February 15–20, 2021 North American winter storm

From February 15–20, 2021, a significant and widespread winter storm, also unofficially referred to as Winter Storm Viola by the Weather Channel, or to some as simply The North Texas Freeze, caused major impacts and additional damage across much of the United States, Northern Mexico, and Southern Canada, and worsening conditions already significantly hampered by another destructive winter storm several days prior. The system started out as a winter storm on the West Coast of the United States on February 15, later moving southeast into the Southern Plains and Deep South from February 16–17. It then moved into the Appalachian Mountains and Northeastern United States, before finally moving out to sea on February 20. The storm subsequently became a powerful low pressure system over the North Atlantic, before eventually dissipating on February 26.

The system resulted in over 170 million people being placed under winter weather alerts, stretching from the West Coast to the East Coast. Over 4 million people lost power due to the storm, particularly in areas of the Deep South and interior Southeast. The system worsened the 2021 Texas power crisis, causing additional major damage to the Texas power grid just days after the previous storm came through the area and hampering recovery efforts. It also contributed to a historic cold wave that affected most of the Central United States. In total, the winter storm resulted in at least 29 fatalities, with 23 in the United States and six in Mexico. The system is estimated to have caused at least $2 billion (2021 USD) in damages, mainly due to blackouts and structural damage.