A tornado forms when a thunderstorm creates lifting force and unstable air. Inside a thundercloud, warm, humid air rises along with rain and hail.
Tornadoes can form any time of year. However, June and July are the peak months for tornadoes in Minnesota.
In Minnesota, tornadoes are most likely to occur in late spring and early summer, but they can also happen any time of the year. According to the National Weather Service, tornadoes are most likely when thunderstorms develop in warm, moist air ahead of an eastward moving cold front.
The warmer and drier weather of spring and summer allows the jet stream to shift, which can lead to increased changes in temperature. In addition, storms tend to strengthen and grow larger as they move west across the United States.
As a result, severe thunderstorms can develop and produce damaging winds, large hail and isolated tornadoes. Several thunderstorms have already been reported in Minnesota, including one that touched down in Willmar on Sunday night.
A tornado watch is in effect for much of the lower half of the state, including Hennepin and Ramsey counties, until midnight Monday. The National Weather Service says the tornado that hit Willmar is considered an EF1-sized twister.
While tornadoes can happen at any time of year, they’re typically most common in late spring and early summer. During these dangerous weather events, it’s essential to have an emergency plan in place to protect yourself and your loved ones.
The most effective plan includes knowing where you can find shelter during a tornado outbreak. This can be a home, barn, or other building that’s sturdy enough to withstand windy conditions.
In addition, it’s important to have a disaster kit with you during a severe storm. This should include items like water, food and extra clothes.
It’s also helpful to have a list of important phone numbers, including the local weather forecast office and National Weather Service office in your area. This will help you communicate with local authorities during a severe storm and can make a difference in how quickly you’re able to get help.
Tornadoes are caused by a series of weather conditions that come together to produce the violent storm. They begin with thunderstorms that form in warm, moist air near a dryline.
They then rise up into a cloud called a "wall cloud," and as they continue to rise, they can eventually spin out a tornado.
Minnesota has a high risk for tornadoes in the spring and summer as warm, moist air flows up into the state. These weather conditions usually develop along frontal systems that move east from the central United States.
These strong thunderstorms sometimes produce large hail, damaging winds, and tornadoes.
In the winter and early spring, tornadoes occur with thunderstorms that develop in warm, moist air in advance of eastward-moving cold fronts.
The risk of tornadoes in Minnesota diminishes as the spring and summer seasons progress, but the threat of outbreaks remains. The peak tornado season in the state is June, followed by July, May and August.
To be prepared for tornadoes, it’s important to develop a tornado plan that includes a list of emergency contacts and essential documents. These items can be important if you need to evacuate your home or file an insurance claim following a tornado.
It’s also a good idea to store your most important papers in a fire-and-water-proof safe, such as birth certificates, social security cards and insurance policy information. These documents are often difficult to replace if they’re lost during a tornado.
Schools, shopping centers, nursing homes, hospitals, sports arenas and other buildings should have a tornado safety plan in place. It should include pre-designated shelter areas and easy-to-read signs to direct people to the safest places.
The best places to seek shelter are interior hallways or rooms without windows. These are typically located on the lowest floors of buildings and in townhomes.