Tornadoes · United States · Kansas · 2018

EF0 tornado, Bestwall to Frankfort, Kansas, May 2, 2018

From Bestwall to Frankfort, this EF0 tornado ran 2.3 miles across Marshall County on May 2, 2018, touching down at 5:30 PM CDT and reaching 30 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 mphthis tornado

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

  2. EF186 to 110 mph

    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
EF0
Date
May 2, 2018
Touchdown
5:30 PM CDT (22:30 UTC)
Lifted
5:33 PM CDT (22:33 UTC)
On the ground
3 minutes
Path length
2.3 miles (3.7 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Marshall County
Touchdown point
39.583, -96.714
Lift-off point
39.596, -96.674
Record number
1805021630-01

The damage survey

5 damage points were recorded along this path by NWS TOP, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 85 mph.

  • old barn toppled by wind normally would be winds in excess of 85mph however terrible shape so EF0 range
  • another aluminum outbuilding blown down toward NE no other damage to home
  • cedars broken toward NE no other damage at property
  • 3 poles blown down toward NE and replaced intersection of 8th road and cyclone lane. No damage visible beyond this point.

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

A large cluster of t-storms developed during the afternoon of May 2 across central Kansas. The cluster evolved into a line or lines of storms that moved across northeast and east central Kansas during the afternoon and evening of May 2. Wind damage reports occurred in addition to a few tornado reports with the lines. At least 3 documented tornadoes occurred but all were short lived and relatively weak.

Short weak tornado along leading edge of outflow with bowing structure.

A small tornado appears to have occurred near and just ahead of the leading outflow of a line of storms. Damage to sheds, trees and outbuildings was noted especially just northeast of Frankfort.

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

The warnings

32 minutes of warning. NWS TOP issued a tornado warning for this county at 21:58 UTC, 32 minutes before the tornado touched down, in force until 22:45 UTC.

The county was under a tornado watch, issued at 17:43 UTC and running to 00:02 UTC.

Issued (UTC)ExpiredProductOffice
17:43 UTC00:02 UTCTornado WatchTOP
21:58 UTC22:45 UTCTornado WarningTOP
22:34 UTC23:15 UTCTornado WarningTOP
23:03 UTC23:35 UTCSevere Thunderstorm WarningTOP

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 20:16 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.

Topeka, KS (KFOE), 12:00Z

10.5 hours before the tornado, 112 km from the path. May 2, 2018.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 12:00Z on 2018-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 633 joules per kilogram, CIN -105, lifted condensation level 906 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, Topeka, KS at 12:00Z on 2018-05-02The 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 251 square meters per square second, 0 to 6 km bulk shear 39 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
633 J/kg
Mixed-layer CIN
-105 J/kg
Surface CAPE
1143 J/kg
Mixed-layer LCL
906 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
33 kt
0-1 km storm-relative helicity
251 m²/s²
0-3 km storm-relative helicity
228 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.1
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

