Tornadoes · United States · Illinois · 2023
EF1 tornado, Saint Clair County, Illinois, April 15, 2023
This EF1 tornado ran 3.0 miles across Saint Clair County on April 15, 2023, touching down at 7:03 PM CDT and reaching 200 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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- April 15, 2023
- Touchdown
- 7:03 PM CDT (00:03 UTC)
- Lifted
- 7:07 PM CDT (00:07 UTC)
- On the ground
- 4 minutes
- Path length
- 3.0 miles (4.9 km)
- Path width
- 200 yards (183 m)
- Deaths
- 0
- Injuries
- 0
- County
- Saint Clair County
- Touchdown point
- 38.520, -89.987
- Lift-off point
- 38.545, -89.942
- Record number
- 2304151803-02
The damage survey
60 damage points were recorded along this path by NWS LSX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 100 mph.
- Roughly 1/4 mile east of the main road
- Car port blown up and over house
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
The warnings
29 minutes of warning. NWS LSX issued a tornado warning for this county at 23:34 UTC, 29 minutes before the tornado touched down, in force until 00:15 UTC.
The county was under a tornado watch, issued at 21:05 UTC and running to 01:11 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 21:05 UTC | 01:11 UTC | Tornado Watch | LSX |
| 23:19 UTC | 00:00 UTC | Tornado Warning | LSX |
| 23:27 UTC | 00:19 UTC | Severe Thunderstorm Warning | LSX |
| 23:34 UTC | 00:15 UTC | Tornado Warning | LSX |
| 23:39 UTC | 00:30 UTC | Tornado Warning | LSX |
| 00:09 UTC | 00:26 UTC | Tornado Warning | LSX |
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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:52 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.
Lincoln, IL (KILX), 00:00Z
0.1 hours before the tornado, 215 km from the path. April 16, 2023.
- Mixed-layer CAPE
- 647 J/kg
- Mixed-layer CIN
- -32 J/kg
- Surface CAPE
- 863 J/kg
- Mixed-layer LCL
- 1647 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- -5 m²/s²
- 0-3 km storm-relative helicity
- 107 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 7.7 K/km
Lincoln, IL (KILX), 12:00Z
11.9 hours after it, 215 km from the path. April 16, 2023.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -99489 J/kg
- Surface CAPE
- 12 J/kg
- Mixed-layer LCL
- 660 m above ground
- 0-6 km bulk shear
- 70 kt
- 0-1 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- -75 m²/s²
- 0-3 km storm-relative helicity
- -118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 3.9 K/km
The radar
The St Louis radar (KLSX), 65 km away, was scanning. The volume nearest the touchdown began at 00:02 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 23:34 UTC | TORNADO | 1 Ese Chalfin Bridge | Monroe, IL | A WEAK TORNADO TRAVELED 16.3 MILES ACROSS MONROE COUNTY, ILLINOIS BETWEEN 6:34 PM AND 6:56 PM. THE TORNADO BEGAN NEAR THE MISSISSIPPI RIVER SOUTHWEST OF MAEYSTOWN AND TRAVERSED RURAL AREAS CAUSING SPORADIC TREE AND STRUC |
