January–February 2019 North American cold wave

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

January–February 2019 North American cold wave

In late January 2019, a severe cold wave struck parts of North America after a weakened polar vortex split into three lobes because of a sudden warming high in the atmosphere. One lobe moved south and lingered over central Canada and the north-central United States for about a week, bringing extreme cold, strong winds, and heavy snow.

Key facts
- When: Formed January 24, 2019 and dissipated in early March 2019.
- Where: Eastern Canada, Central and Eastern United States, Pacific Northwest, and Western Canada.
- Why: A sudden stratospheric warming weakened the jet stream and split the polar vortex, sending Arctic air southward.

Weather and temperatures
- The cold set many records across the region, with sub-zero temperatures and very strong wind chills.
- Cotton, Minnesota recorded a low of −56 °F (−49 °C) on January 30–31, one of the coldest readings in the area.
- Cities in the Midwest and Great Lakes, along with parts of Canada, saw some of their coldest days in years.
- February brought continued extreme cold to Western Canada and the Western United States, with record or near-record cold in several cities.

Impacts
- At least 22 people died in North America due to the cold.
- The cold caused widespread disruptions: about 2,700 US flights were canceled on January 30 and around 2,000 more on January 31; Amtrak also canceled trains.
- Many schools and businesses closed; the U.S. Postal Service paused mail delivery in parts of Michigan.
- In some places, the extreme cold even affected wildlife and infrastructure.

Regional notes
- Western Canada and the U.S. West experienced one of the coldest and snowiest periods on record for February.
- Vancouver recorded its coldest February on record; Seattle-area schools and services were disrupted by a significant, multi-day snowstorm in early February.
- In California, persistent cold and rain helped end a drought for the first time in years.
- Other notable effects included very cold conditions in Chicago, Detroit, Milwaukee, and parts of New York and New England.

March shift and aftermath
- By early March, the cold began to move east again, breaking some records in new areas.
- The late-season cold, combined with a deep Snowpack and continued wet conditions, helped trigger concerns about flooding in the Central United States as conditions later warmed.

Overall
- The 2018–19 winter featured a notable pattern of Arctic air pushing far southward in January and February, followed by a shift eastward in March. The period highlighted how jet-stream and polar-vortex dynamics can create extreme cold and heavy snowfall, with widespread human and economic impacts.