The radar

The Topeka radar (KTWX), 77 km away, was scanning. The volume nearest the touchdown began at 22:27 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
21:45 UTCTSTM WND GST 601 N Clay CenterClay, KSSTRONG WINDS REPORTED ALONG THE GUST FRONT. POWER IS OUT IN THE AREA.
21:45 UTCHAIL 0.881 N Clay CenterClay, KSDIME TO NICKEL SIZE HAIL
21:58 UTCTSTM WND GST 613 Nnw Clay CenterClay, KS
22:20 UTCTSTM WND GST 50RileyRiley, KS
22:22 UTCTSTM WND GST 605 N LeonardvilleRiley, KS
22:30 UTCTORNADO6 Ssw Blue RapidsMarshall, KSCORRECTS PREVIOUS TORNADO REPORT FROM 6 SSW BLUE RAPIDS. A SMALL TORNADO OCCURRED IN MAINLY RURAL AREAS OF MARSHALL COUNTY. PATH APPROX. 2 MILES LONG EF0 WINDS TO AROUND 85 MPH.
22:33 UTCTSTM WND DMG6 Sse WatervilleMarshall, KSPOSSIBLE TORNADO DAMAGE TO A HOUSE - COINCIDENT WITH THE CIRCULATION. RADAR ESTIMATED TIME. DETAILS UNKNOWN AT THIS TIME.
22:35 UTCTSTM WND DMG4 S Blue RapidsMarshall, KSROOF DAMAGE TO A HOME.
22:40 UTCTSTM WND DMG1 Ene WatervilleMarshall, KSWINDOWS BLOWN OUT OF HOME AND SHED DESTROYED.
22:45 UTCTSTM WND GST 60N ManhattanRiley, KSLOCAL WEATHER STATION REPORT ON THE NORTH SIDE OF TOWN.
22:45 UTCTSTM WND GST 624 Nnw ManhattanRiley, KS
22:47 UTCTORNADO6 Wsw FrankfortMarshall, KSSMALL TORNADO DID SPORADIC DAMAGE ALONG A 8 MILE PATH TO NEAR FRANKFORT ON MAY 2. MAXIMUM DAMAGE PATH WIDTH APPROX. 60 YARDS.
22:47 UTCTORNADO7 Ssw Blue RapidsMarshall, KSA SMALL TORNADO OCCURRED IN MAINLY RURAL AREAS OF MARSHALL COUNTY. PATH APPROX. 8 MILES LONG EF0 WINDS TO AROUND 85 MPH.
22:48 UTCTSTM WND DMG2 Wsw FrankfortMarshall, KSLARGE TREE FELL ON A HOUSE.
22:48 UTCTSTM WND DMG3 W FrankfortMarshall, KSTREE LIMBS DOWN.
22:57 UTCTSTM WND DMG1 Ne FrankfortMarshall, KSROOF AND SIDING DAMAGE TO A HOME. SHED DESTROYED.
22:57 UTCTSTM WND DMG1 N FrankfortMarshall, KSROOF AND SIDING DAMAGE TO A HOME.
22:59 UTCTSTM WND DMG2 Nw VermillionMarshall, KSTREE LIMBS DOWN. POWER POLES DAMAGED. SIDING DAMAGE TO A HOME.
23:00 UTCTSTM WND DMG2 Se BeattieMarshall, KSTREE LIMBS DOWN.
23:09 UTCTSTM WND GST 704 Ssw BaileyvilleNemaha, KS
23:20 UTCTSTM WND GST 60Wsw CorningNemaha, KS

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

This ground now

The live radar over the trackEvery 2018 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

The other tornadoes of May 2, 2018

29 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 24:05 PM CDTEF0Ottawa, KS0.020
May 24:25 PM CDTEF0Greer, OK1.730
May 24:38 PM CDTUnratedKiowa, OK1.230
May 24:51 PM CDTEF0McPherson, KS2.075
May 25:46 PM CDTUnratedWilbarger, TX0.225
May 25:47 PM CDTEF0Marshall, KS7.760
May 26:10 PM CDTUnratedTillman, OK0.520
May 26:21 PM CDTUnratedTillman, OK0.420
May 26:26 PM CDTEF1Tillman, OK1.650$5,000
May 26:34 PM CDTEF1Tillman, OK5.5150$5,000
May 26:47 PM CDTEF2Tillman, OK4.1600$5,000
May 26:51 PM CDTEF0Butler, KS0.875
May 27:02 PM CDTUnratedTillman, OK3.550
May 27:07 PM CDTEF1Tillman, OK3.0250$4,000
May 27:18 PM CDTEF0Holt, MO4.025
May 27:45 PM CDTEF0Lyon, KS0.020
May 27:51 PM CDTEF0Coffey, KS0.025
May 27:55 PM CDTEF1Grady, OK10.0400$30,000
May 27:58 PM CDTEF1Grady, OK5.5100$20,000
May 28:04 PM CDTEF0Osage, KS0.025
May 28:05 PM CDTEF1Grady, OK0.425$10,000
May 28:42 PM CDTEF1Cleveland, OK8.0400$10,000
May 28:48 PM CDTEF1McClain, OK4.740$10,000
May 29:09 PM CDTEF1Johnson, KS4.725
May 29:19 PM CDTEF1Pottawatomie, OK0.850$2,000
May 29:22 PM CDTEF0Cass, MO0.010
May 29:24 PM CDTEF0Jackson, MO1.625
May 29:26 PM CDTEF0Jackson, MO1.325
May 210:39 PM CDTEF0Crockett, TX0.850$50,000

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.