The end of El Niño could ramp up tornadoes in Iowa. What to expect this year.

Kate Kealey, Des Moines Register
·3 min read

Spring started with a vengeance in Iowa in 2023. March had more tornadoes than any other month in Iowa during 2023. This spring season may be the opposite. Long-range forecasters warn of a slow start to severe weather season that will escalate as the year progresses.

Springtime weather patterns will contribute to severe weather throughout Tornado Alley, covering states from Texas through Nebraska, according to AccuWeather.

"The second half of spring is jumping out to us," said Senior Meteorologist Paul Pastelok about the upcoming tornado activity.

More: A 2023 Iowa weather recap: Drought, tornado outbreaks and massive hail

What will this tornado season look like?

Long-range forecasters at AccuWeather are predicting 1,250 to 1,375 tornadoes across the United States in 2024.
Long-range forecasters at AccuWeather are predicting 1,250 to 1,375 tornadoes across the United States in 2024.

Last year's weather season broke norms for severe weather season. In March, 206 tornadoes swept through the country. This is more than double the monthly historical average of 80, according to AccuWeather.

"The severe weather threat can be more frequent in the Midwest, Tennessee and Ohio valleys later March into May, while the northern Plains and Northeast can have an increase in May," Pastelok said.

Tornadoes this year are also expected to near historic average of 1,225. AccuWeather predicts anywhere from 1,250 to 1,375 tornadoes across the country in 2024. That's a downturn from the 1,423 reported in 2023.

More: Farm insurer joins others in pulling back from Iowa after increased storms

When is the highest risk for tornadoes in Iowa?

Spring tornado risk across the U.S. from March through May 2024.
Spring tornado risk across the U.S. from March through May 2024.

The month of May will have the highest risk for tornadoes in Iowa due to a change in weather patterns from the western and central Gulf of Mexico causing higher dewpoints and humidity.

"In addition, the southern storm track, impacting the Gulf Coast which lift north and meeting up with the northern storm track putting the central Plains and Midwest in a good path for strong severe weather events," Pastelok said in an email to the Register.

Severe weather can still occur throughout March and April. From March 24 to March 29, Pastelok predicted potential severe weather including damaging wind gust, hail and some tornadoes. While April could have a high frequency of storms or cold fronts.

How many tornadoes were there in Iowa during 2023?

In 2023, 72 tornadoes touched down in Iowa, according to the National Weather Service. Last year had a little more than 20 tornadoes above normal.

2023 was also the earliest start to tornado season since the start of tornado recording in 1950, with two touching down on Jan. 16, 2023 in eastern Iowa, according to the NWS Iowa Tornado summary. March was the peak month for tornadoes in Iowa 2023. There were 25 tornadoes that swept different areas of the state that month.

Database: Track all of the tornaodes in Iowa since 1950

How many injuries were there in Iowa due to tornadoes in 2023?

In Iowa, there were 11 injuries due to tornadoes in 2023. Zero casualties occurred last year because of tornadoes, according to the NWS.

May could be 'critical month' for tornadoes: Why severe weather could increase as the year progresses?

El Niño predicted to conclude in the next few months. The El Niño season caused below average tornadoes and hail. There could be more activity in Tornado Alley during April and into May, according to AccuWeather. The temperatures of the Gulf of Mexico are near to slightly above historical averages, which can dictate severe weather season.

"If the water is slower to warm in March, this could hold back the number of severe weather reports in March, especially compared to March 2023," Pastelok said.

As the Gulf of Mexico temperature increases later into spring, May could be a "critical month for tornadoes."

"The season overall for the spring, for the entire nation will average near normal on severe weather reports but slightly below average on tornadoes (mainly due to the later start of high frequency tornado events)," Pastelok told the Register in an email Friday. "The number of tornadoes can pick up during the summer and the late season severe weather period in the fall."

More: It's official: February 2024 was the warmest-ever in Des Moines weather history

Kate Kealey is a general assignment reporter for the Register. Reach her at kkealey@registermedia.com or follow her on Twitter at @Kkealey17.

This article originally appeared on Des Moines Register: Tornado season is near. Here's Iowa's spring weather prediction