EF1 tornado, Thomas to The Burg, Illinois, March 31, 2023

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mphthis tornado

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF1

Date

March 31, 2023

Touchdown

6:48 PM CDT (23:48 UTC)

Lifted

7:01 PM CDT (00:01 UTC)

On the ground

13 minutes

Path length

13.9 miles (22.3 km)

Path width

150 yards (137 m)

Deaths

0

Injuries

0

Counties

Whiteside, Bureau and Lee counties

Touchdown point

41.550, -89.770

Lift-off point

41.629, -89.523

Record number

2303311748-01

40 damage points were recorded along this path by NWS DVN and NWS LOT, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 122 mph.

• Outbuilding damage was not complete, but pieces were flung quite some distance. Also two sizeable trees snapped near the base. No damage to home immediately adjacent.
• Tree uprooted and heavy damage to an outbuilding.
• Also large softwood tree downed.
• While broken at the bottom, it appeared to be more heavily bent and then snapped (didn't break free from the wires).

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A very strong system developed on the morning of March 31st and tracked across the state of Iowa. This system pulled unseasonably warm and moist air into the Midwest, which combined with a very favorable wind profile to create a volatile environment for severe thunderstorms. Discrete supercell thunderstorms occurred initially, but quickly transitioned into a QLCS mode. This system produced a historic tornado outbreak for the area, with a record 29 tornadoes on the day, including 13 rated EF-2, 1 rated EF-3, and 1 rated EF-4. This was the first EF-4 tornado in the NWS Quad Cities service area since 1995. 11 injuries were reported, with no known fatalities. In addition to the numerous tornadoes, there were many large hail and damaging wind reports. Maximum straight line thunderstorm winds were estimated at 80 to 90 mph.

During the afternoon and evening of the 31st, a wave of severe thunderstorms produced numerous tornadoes, severe hail, extensive wind damage, and localized flooding across northern and northeastern Illinois. A total of 37 tornadoes were confirmed across the state. The NWS Chicago office tied a record for the most tornadoes to occur in a single calendar day within the office's county warning area with 22, 17 of which occurred in Illinois. One EF-2 tornado occurred in south-central Lee County and two others in northwest Indiana. Some of the more notable damage includes multiple semi trucks blown over, a garage that had been completely destroyed southeast of Amboy, and the partial roof collapse of the Apollo Theatre in Belvidere which unfortunately resulted in one fatality and 40 injuries.

A tornado developed north of Atkinson, in Henry County, and tracked northeast towards Hooppole, then tracking more easterly for another mile where it ended in western Bureau County. The tornado crossed into Bureau County about a third of a mile north of Highway 23, on 00 E St, then lifted about one mile to the E/NE. The tornado was rated EF-2 in Henry County, and EF-1 in Bureau County.

This tornado began just south of Illinois highway 92 in northwest Bureau county in the NWS Quad Cities county warning area. It then moved into far southeast Whiteside county, near the intersection of Osage Road and 1050 St E. The tornado tracked for 2 miles in Whiteside County, before moving into Lee County, about a half mile south of the Green River. This tornado would continue for 6 additional miles into southwest Lee County (see NWS Chicago StormData). The damage from this tornado included numerous heavily damaged outbuildings, several snapped power poles, and dozens of trees. The worst damage was to a large farmstead outbuilding on the Whiteside and Bureau County border area, with the roof and two of the four walls destroyed and debris slung well into a field. Peak winds with this tornado were estimated at 110 mph. The tornado was rated EF1 in Bureau and Whiteside Counties.

This tornado began just south of Illinois highway 92 in northwest Bureau County, then moved into far southeast Whiteside county, near the intersection of Osage Road and 1050 St E. The tornado tracked for 2 miles in Whiteside County, before moving into Lee County, about a half mile south of the Green River. This tornado would continue for 6 additional miles into southwest Lee County (see NWS Chicago StormData). The damage from this tornado included numerous heavily damaged outbuildings, several snapped power poles, and dozens of trees. The worst damage was to a large farmstead outbuilding on the Whiteside and Bureau County border area, with the roof and two of the four walls destroyed and debris slung well into a field. Peak winds with this tornado were estimated at 110 mph. The tornado was rated EF1 in Bureau and Whiteside Counties.

This tornado began just south of Illinois Highway 92 in northwest Bureau County. It then tracked through far southeast Whiteside County within 3 miles of the town of Deer Grove. This tornado would continue for 6 additional miles into southwest Lee County, where it dissipated near Maytown Road and Atkinson Road. The damage from this tornado included numerous heavily damaged outbuildings, several snapped power poles, and dozens of trees. The worst damage was to a large farmstead outbuilding along the Whiteside-Bureau county line with the roof and two of the four walls destroyed and debris slung well into a field.

The tornado touched down in the Woodhaven Lakes campground south of Amboy. There, multiple campers were damaged by the tornado including two that were rolled. Farther along its northeastward track, two trees had fallen onto a home destroying it. The tornado appeared to have reached its maximum intensity with wind speeds estimated at 115 mph shortly after crossing US Hwy 52 where it destroyed a large garage and snapped several trees at their trunks. Several dozen other large trees were snapped and many branches sheared off along its path. Toward the end of its lifespan, the tornado also did minor damage to an outbuilding before lifting near Butler Hill Rd north of West Brooklyn.

This tornado developed just south of the town center of Sublette snapping multiple utility poles as it crossed US Rt. 52. The tornado strengthened as it progressed into the town of West Brooklyn. There, it downed several large trees, folded an approximately 120-foot tall tower, and tore the roof off of a bank in downtown West Brooklyn. A wooden beam from the roof of the bank impaled a nearby garage roof to the north-northeast of the bank. The tornado then lifted north of Shaw Rd just west of Carnahan Rd just over 2 miles northeast of West Brooklyn.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

19 minutes of warning. NWS DVN issued a tornado warning for this county at 23:29 UTC, 19 minutes before the tornado touched down, in force until 00:00 UTC.

The county was under a tornado watch, issued at 16:47 UTC and running to 01:00 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Moderate Risk, with a 0.15 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 19:54 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Sterling Rockfal (SQI), 17 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Quad Cities radar (KDVN), 78 km away, was scanning. The volume nearest the touchdown began at 23:48 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2023 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

126 more were confirmed in the United States that day.

All 127 of them

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.