CoreLogic tracks the nationwide winter storm that brought blizzard conditions and severe thunderstorms
- A winter storm brought blizzard conditions to the Northern Plains/Upper Midwest and tornadoes to the southern U.S. The storm is still evolving, bringing winter storm warnings and watches in the Northeast, as well as tornado watches in Florida.
- As of today, more than six inches of snow fell across the Northern Plains from Utah to Minneapolis, Minnesota, with some areas receiving up to two feet over a 72-hour period (from Dec. 11-14). Blizzard conditions (winds blowing at least 35 mph, visibility reduced to a quarter of a mile or less) accompanied the snow across North Dakota, South Dakota, Colorado and Nebraska, according to the National Weather Service (NWS). Traffic was disrupted on several interstates in Nebraska when the roads closed due to the blizzard conditions.
- More than 50 tornadoes spawned from Texas to Florida starting Dec. 13. The NWS reported over 64 tornadoes (Figure 1), and the governmental agency confirmed that several of the reported tornadoes were EF-1 strength or greater. A few EF-2 tornadoes, with windspeeds upwards of 130 mph, were confirmed in Texas, Louisiana and Mississippi. An EF-3 tornado was confirmed near Lake D’Arbonne in north-central Louisiana.
- The most intense confirmed tornadoes occurred in sparsely-populated areas. However, an EF-0 tornado was confirmed in the northwestern Dallas-Fort Worth metro area on Dec. 13 (Figure 2, left) and two EF-U (unconfirmed intensity) tornadoes were confirmed in the New Orleans metro area near the towns of Montz and Gretna, Louisiana (Figure 2, right).
- The full extent of the damage in Texas and New Orleans is still unknown, but initial reports indicate material damage to homes and businesses. Damage to the roofs and siding of residential properties were reported across the impacted regions. Commercial properties such as a Sam’s Club in Grapevine, Texas, and a hospital in New Iberia, Louisiana, were damaged as well. The New Iberia Medical Center remains operational despite the damage.
- This week’s New Orleans tornado crossed a portion of the same path taken by the EF-3 tornado on March 22, 2022. For instance, a brewery in the suburban town of Arabi, Louisiana, that was finishing up damage repairs from the March 22 tornado was destroyed again by this tornado.
A History of Off-Season Tornadoes Outside the “Alley”
- The official tornado season extends from March through July, according to The National Oceanic and Atmospheric Administration (NOAA). However, tornadic activity outside of the official season is not uncommon. Additionally, storms are not confined to “Tornado Alley,” the area referring to the highest-activity region of the U.S., which extends from northern Texas to South Dakota. Tornado risk extends outside of the “alley, ” especially during the winter months when the region of highest activity shifts southeast, including the areas hit by the tornadoes this week.
- As recently as November 2022, tornadoes damaged properties in Louisiana and Mississippi. In a two-day period in March 2022, more than 20 tornadoes affected the same regions of Texas and New Orleans that were hit this week. In December 2021, a severe storm outbreak that included several tornadoes impacted over 500,000 homes with a total reconstruction value of over $125 billion. CoreLogic estimated that the total property damage from this December 2021 tornado outbreak exceeded $4.46 billion.
This situation in the Southeast is still unfolding. Severe thunderstorm watches and warnings are in place across central Florida, and damage survey crews are investigating the full extent of the destruction from Texas to Louisiana.
