NWS: 11 tornadoes touched down in northern Illinois on Tuesday night, one in Lee County

DIXON – The National Weather Service is reporting that at least 11 confirmed tornadoes touched down Tuesday night when a band of thunderstorms moved through northern Illinois.

The NWS’s Chicago office announced Wednesday that tornados were confirmed in Lee, DeKalb, Kane, Cook and Lake counties in Illinois, as well as Lake County, Indiana.

The severe line of thunderstorms developed Tuesday afternoon over northwestern Illinois and spread east throughout the evening across the Chicago metropolitan area. A tornado watch was issued at 3:54 p.m. from the Quad Cities’ office in Davenport, Iowa, with the NWS Chicago office later issuing multiple tornado and severe thunderstorm warnings for large hail and damaging winds.

Hail up to 2 inches in diameter was reported in some areas.

All of the tornadoes in Illinois have been rated either an EF-0 or EF-1. An EF-0 tornado has estimated wind speeds of between 65 and 85 mph. EF-1 tornadoes have estimated wind speeds of between 86 and 110 mph.

Information about Tuesday night’s tornadoes, their locations and EF ratings, as provided by the NWS, are:

• Compton tornado, Lee County: EF-0.
• Waterman tornado, DeKalb County: EF-0.
• Hinckley to Big Rock tornado, DeKalb/Kane counties: EF-0.
• Sugar Grove to Batavia tornado, Kane County: EF-1.
• Elburn to Campton Hills tornado, Kane County: EF-0.
• Geneva tornado, Kane County: EF-1.
• Gary tornado, Lake County, Indiana: EF-1.
• South Barrington tornado, Cook County: EF-0.
• Inverness tornado, Cook County: EF-1.
• Mundelein tornado, Lake County, Illinois: EF-1.
• Hoffman Estates tornado, Cook County: EF-0.

Notably, in 2023 there were 58 tornadoes in the NWS Chicago forecast area, which is the most to ever occur there in a calendar year since official NWS tornado records began in 1950.

The previous record for the most tornadoes in a calendar year in the NWS Chicago forecast area was 30 in 2015, and the 10- to 20-year average is about 15. In addition to the large number of tornadoes in 2023, there were other noteworthy tornado statistics, according to the NWS:

• 2023 is the first year in which tornadoes occurred in the months of January, February and March of the same year in the NWS Chicago forecast area.
• July 2023 featured a record number of tornadoes – 27 – in the NWS Chicago forecast area. The previous record was four in 1993.
• For the first time on record, all 23 counties in the NWS Chicago forecast area had at least one tornado occur in the same calendar year.
• There were three days with more than 10 tornadoes each in the NWS Chicago forecast area in 2023, which is the first time on record that this has happened. In fact, before 2023, there had never been more than two days with more than 10 tornadoes in the NWS Chicago forecast area in the same calendar year. Including 2023, the forecast area has only had 16 calendar days with more than 10 tornadoes.
• There also were a record number of EF-1 or stronger rated tornadoes – 21 – in the NWS Chicago forecast area in 2023, breaking the previous record of 19 from 1965.

Looking ahead

Even after storms and rain rolled through the region Tuesday night, a hazardous weather outlook issued Wednesday by the National Weather Service indicated that there remained an elevated fire risk in Winnebago, Boone, McHenry, Lake, Ogle, Lee, DeKalb, Kane, DuPage, La Salle, Kendall, Grundy, Kankakee, Livingston, Iroquois, Ford, Cook and Will counties.

There is a limited thunderstorm risk expected Monday, but gusty winds and a drier airmass may result in elevated fire weather conditions Tuesday.