Tornadoes · United States · Illinois · 2020

EF1 tornado, Chana, Illinois, May 23, 2020

This EF1 tornado ran 0.3 miles across Ogle County on May 23, 2020, touching down at 4:30 PM CDT and reaching 100 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  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.

The record

Rating
EF1
Date
May 23, 2020
Touchdown
4:30 PM CDT (21:30 UTC)
Lifted
4:32 PM CDT (21:32 UTC)
On the ground
2 minutes
Path length
0.3 miles (0.5 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
County
Ogle County
Touchdown point
41.967, -89.243
Lift-off point
41.970, -89.239
Record number
2005231530-01

The damage survey

2 damage points were recorded along this path by NWS LOT, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 100 mph.

  • Multiple damage indicators at this location suggesting 90 to 100 mph winds.
  • Several damage indicators at this location.

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

What the Weather Service recorded

Scattered severe thunderstorms moved across northern Illinois during the afternoon of May 23rd producing wind damage, localized flooding and three tornadoes. Several funnel clouds were also reported.

A tornado touched down near the intersection of S Rocky Hollow and E Canfield Roads. Peak winds were estimated between 90 mph and 100 mph based on damage to outbuildings and two farmsteads that were significantly damaged. There were also several trees and utility poles blown down.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

The county was under a tornado watch, issued at 17:33 UTC and running to 23:55 UTC.

Issued (UTC)ExpiredProductOffice
17:33 UTC23:55 UTCTornado WatchLOT
18:33 UTC19:15 UTCSevere Thunderstorm WarningLOT
19:07 UTC19:30 UTCSevere Thunderstorm WarningLOT
19:26 UTC20:30 UTCSevere Thunderstorm WarningLOT
19:44 UTC20:30 UTCSevere Thunderstorm WarningLOT
02:20 UTC14:02 UTCFlood AdvisoryLOT

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 forecast that day

The Storm Prediction Center had this point in a Enhanced Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 19:55 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 air that afternoon

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.

Davenport, (KDVN), 12:00Z

9.5 hours before the tornado, 111 km from the path. May 23, 2020.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2020-05-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 145 joules per kilogram, CIN -133, lifted condensation level 859 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 12:00Z on 2020-05-23The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 148 square meters per square second, 0 to 6 km bulk shear 36 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
145 J/kg
Mixed-layer CIN
-133 J/kg
Surface CAPE
1 J/kg
Mixed-layer LCL
859 m above ground
0-6 km bulk shear
36 kt
0-1 km bulk shear
21 kt
0-1 km storm-relative helicity
148 m²/s²
0-3 km storm-relative helicity
198 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2
0-3 km lapse rate
4.7 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 00:00Z

2.5 hours after it, 111 km from the path. May 24, 2020.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2020-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -16, lifted condensation level 1245 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 00:00Z on 2020-05-24The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 23 square meters per square second, 0 to 6 km bulk shear 13 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-16 J/kg
Surface CAPE
230 J/kg
Mixed-layer LCL
1245 m above ground
0-6 km bulk shear
13 kt
0-1 km bulk shear
6 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.0 K/km

Open this sounding in Storm Lab

The radar

The Chicago radar (KLOT), 104 km away, was scanning. The volume nearest the touchdown began at 21:31 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.

