Can tornadoes happen in the cold season?

Severe weather, including tornadoes, can happen any time of the year if the conditions are ripe. This is exactly what happened in Fultondale, Alabama late Monday night. The tornado flipped cars and tore roofs off homes while many were sleeping. As of Tuesday afternoon, the tornado has been rated a high-end EF2 with winds of 135 mph. Surveys are still ongoing in the area.

While tornadoes aren’t as common in the cold season, they can happen.  Look at the image which shows the tornado probabilities for the U.S. around Jan. 29. You can see there’s an area in the South where probabilities increase, compared to the rest of the country. Climatology dates from 1982 to 2011.

Now look at the image that shows the probabilities in June. Tornadoes do peak in the spring and summer across the nation as the atmosphere warms. However, it’s important to know that the geographical area does shift throughout the year.

In western Pennsylvania, the peak months for tornadoes are May, June, and July. June is the peak month which frequents 86 tornadoes in the NWS Pittsburgh warning area. This area includes western Pennsylvania, parts of Ohio, West Virginia, and Maryland. Data is from 1950-2018.

While the peak of severe weather season for our area is in late spring and summer, tornadoes can happen in January.

I dug through the database and most recently, there was an EF1 tornado with winds of 95 mph that hit Mercer County in Jan. 2019. On Feb. 15, 2018, a tornado hit Uniontown in Fayette County. A tornado hit Greensburg in Dec. 2006.

Tornadoes form from severe thunderstorms when warm, moist air is present in the atmosphere and other parameters are met. There needs to be enough lift in the atmosphere to get storms to build, such as a cold front or upper air support. Wind shear, or the increase in speed of the wind with height and a change in wind direction with height also needs to be present.

Even though you may not expect a tornado to happen in the winter, it’s important to stay alert to your local forecast because they can, and have been known, to happen.

At least 1 dead after tornado, severe storms hit Alabama (NCD)

Cox Media Group