Another Arctic Outbreak, March 2-4, 2019

An Arctic air mass surged into Minnesota March 2nd through 4th, breaking numerous cold weather records across the state, and creating some of the coldest daytime conditions ever recorded during March.

The meteorological set-up mimicked that of the extreme cold event of late January 2019, with the main difference being the time of year. This time around, the originating air mass in northern Canada was somewhat warmer, thanks to intensifying sunlight in the high latitudes of North America. This warmer starting condition created smaller temperature differences between the cold air mass and the air mass ahead of it, and these lesser differences then led to somewhat less intense winds. Although this cold outbreak was "warmer" the one in January, it was roughly as extreme in terms of departure from normal.

Temperatures early on March 3rd fell into the -10s and -20s across the state, with wind chills in the -30s and -40s. These conditions led to daily overnight low temperature records being set or tied at Canby, Caledonia, and the Twin Cities, along with a handful of other stations. The winds kept the air mixing, and prevented even lower temperatures from being recorded.

Those same winds had the opposite effect during the day, and kept temperature unusually low for early March. Dozens of stations throughout Minnesota shattered their daily record for the lowest high temperature ever observed on March 3rd  and high temperatures generally were among the five or ten lowest ever recorded during the month. St. Cloud, along with 18 other long-term stations, observed their lowest March high temperature on record.

Quick facts about the March 2-4, 2019 cold outbreak:

• Number of daily record lows on March 3rd at sites with over 30 years of station history: 24
• Number of daily record low highs on March 3rd at sites with over 30 years of station history: 18
• Number of daily record lows on March 4th at sites with over 30 years of station history: 26
• Number of daily record low highs on March 4th at sites with over 30 years of station history: 48
• Lowest temperature recorded during outbreak: -35F, at Cotton
• Lowest high temperature recorded: -7F, at Warren
• Number of all-time lows for any day in March recorded: 2
• Number of all-time low highs for any day in March recorded: 19