| 23:39 UTC | TORNADO | 3 Sw Valmeyer | Monroe, IL | A WEAK EF0 TORNADO DEVELOPED IN THE FLOOD PLAIN OF THE MISSISSIPPI RIVER SOUTHWEST OF VALMEYER, IL AND MOVED NORTHEAST FOR FIVE MILES. MINOR TREE DAMAGE AND STRUCTURAL DAMAGE OCCURRED TO OUTBUILDINGS. THE MAXIMUM WIDTH W |
| 23:43 UTC | TSTM WND DMG | Madonnaville | Monroe, IL | IMAGES FROM TWITTER SHOW MULTIPLE LARGE TREES AND TREE BRANCHES SNAPPED AT A RESIDENCE IN MADONNAVILLE OFF OF AHNE ROAD. PORTIONS OF A TIN ROOF OF AN OUTBUILDING ON THE PROPERTY APPEAR TO BE DAMAGED AS WELL. |
| 23:44 UTC | TSTM WND DMG | 2 Wsw Foster Pond | Monroe, IL | IMAGES IN A LOCAL NEWS STORY SHOWS A TREE DOWN ALONG HIGHWAY 156 NEAR VALMEYER. TIME ESTIMATED FROM RADAR. |
| 23:45 UTC | TSTM WND GST 67 | 1 Ssw Roxana | Madison, IL | |
| 23:48 UTC | HAIL 1 | 1 W Valmeyer | Monroe, IL | REPORT FROM MPING: QUARTER (1.00 IN.). |
| 23:55 UTC | TORNADO | Hecker | Monroe, IL | NUMEROUS TREES DOWN. SEVERAL OUTBUILDINGS DESTROYED. |
| 23:57 UTC | TSTM WND GST 50 | 1 Nne Waterloo | Monroe, IL | DIME SIZED HAIL ALSO OBSERVED. |
| 23:58 UTC | TSTM WND GST 56 | 1 Sse Sauget | St. Clair, IL | KCPS ASOS. |
| 00:00 UTC | TSTM WND DMG | 1 Ene Foster Pond | Monroe, IL | TREES DOWN ALONG ROUTE 156. |
| 00:02 UTC | TSTM WND DMG | 2 E Centreville | St. Clair, IL | WIDESPREAD TREE DAMAGE ON SIGNAL HILL BLVD. SEVERAL LARGE TREES BLOWN DOWN, NUMEROUS LARGE TREE LIMBS DOWN. SOME DAMAGE TO HOMES DUE TO FALLEN TREES. SEVERAL POWER LINES KNOCKED DOWN. VIA EMAIL REPORT WITH PICTURES. |
| 00:02 UTC | TSTM WND DMG | Belleville | St. Clair, IL | PICTURE FROM SOCIAL MEDIA SHOWS LARGE TREE BLOWN DOWN AND MULTIPLE LARGE LIMBS DOWN IN BELLEVILLE. |
| 00:02 UTC | TORNADO | 3 W Collinsville | Madison, IL | BROADCAST METEOROLOGIST WITNESSED BRIEF TOUCHDOWN JUST WEST OF OF I-255/70 INTERCHANGE IN COLLINSVILLE. |
| 00:03 UTC | TORNADO | 1 Se Belleville | St. Clair, IL | A WEAK EF0 TORNADO TRAVELED NORTHEAST THROUGH SWANSEA, IL STARTING ON WEST E STREET JUST WEST OF NORTH 5TH STREET. TREE DAMAGE AND MINOR STRUCTURAL DAMAGE WAS NOTED ALONG THE 1.12 MILE PATH WITH A MAXIMUM WIND SPEED OF 8 |
| 00:03 UTC | TORNADO | 1 Se Belleville | St. Clair, IL | A WEAK EF1 TORNADO FORMED JUST WEST OF IL ROUTE 159 ON WEST F STREET. IT TRAVELED TO THE NORTHEAST TO ADELINE DRIVE JUST WEST OF NORTH GREEN MOUNT ROAD. MINOR DAMAGE TO TREES AND STRUCTURES WERE NOTED. THE TORNADO HAD MA |
| 00:05 UTC | TSTM WND DMG | 2 Se Fairview Heights | St. Clair, IL | IMAGE FROM FACEBOOK OF A SNAPPED TREE. |
| 00:08 UTC | TSTM WND DMG | 1 Sw Bethalto | Madison, IL | LARGE PORTION OF HANGER ROOF AT ST. LOUIS REGIONAL AIRPORT (KALN) WAS PEELED OFF. VIA FACEBOOK WITH PICTURE. |
