EF1 tornado, Buckhorn to Alliance, Missouri, May 25, 2011

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 25, 2011

Touchdown

5:26 PM CDT (22:26 UTC)

Lifted

5:33 PM CDT (22:33 UTC)

On the ground

7 minutes

Path length

13.0 miles (21.0 km)

Path width

250 yards (229 m)

Deaths

0

Injuries

0

Property damage

$30,000

Counties

Bollinger and Madison counties

Touchdown point

37.409, -90.168

Lift-off point

37.562, -90.025

Record number

1105251626-01

1 damage points were recorded along this path by NWS LSX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 83 mph.

• Old machine shed damaged. Collapsed of the east, north and western parts of building. Pieces of tin roofing materials were tossed 40 to 60 yards to the northeast. Width of damage path 30 yards.

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

Strong area of low pressure moved into the forecast area with a dry line out ahead of the main cold front. Storms fired up along and just ahead of the dry line beginning in the early afternoon hours. There were numerous reports of large hail with isolated damaging winds and tornadoes with this event.

Numerous strong to severe thunderstorms occurred in the warm sector of a low pressure system over central Missouri. The air mass in the warm sector was very unstable, with afternoon mixed-layer cape values in the 2500 to 4000 j/kg range. A 65 to 75 knot mid level jet was located across Arkansas, with the nose of the jet moving into western Kentucky. This feature enhanced the lift and strong deep-layer shear already in place, creating an environment very favorable for supercells and tornadoes. A 40 to 55 knot low level jet across eastern Arkansas moved into western Kentucky during the evening, resulting in a long-track strong tornado.

The tornado originated in Carter County then crossed into Wayne County (WFO Paducah's CWA) before crossing into Madison County about 3 miles southwest of Buckhorn and travelled to the northeast. In Madison County, numerous large trees were blown down before the tornado lifted and dissipated about a mile northwest of Buckhorn. The total path length for the tornado was 47.4 miles with a max width of 1200 yards and a max EF rating of EF3.

A tornado touched down just southwest of the intersection of U.S. 67 and State Highway N. As it travelled to the northeast and crossed U.S. 67 it blew down or uprooted numerous trees. The damage path width in this area was about 100 yards wide. The tornado continued to the northeast knocking down a lot of trees. As it crossed Madison County Road 303, about a mile southeast of the intersection with U.S. 67, the width of the tornado damage to the trees in this area was about a quarter of a mile wide. The tornado continued to the northeast for about a mile before lifting and dissipating.

Another tornado formed about a mile north of the one that had touched down near the intersection of U.S. 67 and State Highway N. It paralled the path of the other tornado lifting and dissipating about half a mile northeast of Madison County Road 303, about three quarters of a mile southeast of the intersection of U.S. 67 and Madison County Road 303. The damage was limited to numerous large trees blown down or uprooted along its path. The widest part of the damage path, about a third of a mile, was where the tornado crossed Madison County Road 303.

A tornado touched down about a mile and a half south of Marquand on State Highway DD. It travelled to the northeast for about two miles before moving into Bollinger County (WFO Paducah's CWA). It snapped off or uprooted numerous trees along its path in Madison County. At its widest, the tree damage was 200 yards wide. The total path length for the tornado was 13 miles with a max width of 250 yards and a max EF rating of EF1.

The tornado continued into Bollinger County from Madison County. Hundreds of trees were uprooted and snapped. Peak winds were estimated near 100 mph. The average path width was 200 yards.

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

41 minutes of warning. NWS LSX issued a tornado warning for this county at 21:45 UTC, 41 minutes before the tornado touched down, in force until 22:30 UTC.

The county was under a tornado watch, issued at 16:10 UTC and running to 00:27 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 High Risk, with a 0.30 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 19:39 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 Paducah radar (KPAH), 126 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.

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 2011 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

93 more were confirmed in the United States that day.

All 94 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.