EF0 tornado, West Line to Harrisonville Arpt, Missouri, September 18, 2015

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.

Rating

EF0

Date

September 18, 2015

Touchdown

8:32 PM CDT (01:32 UTC)

Lifted

8:35 PM CDT (01:35 UTC)

On the ground

3 minutes

Path length

2.3 miles (3.7 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

County

Cass County

Touchdown point

38.610, -94.359

Lift-off point

38.608, -94.317

Record number

1509181932-01

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

• At Midway High School, an outbuilding for ticket sales as well as numerous metal bleachers destroyed.
• roofing damage at Midway High School
• Scoreboard bent over at Cass Midway High School
• point should be moved 200 yards south of highway 2.

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

After a generally rainy and cloudy, enough sunshine broke through late in the afternoon to enable a supercell thunderstorm to develop, along a southeastward advancing cold front. The supercell produced several tornadoes with a rating up to an EF-1. The storm developed just prior to the start of Friday night football games. Officials at one game evacuated the stands prior to a direct hit on the stadium. They credited the tornado warnings with providing enough lead time to get people inside and into safety before the tornado hit.

A NWS storm survey found that the tornado formed east of West Line along Missouri Highway 2 and traveled a few degrees south of east. The storm struck Cass-Midway High School were a football game was about to be played. However due to advanced warning, all attendees, about 250 people, were placed into shelter about 10 minutes prior to the tornado making a direct hit on the stadium. No injuries were reported despite extensive damage to the stands and scoreboard.

Live footage from a broadcast media helicopter as well as storm chaser reports show a weak and intermittent tornado touched down south of Harrisonville, east of I-49, causing minor damage to a Walmart distribution center.

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. One was issued for the county at another hour that day.

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 Marginal Risk. The outlook in force was issued at 01:00 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 Pleasant Hill radar (KEAX), 23 km away, was scanning. The volume nearest the touchdown began at 01:31 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.

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 2015 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

3 more were confirmed in the United States that day.

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.