Preparedness In A New Tornado Alley

A tornado forming above a rural landscape under dark stormy skies.

May 22, 2021 | Karolinn Fiscaletti

Climate change is affecting the usual trend of storms in Colorado

While some of the United States is experiencing light April showers, it’s time for Coloradans to prepare for much more severe forms of weather. Drought, hail, thunderstorms, and flooding may be on most Coloradans’ minds this year, but with the unique risks they may pose to your property and even your life, it’s also important to factor tornadoes into your weather preparedness checklist. Read on to learn more about which areas of the state are at the greatest risk, what meteorologists are predicting for the 2021 season, and what resources are available to help you stay safe.

Fast Facts

People who are less familiar with tornadoes may imagine them in their deadliest forms – those often depicted in television or film. In reality, 77% of tornadoes in the United States are considered weak, measuring between EF-0 and EF-1 on the Enhanced Fujita Tornado Damage Intensity Scale, bringing winds no greater than 110 mph (measured in 3-second gusts). Meanwhile, 95% of tornadoes never exceed an EF-3 rating, with winds reaching a maximum of 165 mph. Still, like other forms of severe weather, tornadoes are unpredictable. There’s no way to precisely determine a tornado’s intensity before it touches down, and no way to know for certain whether a supercell will develop. Plus, even relatively weak tornadoes have the potential to cause property damage and endanger lives.

Statistics for Colorado

Although tornadoes have been reported in Colorado nine months out of the year, most occur between May and August, with two-thirds of all activity recorded in May and June. That said, not all tornadoes are equal. Most of Colorado’s are relatively weak, with wind speeds less than 100 mph. However, more severe events do happen. Come spring, the areas that see the most activity are the Front Range and foothill counties, east of the Continental Divide.

These eastern counties are on the extreme western cusp of the nation’s so-called “Tornado Alley” – the stretch of southeastern and plains states that see the most tornadoes outside of Florida. Being on the cusp, Colorado sees fewer and weaker instances than regions at the center of Tornado Alley, but don’t let that fool you. The state is still ranked as the 10th most active in the nation for tornadoes, averaging 52 per year, and at least one category EF-3 tornado has touched down in recent history, resulting in severe property damage. Weld and Adams counties have seen the highest frequency overall, while over 250 total injuries and five total deaths have been attributed to tornadoes in the state.

Current Year and Current Trend

Thankfully for the Centennial State, the 2021 tornado season is shaping up to be a strange one. The development of a La Niña pattern with a strong northern jet stream has joined with colder-than-average temperatures in the central and eastern Tropical Pacific and extreme drought conditions in the Four Corners region (Colorado, Utah, Arizona, New Mexico) to effectively push the predicted epicenter of tornado activity much farther east than it’s typically found. As a result, meteorologists predict that Tornado Alley will actually see below-average tornado activity, while the Mississippi and Tennessee valleys, along with much of the mid-Atlantic, will take the brunt of the severe weather that so often precipitates tornadoes.

Even so, at least some tornado activity is likely to happen in Colorado this year, though research does show an overall eastern shift of the drier climate in the United States, which may bring much more tornado activity to areas east of Mississippi on a regular basis. Regardless, a variety of research shows that “there has been a subtle but detectable increase in tornado risk over the past few decades,” and that the actual number of tornadoes in large outbreaks is only increasing. While the boundaries of Tornado Alley may be expanding eastward, the risk of tornado activity in Colorado won’t go away anytime soon.

Do’s and Don’ts

So what should you do to prepare for a tornado, and what should you do in the event of one? To ensure personal safety:

Be prepared with an emergency 72-hour kit that contains water, non-perishable food, first aid supplies, and essential medications
Keep a list of important contact information (like phone numbers) with your emergency kit
Purchase a battery-operated radio or TV so that you can keep apprised of weather alerts, even without power
Develop a plan with your family and employees so that everyone knows where to take shelter in your district offices or at home
Know the best places to shelter, including basements, bathrooms, closets, or center hallways
Watch or listen for weather alerts and warnings from your local weather station or a federal station, like NOAA’s radio channel during a severe weather event
Be on the lookout for signs of a possible tornado, including a dark or green sky, low-lying clouds, hail, and roaring wind
Avoid windows and foundationless structures like mobile homes when sheltering
Find the nearest building and take immediate shelter if a tornado hits while you are outside or driving; do not try to outrun the tornado

To aid in your district’s tornado preparedness, remember the tips we offer in previous articles:

A tornado watch and tornado warning are not the same: a tornado watch signifies that a tornado is possible, while a tornado warning indicates visual or radar confirmation of a tornado
Tornadoes may be transparent until they gather enough dust and debris to become visible. But even transparent, they are still very dangerous
On average, tornadoes move from the southwest to the northeast, but they have been known to move in any direction
Tornadoes typically move around 30 mph but have been clocked at 70 mph
In Colorado, tornadoes are most common in spring and summer months east of the Rocky Mountains between 3 p.m. and 9 p.m., but they can occur anytime. If a Tornado Watch has been issued for your area, remain vigilant
FEMA provides designs and guides on building safe rooms for extreme wind events, which can help you shore up shelter areas
FEMA also offers a collection of guides on how to protect your property from high winds generated by tornadoes or hurricanes, including how to reinforce garage doors, protecting windows and doors, securing composite shingle and single-ply roofs, and more

Additional Resources