EF0 tornado, Oak Grove to Blue Eye, Arkansas, December 31, 2010

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

December 31, 2010

Touchdown

7:48 AM CST (13:48 UTC)

Lifted

7:57 AM CST (13:57 UTC)

On the ground

9 minutes

Path length

4.3 miles (6.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$15,000

Counties

Carroll and Stone counties

Touchdown point

36.479, -93.440

Lift-off point

36.512, -93.396

Record number

1012310748-01

2 damage points were recorded along this path by NWS TSA, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 65 mph.

• End of tornado track in Carroll County, AR; tornado continued into Missouri, dissipating near the intersection of Highways 86 and 13

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

Unseasonably warm and moist air spread into northwestern Arkansas ahead of a cold front. Scattered thunderstorms developed in the late evening and early morning hours ahead of the cold front as a weak upper level disturbance passed through the region. Large hail and damaging wind gusts occurred with some of those storms. Another round of storms developed on the cold front over eastern Oklahoma as it pushed into the area. Weak to moderate instability combined with very strong low level wind shear created an environment that supported supercell thunderstorm structures. Several supercells developed resulting in large hail and damaging wind gusts in the hours just before and after sunrise on the 31st. One of these supercells produced a long-track, strong tornado that killed four people in and near the town of Cincinnati in Washington County. Debris was transported by the tornado into northern Benton County and was reported in Bella Vista and Pea Ridge. The Northwest Arkansas Regional Airport (XNA) was closed for three hours to remove the debris from the flight line. Another supercell produced a short-lived, weak tornado in Carroll County that moved into Missouri.

Between the evening of the 30th and the morning of the 31st, two separate lines of thunderstorms produced significant severe weather across southwest Missouri including damaging wind, large hail, and deadly tornadoes. The first round of storms lifted out of Arkansas late on the evening of the 30th and the second round moved out of western Kansas shortly before daybreak on the 31st.

A weak tornado damaged trees and barns. This tornado continued into Stone County, Missouri.

An EF-0 tornado touched down in Carrol County, Arkansas and moved into Stone County, Missouri. This tornado caused damage near an open field southwest of the intersection of Highway 86 and Highway 13 north of Blue Eye. The tornado knocked down several trees while destroying a carport at a residence. The tornado lifted as it was crossing Highway 13. The peak wind speeds were estimated at 65 miles per hour.

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

7 minutes of warning. NWS TSA issued a tornado warning for this county at 13:41 UTC, 7 minutes before the tornado touched down, in force until 14:00 UTC.

The county was under a tornado watch, issued at 13:33 UTC and running to 15:40 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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 12:53 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 Springfield radar (KSGF), 82 km away, was scanning. The volume nearest the touchdown began at 13:49 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 2010 tornado in ArkansasEvery tornado in Arkansas since 1950Warnings in force in Arkansas nowThe forecast where you are

28 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.