What was reported nearby

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

Time (UTC)ReportWhereCountyRemark
19:29 UTCTORNADO1 Sse MalvernWhiteside, ILBRIEF TOUCHDOWN. NO DAMAGE OBSERVED.
19:46 UTCTSTM WND DMG3 Ene ColetaWhiteside, ILPOWER LINES DOWN ACROSS ROADWAY. 14 INCH TREE DIAMETER TREE SNAPPED. POSSIBLE TORNADO DAMAGE. TIME ESTIMATED FROM RADAR.
19:47 UTCTSTM WND DMG3 Ene ColetaWhiteside, ILDELAYED REPORT. REPORT OF WIRES DOWN AND DAMAGE TO A HOME; SHINGLES OFF THE ROOF. POSSIBLE TORNADO DAMAGE. TIME ESTIMATED FROM RADAR.
19:49 UTCTORNADO3 Se MilledgevilleCarroll, ILBRIEF TORNADO TOUCHDOWN SOUTHEAST OF MILLEDGEVILLE, HAS SINCE LIFTED. HAVE HAD SEVERAL REPORTS OF BRIEF TOUCHDOWNS.
19:53 UTCTSTM WND GST 602 Wnw WinnebagoWinnebago, ILSPOTTER REPORT OF QUARTER SIZE HAIL AND 60 MPH NW OF WINNEBAGO.
19:56 UTCHAIL 13 Wnw WinnebagoWinnebago, IL
20:00 UTCFUNNEL CLOUD3 Wsw PoloOgle, ILSPOTTER REPORTS AND SOCIAL MEDIA PHOTOS OF MULTIPLE FUNNEL CLOUDS IN WESTERN OGLE COUNTY.
21:30 UTCTSTM WND DMG1 Sw ChanaOgle, ILBARN HEAVILY DAMAGED. POSSIBLE BRIEF TORNADO GIVEN FUNNELS IN THE REGION, BUT HAVE NOT HAD CONFIRMATION. LOCATION OF DAMAGE RELATIVE TO RADAR ROTATION AND STORM STRUCTURE INDICATES IT COULD HAVE BEEN REAR-FLANK DOWNDRAFT
21:30 UTCTORNADO1 Wsw ChanaOgle, ILEF-1 TORNADO BEGAN AT APPROXIMATELY 430 PM CDT ON MAY 23RD NEAR THE INTERSECTION OF S. ROCKY HOLLOW RD. AND E. CANFIELD RD. (41.97, -89.24). PATH LENGTH OF APPROXIMATELY 0.3 MILES AND ESTIMATED WIDTH OF 100 YARDS. PEAK W
22:02 UTCHEAVY RAIN 1.53 Sw WinneshiekStephenson, ILRAINFALL TOTAL. STORMS HAVE ENDED.
23:12 UTCTORNADO5 Ne GenoaDe Kalb, IL40 X 20 BARN DAMAGES WITH DEBRIS BLOWN DOWNSTREAM INTO A FIELD, POWER LINES DOWN ABOUT A MILE DOWNSTREAM, LIKELY TORNADO PATH BASED ON SPOTTER REPORTS AND RADAR.
23:12 UTCTORNADO5 Ne GenoaDe Kalb, ILLIKELY BEGAN NEAR MELMS AND POLK RD. 40 X 20 BARN DAMAGED WITH DEBRIS BLOWN DOWNSTREAM INTO A FIELD, AND POWER LINES DOWN ABOUT A MILE DOWNSTREAM. TORNADO WAS LIKELY VERY SHORT LIVED.
23:12 UTCTORNADO5 Ne GenoaDe Kalb, ILTORNADO BEGAN NEAR MELMS AND POLK RD. 40 X 20 BARN DAMAGED WITH DEBRIS BLOWN DOWNSTREAM INTO A FIELD, AND POWER LINES DOWN ABOUT A MILE DOWNSTREAM. TORNADO DISSIPATED BEFORE REACHING I-90.
23:45 UTCFLASH FLOODGenoaDe Kalb, ILCREEKS OUT OF THEIR BANKS WITH 2 TO 3 FEET OF WATER OVER SOME ROADWAYS IN TOWN.

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

This ground now

The live radar over the trackEvery 2020 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

The other tornadoes of May 23, 2020

13 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 2312:30 PM CDTEF1Johnson, IA7.050
May 2312:57 PM CDTEF1Cedar, IA6.930
May 231:20 PM CDTEF0Clinton, IA1.220
May 231:53 PM CDTEF0Jackson, IA1.420
May 231:54 PM CDTEF0Woodford, IL3.575$20,000
May 232:24 PM CDTUnratedJackson, IA0.010
May 232:29 PM CDTEF1Whiteside, IL12.330
May 232:53 PM CDTEF0Kendall, IL6.31001
May 234:18 PM CDTUnratedJo Daviess, IL0.520
May 236:06 PM CDTEF0Kane, IL3.250
May 236:14 PM CDTUnratedGarza, TX0.430
May 236:52 PM CDTEF0Benson, ND0.120
May 236:07 PM MDTUnratedSherman, KS1.150

What this means

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.

Sources

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