EF1 tornado, Mill Spg to Patterson, Missouri, December 23, 2015

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

December 23, 2015

Touchdown

9:56 AM CST (15:56 UTC)

Lifted

10:00 AM CST (16:00 UTC)

On the ground

4 minutes

Path length

3.0 miles (4.7 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$5,000

County

Wayne County

Touchdown point

37.070, -90.773

Lift-off point

37.090, -90.726

Record number

1512230956-01

14 damage points were recorded along this path by NWS PAH and NWS SGF, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 105 mph.

• Few hundred trees snapped and uprooted along Highway Z within the Ozarks Scenic Riverways.
• Saw mill damaged...weak damage to roof. Saw mill claims he had a visual of the tornado.
• Tornado path through the community of Chilton. Convergent tree damage along with a school house that was destroyed.
• Couple dozen of trees snapped in this location.

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

Two fast-moving lines of strong to severe storms moved east across southeast Missouri, accompanied by strong winds and isolated tornadoes. A few bowing segments along the lines produced damaging winds. Conditions were favorable for severe storms. A negatively-tilted mid-level trough from the central high Plains to the Arklatex ejected northeast through the middle Mississippi Valley. At the surface, an area of low pressure over northeast Kansas moved to central Wisconsin. A trailing cold front surged eastward through the Mid-Mississippi and Lower Ohio Valleys. The storms were fed by a broadening and strengthening southwesterly low-level jet, which destabilized the atmosphere ahead of the storms. The presence of strong low-level and deep-layer wind shear enhanced the risk of wind damage and tornadoes.

Peak winds were estimated near 90 mph. Several tree trunks were snapped, and a few trees were uprooted. Several large tree branches were broken or snapped. The tornado occurred in heavily forested hilly terrain.

Peak winds were estimated near 105 mph. A couple dozen tree trunks were snapped, and several large tree branches were broken. Highway 34 was closed due to downed and uprooted trees. The tornado tracked along or just north of Highway 34, but it lifted before crossing U.S. Highway 67. The tornado tracked through forested areas and wetlands near the St. Francis River.

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

3 minutes of warning. NWS PAH issued a tornado warning for this county at 15:53 UTC, 3 minutes before the tornado touched down, in force until 16:30 UTC.

The county was under a tornado watch, issued at 15:13 UTC and running to 21:00 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 12:55 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), 175 km away, was scanning. The volume nearest the touchdown began at 15:56 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

30 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.