Peoria, Ill (WMBD) — When it comes to severe weather in Illinois, 2023 has been off to roaring start with more than 70 tornadoes already reported statewide. While there were a few cold season events in January and February that spawned tornadoes across the state, severe weather events on March 31st and April 4th really led the charge in leading the way to what has already been an active severe weather season.
March 31st Severe Weather Outbreak
Producing 161 tornadoes nationwide, 49 in Illinois, this outbreak has been the biggest of the year so far. Most of the tornadoes that developed impacted areas along and north of I-80 while another group of storms brought several tornadoes to communities along I-72. One supercell moved north through the Illinois River Valley bringing large hail up to 2.00″ in diameter to the Peoria Metro Area. It also produced a handful of weak tornadoes from Mason County to Livingston County, including an EF-1 near Deer Creek.
April 4th Severe Weather Outbreak
While this particular outbreak was not as widespread as the March 31st event, it was more impactful to our local area. So far the National Weather Service has confirmed that 5 tornadoes impacted McDonough and Fulton Counties, including a strong EF-3 that went through Lewistown and Bryant. The storm injured 4 people but thankfully there were no fatalities.
Illinois Tornadoes on Average
According to the Storm Prediction Center, Illinois has seen 76 tornadoes since the start of the year. While these reports are preliminary, and some are likely duplicates, that number is unlikely to drop significantly as event reviews are completed in the weeks ahead. If we were to see our monthly average number of tornadoes for the remainder of the year, Illinois would be on track to eclipse 115 tornadoes, which would be the most since 2006 when 123 tornadoes were reported across the state.
Based on the 20 year, average Illinois experiences about 57 tornadoes a year with April, May and June being the most active months.
Illinois Tornado Trends
Illinois has seen an uptick in tornadoes in the past several decades. According to the University of Illinois, since the early 1950s there has been an increase in both the total number of tornadoes and the number of stronger tornadoes (EF-1 to EF-5). There is a more noticeable increase in the number of EF-0 tornadoes, this is mostly from an improvement in radar technology and an increase in spotter reporting. While these weaker tornadoes make up a larger part of the overall increase, there is still an increase in severe tornadoes rated EF-1 to EF-5 over the same time period.
Along with this general increase in overall tornadoes for the state, a recent study suggest that there has been an overall shift in what is commonly referred to as “Tornado Alley”. The Central Plains (areas like Oklahoma, Nebraska, and Kansas) have been associated with the phrase for decades. Since the late 70s there has been an increase in the number of tornadoes per decade in areas like far southern Illinois and Indiana, western Kentucky, and northern Tennessee. Over this same time period, there has been a general decrease in tornadoes over areas in the Central Plains. While this doesn’t necessarily mean that the location of tornado Alley is moving, is does highlight the overall shift in where these storms are happening.