One of the scariest severe weather scenarios is a nighttime tornado hitting a densely populated community during the cold months when folks aren’t expecting such rough weather. That very situation played out this past Tuesday as a line of severe thunderstorms swept across northern Texas. The incident is a stark reminder that severe thunderstorms and tornadoes aren’t confined to the warm season, and severe storms are a hazard during the cold months as well.
The tornado that hit Arlington, Texas, last week caused EF-2 damage as it passed just south of the heart of the city. The tornado touched down as part of a larger bout of severe thunderstorms that swept across the southern Plains before Thanksgiving.
Severe weather remains an ever-present threat even as the weather gets colder and we relax into a holiday mindset.
While the frequency and coverage of severe storms during the fall and winter months pale in comparison to what’s possible in the spring, it’s still a threat we need to take seriously.
In fact, the processes that drive spring and winter severe weather outbreaks are similar in origin. The jet stream sags south over the United States as colder temperatures migrate southward. These sags in the jet stream allow vast low-pressure systems to sweep across the country, producing active weather from border to border.
While these storms are best known for heavy snow in northern states, the southern side of these winter storms can drag warm and humid air north from the Gulf of Mexico. The combination of strong upper-level winds, a potent cold front at the surface, and unstable air provide the perfect environment for strong thunderstorms to develop.
Late season severe thunderstorms are no joke—especially the risk for tornadoes. A strong EF-2 tornado cut through the heart of Mobile, Alabama, on Christmas Day in 2012. An F4 tornado tore across eastern North Carolina in late November 1988, killing several people as it wound along a path more than 80 miles long.
A history of tornadoes during the month of December between 1950 and 2018 reveals a pattern that favors the southeastern United States. The threat tends to focus on the Lower Mississippi Valley as winter storms ramp up over the Plains and move east toward the Midwest.
Tornadoes are always dangerous, of course, but tornadoes that form in the winter require a little extra caution.
The first threat we typically don’t deal with in the spring is that it gets dark much earlier in the day this time of year. Many folks—whether we like it or not—still like to peek outside to see if they can see a tornado before they’ll dive for cover. It’s a terrible habit that we need to break, but it’s especially worrisome in the winter when it’s often too dark to see tornadoes coming until it’s too late.
The second threat is that we’re not accustomed to watching out for severe weather warnings when it’s this late in the year. It’s easy to tune out the weather when you’re expecting a chill rather than a dangerous thunderstorm. Listening for severe weather forecasts and urgent warnings from the National Weather Service should be a year-round habit rather than just something to worry about in the warmer months.
The best practice to protect against severe weather is to make sure you have multiple ways to receive warnings the moment they’re issued. Take a moment to check that emergency alerts are enabled on your smartphone. Lots of folks disable these push alerts when they go off at an inconvenient time. That’s a big mistake. These alerts, which sound the moment a tornado warning is issued for your location, have been credited with saving countless lives.
Even though they’re a bit outdated given today’s advanced technology, a trusty NOAA Weather Radio is still a fantastic investment. These devices can be programmed to chirp like a smoke detector when a severe weather watch or warning is issued for your county. Reliable weather apps, local television stations, and radio stations are also fantastic resources to receive urgent weather alerts in a timely manner.