EF0 tornado, Deerfield to Lime Spgs, Iowa, May 27, 2019

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

May 27, 2019

Touchdown

1:10 PM CDT (18:10 UTC)

Lifted

1:15 PM CDT (18:15 UTC)

On the ground

5 minutes

Path length

4.1 miles (6.5 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

Property damage

$35,000

Counties

Chickasaw and Howard counties

Touchdown point

43.169, -92.531

Lift-off point

43.221, -92.492

Record number

1905271210-01

15 damage points were recorded along this path by NWS ARX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 109 mph.

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

As an area of low pressure moved across the Upper Midwest, thunderstorms developed during the afternoon of Memorial Day (May 27th) across portions of northeast Iowa. These storms quickly became severe and produced tornadoes across Floyd, Chickasaw and Howard Counties. The first tornado developed near Charles City (Floyd County) and was on the ground for about 7 miles, extensively damaging some buildings at the Floyd County fairgrounds along damaging three houses severe enough to make them inhabitable. Another tornado moved across rural portions of Howard County for 12 miles and damaged a wind turbine and cattle barns. Two other weaker tornadoes also touched down across northwest Chickasaw County and northern Howard County very close to the Minnesota state line.

A tornado touched down across northwest Chickasaw County southwest of Alta Vista. The tornado traveled north-northeast across rural parts of the county before passing into Howard County southwest of Elma. This was spotted by area fire departments.

A tornado entered into Howard County southwest of Elma as it moved north-northeast and then dissipated after crossing Dale Avenue. Farm buildings were damaged just north of the Chickasaw County line. This was witnessed by area fire departments serving as spotters.

A tornado formed over rural Howard County south of Saratoga and then traveled north-northeast before dissipating just before entering Lime Springs. The tornado struck and destroyed a wind turbine north of State Highway 9 and also destroyed a large farm building along Lilac Avenue.

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

3 minutes of warning. NWS ARX issued a tornado warning for this county at 18:07 UTC, 3 minutes before the tornado touched down, in force until 18:24 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 Marginal Risk. The outlook in force was issued at 16:22 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 La Crosse radar (KARX), 127 km away, was scanning. The volume nearest the touchdown began at 18:11 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 2019 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

62 more were confirmed in the United States that day.

All 63 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.