Tornadoes · United States · Iowa · 2020

EF1 tornado, Jesup to Fairbank, Iowa, March 28, 2020

From Jesup to Fairbank, this EF1 tornado ran 7.4 miles across Buchanan County on March 28, 2020, touching down at 6:15 PM CDT and reaching 50 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  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.

The record

Rating
EF1
Date
March 28, 2020
Touchdown
6:15 PM CDT (23:15 UTC)
Lifted
6:25 PM CDT (23:25 UTC)
On the ground
10 minutes
Path length
7.4 miles (11.9 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Buchanan County
Touchdown point
42.509, -92.081
Lift-off point
42.603, -92.014
Record number
2003281715-01

The damage survey

11 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 107 mph.

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

What the Weather Service recorded

A strong low pressure system tracked from southwest Iowa to north central Iowa Saturday afternoon. Storms developed, moved across a warm front, and four tornadoes touched down over eastern Iowa and northwest Illinois. A few other storms brought small hail and damaging wind to portions of the region Saturday night.

A tornado touched down north of Jesup, Iowa about 615 PM CDT, March 28th. The tornado moved northeast and caused damage to outbuildings and a barn, and uprooted trees at a farmstead. The tornado was on the ground for about 10 minutes, and traveled a little more than 7 miles. The tornado was rated EF-1, with maximum winds around 90 mph.

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

The warnings

2 minutes of warning. NWS DVN issued a tornado warning for this county at 23:13 UTC, 2 minutes before the tornado touched down, in force until 00:00 UTC.

The county was under a tornado watch, issued at 22:21 UTC and running to 00:39 UTC.

Issued (UTC)ExpiredProductOffice
22:21 UTC00:39 UTCTornado WatchDVN
23:03 UTC23:45 UTCSevere Thunderstorm WarningDVN
23:13 UTC00:00 UTCTornado WarningDVN
23:53 UTC00:21 UTCTornado WarningDVN

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 forecast that day

The Storm Prediction Center had this point in a Enhanced Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 20:06 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 air that afternoon

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.

Davenport, (KDVN), 12:00Z

11.3 hours before the tornado, 165 km from the path. March 28, 2020.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2020-03-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -75567, lifted condensation level 695 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 12:00Z on 2020-03-28The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity -128 square meters per square second, 0 to 6 km bulk shear 72 knots.1939587897117136Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-75567 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
695 m above ground
0-6 km bulk shear
72 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
-128 m²/s²
0-3 km storm-relative helicity
164 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.0 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 00:00Z

0.7 hours after it, 165 km from the path. March 29, 2020.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2020-03-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 504 joules per kilogram, CIN -27, lifted condensation level 963 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 00:00Z on 2020-03-29The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 480 square meters per square second, 0 to 6 km bulk shear 88 knots.1939587897117136156Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
504 J/kg
Mixed-layer CIN
-27 J/kg
Surface CAPE
915 J/kg
Mixed-layer LCL
963 m above ground
0-6 km bulk shear
88 kt
0-1 km bulk shear
44 kt
0-1 km storm-relative helicity
480 m²/s²
0-3 km storm-relative helicity
520 m²/s²
Significant tornado parameter
1.7
Supercell composite
9.3
0-3 km lapse rate
5.7 K/km

Open this sounding in Storm Lab

The surface observations

Independence (IIB), 14 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:15 UTC53.652.5110° 24 kt29994.9BR
21:35 UTC54.553.6120° 22 kt27994.6BR
21:55 UTC5755.6110° 24 kt28993.2
22:15 UTC57.655.8110° 20 kt25993.2
22:35 UTC58.556.5120° 22 kt27992.2
22:55 UTC5957120° 18 kt26991.5
23:15 UTC59.757.7120° 21 kt26990.5
23:35 UTC51.448.4230° 12 kt40991.9+RA
23:55 UTC54.550200° 19 kt26992.9-RA
00:15 UTC54.349.5210° 8 kt993.2
00:35 UTC54.748.7220° 7 kt993.2
00:55 UTC56.745230° 10 kt993.2

From the Iowa Environmental Mesonet's archive of airport observations.