| 00:08 UTC | TSTM WND DMG | 1 W Bethalto | Madison, IL | TREE WITH ESTIMATED DIAMETER OF 2 FT SNAPPED. |
| 00:10 UTC | TSTM WND GST 55 | Freeburg | St. Clair, IL | |
| 00:10 UTC | TSTM WND GST 60 | Belleville | St. Clair, IL | |
| 00:11 UTC | HAIL 0.75 | 2 Ssw Mitchell | Madison, IL | REPORT FROM MPING: DIME (0.75 IN.). |
| 00:12 UTC | TSTM WND GST 60 | Belleville | St. Clair, IL | |
| 00:14 UTC | TSTM WND DMG | Fairview Heights | St. Clair, IL | VIA TWITTER WITH PICTURE INCLUDED: TREE FELL INTO HOUSE CAUSING DAMAGE TO INTERIOR OF HOME. |
| 00:15 UTC | TSTM WND DMG | 2 E Swansea | St. Clair, IL | HOME WITH ROOF DAMAGE. |
| 00:16 UTC | TSTM WND DMG | 2 W O'Fallon | St. Clair, IL | REPORT FROM MPING: 3-INCH TREE LIMBS BROKEN; POWER POLES BROKEN. |
| 00:20 UTC | TSTM WND DMG | 2 Ssw Saint Libory | St. Clair, IL | REPORT FROM MPING: 3-INCH TREE LIMBS BROKEN; POWER POLES BROKEN. |
| 00:25 UTC | TSTM WND DMG | 1 S Saint Jacob | Madison, IL | OUTBUILDING DESTROYED. ROOF BLOWN OFF. |
| 00:34 UTC | TSTM WND DMG | New Minden | Washington, IL | LARGE TREE BRANCH DOWN ONTO A POWER LINE. TIME ESTIMATED FROM RADAR. |
| 00:35 UTC | TSTM WND DMG | Trenton | Clinton, IL | FACEBOOK VIDEO SHOWS STORM DAMAGE OCCURRING IN TRENTON. TREES DOWN, FENCES BLOWN OVER, TRAMPOLINE TOSSED. TIME ESTIMATED FROM RADAR. |
| 00:37 UTC | TSTM WND DMG | New Minden | Washington, IL | LARGE TREE BRANCH DOWN ON POWER LINES. |
| 00:37 UTC | TORNADO | 3 Sw Highland | Madison, IL | HIGHLAND SADDLE CLUB DAMAGED. CALLER REPORTED DEBRIS EVERYWHERE AND NO POWER IN PORTIONS OF TOWN. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2023 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are
The other tornadoes of April 15, 2023
13 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| April 15 | 4:35 PM CDT | EF2 | Maries, MO | 6.9 | 880 | 5 | $2.0 million | |
| April 15 | 6:19 PM CDT | EF1 | Saint Louis, MO | 4.5 | 100 | |||
| April 15 | 6:24 PM CDT | EF0 | Jefferson, MO | 0.6 | 200 | |||
| April 15 | 6:30 PM CDT | EF1 | Jefferson, MO | 4.0 | 360 | 1 | ||
| April 15 | 6:30 PM CDT | EF1 | Bienville Parish, LA | 2.2 | 200 | $30,000 | ||
| April 15 | 6:34 PM CDT | EF1 | Monroe, IL | 19.6 | 100 | |||
| April 15 | 6:34 PM CDT | EF1 | Jefferson, MO | 0.9 | 150 | |||
| April 15 | 6:39 PM CDT | EF0 | Monroe, IL | 5.0 | 100 | |||
| April 15 | 6:43 PM CDT | Unrated | Monroe, IL | 0.3 | 25 | |||
| April 15 | 6:59 PM CDT | EF0 | Saint Clair, IL | 0.6 | 100 | |||
| April 15 | 7:01 PM CDT | Unrated | Madison, IL | 0.2 | 25 | |||
| April 15 | 7:03 PM CDT | EF0 | Saint Clair, IL | 1.1 | 90 | |||
| April 15 | 7:33 PM CDT | Unrated | Washington, IL | 0.2 | 50 |
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.