate statistics from December 1983 still stand today.
At midmonth, Dec. 11-15, winter storms brought persistent daily snowfalls, and in some cases blizzard conditions. Over the five days, some climate stations reported snowfall totals of 15 to 30 inches. Many outbreaks of arctic high pressure from very high latitudes brought record-setting cold temperatures. During the month, 483 new daily record-cold minimum temperatures were set within the statewide climate network, with more than 25 communities reporting at least one morning low temperature of -40 degrees F or colder.
Waseca HIGH Christmas Eve: -21 degrees F
At both Mora and Tower, the temperature dropped to -52 degrees F during the week before Christmas.
In addition, daytime brought little relief from the cold, as more than 500 new daily cold maximum temperature records were established in the statewide climate network as well.
On Dec. 24, the HIGH temperature for the day was a frigid -20 degrees F at Willmar, Morris and Rochester; and -21 degrees F at Waseca. Windchill readings (the combination of temperature and wind) were very dangerous and nearly off the charts, with values from the -60s F to -70s F.
Many communities reported temperatures that remained below 0 degrees F for up to 10 consecutive days. The climate was so harsh that there was relatively little travel during Christmas week, as most families chose to remain home.
With an El Niño episode in place this winter, it appears that Minnesota will experience a warmer-than-normal December, a pattern that is expected to persist into January as well.
Seeley is professor emeritus of climatology at the University of Minnesota.