EF1 tornado, Grayville to Somerville, Illinois, May 26, 2024

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

May 26, 2024

Touchdown

8:26 PM CDT (01:26 UTC)

Lifted

8:58 PM CDT (01:58 UTC)

On the ground

32 minutes

Path length

34.1 miles (54.8 km)

Path width

500 yards (457 m)

Deaths

0

Injuries

0

Property damage

$382,000

Crop damage

$5,000

Counties

White, Wabash and Gibson counties

Touchdown point

38.243, -87.999

Lift-off point

38.275, -87.373

Record number

2405261926-01

129 damage points were recorded along this path by NWS PAH, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 110 mph.

• Wheat field damaged with tracking patterns in it.
• Irrigation pivot, pointing to the east while the other one on the other side of the road was pointing to the west.
• Lots of tree branches down on this curve

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

The second major severe weather outbreak for the month occurred on the 26th for the Quad State region. On the synoptic scale, a shortwave trough centered in the middle of the country with a 60 kt mid-level jet moved across northern Arkansas. A weak surface low was moving into SE Missouri during the morning with a secondary low located further northwest. A warm frontal boundary was draped across our area. A bowing line progressed east across SE Missouri into W Kentucky and far S Illinois between 0500-1000CST, followed by a mostly sub-severe second line that exited the region by 1300CST. The environment recovered producing fuel for more severe storms, starting with supercells 1800-2100CST with a line of storms moving east-southeastward across the entire Quad State after 1900CST, crossing through by midnight. Across the Quad State, this event produced the record for most tornado track miles in a single day in office history, along with the second most warnings issued in a day (just behind the May 8, 2024 event). Widespread straight-line wind and tornado damage resulted in over 100,000 customers without power across the Quad State. ||For the morning, MLCAPE values at 0700CST were 1000-1500 J/kg in S Illinois. Effective bulk shear was 40-50 kts with STP of 1. Precipitable water was 1.5-1.75 in. The morning storms mostly missed just south of S Illinois with some street flooding in Johnston City. ||Heading into the evening, MLCAPE values at 1800CST were 2000-3500 J/kg in S Illinois. For S Illinois, effective bulk shear rose to 50 kts, with SRH around 150-250 m2/s2 and STP of 2-3.5. 0-1 km shear was 20 kts. Mid-level lapse rates were 7-7.5 C/km. DCAPE of 1200-1400 J/kg provided ample opportunity for downburst winds. ||Three tornadoes occurred in S Illinois. Two of these were with the late afternoon to early evening supercells. An EF-3 in the Lake of Egypt area of Johnson County debarked some trees, damaged several homes in the Eagle Point Bay subdivision, and injured one person. An EF-1 tornado in Johnson and Union Counties ahead of the approaching cold front tracked southeastward to Buncombe. The third tornado, an EF-1, was with the cold front in the Grayville area, tracking into Gibson County, IN. The supercells produced several hail reports, with a 2 inch hail report near the Williamson/Saline County border. Training heavy rain produced significant flash flooding for the second time in a month in Saline County, focused on Harrisburg with U.S. 45 flooded and at least one water rescue. Rainfall amounts in Southern Illinois were 1-4 inches, with the highest amounts in Alexander/Pulaski County and along a line from Williamson to Gallatin County. Numerous trees and power lines were damaged with the supercells and the frontal passage. Late evening power outages amounted to roughly a third of Williamson, Union, Johnson, and Alexander Counties.

The second major severe weather outbreak for the month occurred on the 26th for the Quad State region. On the synoptic scale, a shortwave trough centered in the middle of the country with a 60 kt mid-level jet moved across northern Arkansas. A weak surface low was moving into SE Missouri during the morning with a secondary low located further northwest. A warm frontal boundary was draped across our area. A bowing line progressed east across SE Missouri into W Kentucky and far S Illinois between 0500-1000CST, followed by a mostly sub-severe second line that exited the region by 1300CST. The environment recovered producing fuel for more severe storms, starting with supercells 1800-2100CST, just S/SW of SW Indiana, with a line of storms moving east-southeastward across the entire Quad State after 1900CST, crossing through by midnight. Across the Quad State, this event produced the record for most tornado track miles in a single day in office history, along with the second most warnings issued in a day (just behind the May 8, 2024 event). Widespread straight-line wind and tornado damage resulted in over 100,000 customers without power across the Quad State. ||SW Indiana was spared from severe weather impacts during the daytime rounds of storms. Heading into the evening, the most unstable environment was further southwest in SE Missouri and far W Kentucky, but MLCAPE values at 1800CST were 1500-2500 J/kg in SW Indiana. For SW Indiana, effective bulk shear rose to 50 kts, with SRH around 150 m2/s2 and STP of 2. 0-1 km shear was 20-25 kts. Mid-level lapse rates were 7-7.5 C/km. DCAPE of 1000-1200 J/kg provided ample opportunity for downburst winds. ||As the front swept through SW Indiana during the evening, several reports were made of straight-line wind damage, primarily in Gibson County. A long track EF-1 tornado also entered into Gibson County from the Grayville, IL area, then proceeded over 30 miles eastward damaging many trees, fields, and some homes and farm buildings, including on the north side of Fort Branch, before finally dissipating near Somerville.

An EF-1 tornado began in far northeastern White County south of Grayville. As it progressed eastward, the tornado damaged numerous trees and produced minor damage to homes in the area. A carport was damaged with damage to vehicles due to debris falling on them. The tornado crossed an offshoot of the Wabash River, reaching the portion of Gibson County, Indiana on Kingdom Island. Peak estimated winds with the White County segment, and the tornado as a whole, were 110 mph.

An EF-1 tornado (peak of EF-0 in this portion of Gibson County), which began in far northeastern White County south of Grayville, crossed into the Kingdom Island portion of Gibson County. The tornado produced minor tree damage before crossing into far southern Wabash County, IL. Peak estimated winds with this short Gibson County segment were 75 mph.

An EF-1 tornado (peak of EF-0 in Wabash County), which began in far northeastern White County south of Grayville, crossed into Wabash County from the Kingdom Island portion of Gibson County. The tornado produced minor tree damage before crossing the Wabash River into Gibson County, IN. Peak estimated winds with this short Wabash County segment were 75 mph.

An EF-1 tornado, which began south of Grayville, IL, crossed over the Wabash River through part of Gibson County and Wabash County, before re-entering Gibson County. The tornado tracked eastward through Fort Branch, Indiana. A roof was removed from a business near there and billboards were destroyed. Several fields suffered crop damage as well. Hundreds of trees were downed along this path. Some of the most significant damage along the path then occurred between Ft. Branch and Somerville near E Lake Charles Dr and S 175 E, where a garage was destroyed along with roof and siding damage to several homes. Several hardwood trees were snapped and twisted at trunk level. Additional significant damage occurred to several farm buildings on S 550 E with one collapsing. The tornado then ended as it crossed Somerville. Estimated peak winds for the Gibson County segment, and the tornado as a whole, were 110 mph. We greatly appreciate the assistance of Shawn Weber who provided both drone and ground survey assistance with this long track tornado.

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

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 23:59 UTC and running to 03:54 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 Enhanced Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 00:57 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.

The Evansville,IN radar (KVWX), 3 km away, was scanning. The volume nearest the touchdown began at 01:23 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 2024 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

69 more were confirmed in the United States that day.

All 70 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.