The radar

The La Crosse radar (KARX), 157 km away, was scanning. The volume nearest the touchdown began at 23:16 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
20:43 UTCHAIL 0.25Strawberry PointClayton, IA.
20:43 UTCHAIL 0.25Strawberry PointClayton, IA
22:37 UTCTSTM WND DMG4 Se DikeGrundy, IAREPORT OF MACHINE SHED DESTROYED. TIME ESTIMATED FROM RADAR.
22:40 UTCTORNADO5 S HudsonBlack Hawk, IATORNADO ALSO CONFIRMED VIA SOCIAL MEDIA PHOTOS. LOCATION APPROXIMATE.
22:50 UTCTORNADO4 E HudsonBlack Hawk, IATRAINED SPOTTER REPORTED A GRAIN BIN AND OUTBUILDING DESTROYED. TIME ESTIMATED FROM RADAR.
23:15 UTCTORNADO2 Nnw JesupBuchanan, IAA TORNADO TOUCHED DOWN NORTH OF JESUP AND MOVED NORTHEAST CAUSING DAMAGE TO OUTBUILDINGS, A BARN, AND UPROOTED TREES AT A FARMSTEAD.
23:18 UTCTORNADO1 Ssw FairbankBuchanan, IAON GROUND NEAR BAXTER AVE AND V56 RD.
23:28 UTCHAIL 1.752 Se OttervilleBuchanan, IANOW SEEING PEA SIZE HAIL.
23:29 UTCTORNADO3 Nne LittletonBuchanan, IALARGE TORNADO ON THE GROUND DOING DAMAGE.
23:33 UTCFUNNEL CLOUD2 S OelweinFayette, IAFUNNEL CLOUD RAPIDLY DEVELOPING. POSSIBLE DEBRIS BUT UNSURE.
23:33 UTCTSTM WND DMG1 W OelweinFayette, IADAMAGE TO TREES AT RED GATE PARK ON WEST SIDE OF TOWN. POSSIBLE TORNADO.
23:33 UTCTORNADO1 W OelweinFayette, IACONFIRMED WITH VIDEO. DAMAGE TO APARTMENT BUILDINGS AND TREES IN RED GATE PARK.
23:33 UTCTORNADO1 W OelweinFayette, IACONFIRMED WITH VIDEO. DAMAGE TO APARTMENT BUILDINGS AND TREES IN RED GATE PARK. ENTIRE TORNADO WAS 630 TO 636 PM.
23:40 UTCTORNADO2 Se MaynardFayette, IACONFIRMED DAMAGE TO BARNS SOUTHEAST AND EAST OF MAYNARD. ENTIRE TORNADO WAS 640 TO 642 PM.
23:44 UTCTSTM WND DMG1 W OelweinFayette, IANUMEROUS TREES DOWN IN RED GATE PARK AREA. PROBABLE TORNADO BASED ON SPOTTER REPORTS.
23:50 UTCHAIL 0.5WadenaFayette, IA.
23:50 UTCHAIL 0.5WadenaFayette, IA
00:00 UTCFUNNEL CLOUD1 Ssw FayetteFayette, IAPOSSIBLE TORNADO. REPORTED ROPE FUNNEL APPROXIMATELY 5 TO 7 MILES NORTHEAST OF MAYNARD, IA APPROXIMATELY 7 PM.
00:15 UTCHAIL 1ElkaderClayton, IA.
00:15 UTCHAIL 1ElkaderClayton, IA

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2020 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

The other tornadoes of March 28, 2020

20 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 281:59 PM CDTEF1Adams, IA7.5115$125,000
March 284:18 PM CDTEF1Jackson, AR5.3200$200,000
March 284:26 PM CDTEF0Marshall, IA1.375
March 284:58 PM CDTEF3Jonesboro tornado, AR12.560022$300 million
March 285:25 PM CDTEF1Greene, AR3.0100$300,000
March 285:39 PM CDTUnratedKnox, IL0.110
March 285:39 PM CDTUnratedBlack Hawk, IA2.340
March 285:49 PM CDTEF0Black Hawk, IA2.1115$75,000
March 285:55 PM CDTUnratedBlack Hawk, IA0.320
March 286:30 PM CDTEF1Fayette, IA3.9140$165,000
March 286:40 PM CDTEF0Fayette, IA3.650$75,000
March 287:43 PM CDTUnratedHenry, IL1.110
March 287:58 PM CDTEF2Henderson, KY16.8500$500,000
March 288:01 PM CDTEF1Fulton, IL2.1100$100,000
March 288:18 PM CDTEF2Henderson, KY to IN5.15752$2.0 million
March 288:20 PM CDTEF1Whiteside, IL2.220
March 288:25 PM CDTEF1Dubuque, IA3.850
March 288:35 PM CDTEF1Grant, WI6.2120$180,000
March 288:58 PM CDTEF1Peoria, IL3.350$300,000
March 289:13 PM CDTEF1Ogle, IL7.0400

What this means

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.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.