Tornadoes · United States · Colorado · 2020

EF0 tornado, Amherst, Colorado, July 8, 2020

This EF0 tornado ran 0.0 miles across Phillips County on July 8, 2020, touching down at 6:04 PM MDT 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 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.

The record

Rating
EF0
Date
July 8, 2020
Touchdown
6:04 PM MDT (00:04 UTC)
Lifted
6:05 PM MDT (00:05 UTC)
On the ground
1 minutes
Path length
0.0 miles (0.0 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Phillips County
Touchdown point
40.851, -102.132
Lift-off point
40.851, -102.132
Record number
2007081804-02

The damage survey

1 damage points were recorded along this path by NWS LBF, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 70 mph.

  • Weak landspout tornado, no damage reported.

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

Severe thunderstorms produced several brief landspout tornadoes in Sedgwick County. One unoccupied building sustained some damage while the rest touched down in open fields. In addition, thunderstorm wind gusts up to 70 mph were measured.

A tornado touched down briefly near the intersection of CO 16 and CO 55. No damage was observed.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

Issued (UTC)ExpiredProductOffice
23:20 UTC00:00 UTCSevere Thunderstorm WarningBOU
00:00 UTC00:45 UTCSevere Thunderstorm WarningBOU
00:17 UTC00:45 UTCTornado WarningBOU
00:42 UTC01:03 UTCSevere Thunderstorm WarningBOU

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 Slight Risk. The outlook in force was issued at 19:57 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.

N. Platte/Lee Bi, NE (KLBF), 00:00Z

0.1 hours before the tornado, 132 km from the path. July 9, 2020.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 00:00Z on 2020-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2624 joules per kilogram, CIN -22, lifted condensation level 2346 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, N. Platte/Lee Bi, NE at 00:00Z on 2020-07-09The 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 8 square meters per square second, 0 to 6 km bulk shear 25 knots.193958Sfc1 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
2624 J/kg
Mixed-layer CIN
-22 J/kg
Surface CAPE
4330 J/kg
Mixed-layer LCL
2346 m above ground
0-6 km bulk shear
25 kt
0-1 km bulk shear
12 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.6
0-3 km lapse rate
8.8 K/km

Open this sounding in Storm Lab

N. Platte/Lee Bi, NE (KLBF), 12:00Z

11.9 hours after it, 132 km from the path. July 9, 2020.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2020-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 207 joules per kilogram, CIN -563, lifted condensation level 1906 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, N. Platte/Lee Bi, NE at 12:00Z on 2020-07-09The 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 58 square meters per square second, 0 to 6 km bulk shear 27 knots.193958Sfc1 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
207 J/kg
Mixed-layer CIN
-563 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1906 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
58 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1
0-3 km lapse rate
2.0 K/km

Open this sounding in Storm Lab

The radar

The Goodland radar (KGLD), 169 km away, was scanning. The volume nearest the touchdown began at 00:04 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
23:50 UTCTORNADO12 Ne Sixteen-Mile CornSedgwick, COPH315 REPORTED A TOUCHDOWN APPROXIMATELY 20 NE OF HOLYOKE.
00:00 UTCTORNADO10 Nne AmherstSedgwick, COS131 REPORTED A TOUCHDOWN AT THE INTERSECTION OF CO 12 AND CO 53.
00:05 UTCTORNADO10 Se SedgwickSedgwick, COSEDGWICK EM REPORTED A TOUCHDOWN NEAR THE INTERSECTION OF CO 18 AND HIGHWAY 385 BY NAWAS.
00:05 UTCTORNADO20 Se SedgwickPhillips, COSEDGWICK EM REPORTED A TOUCHDOWN NEAR THE INTERSECTION OF CO 16 AND CO 55.
00:05 UTCTORNADO20 Se SedgwickPhillips, COSEDGWICK EM REPORTED A TOUCHDOWN NEAR THE INTERSECTION OF CO 16 AND CO 57.
00:11 UTCTSTM WND GST 632 Se JulesburgSedgwick, COCO034 AT 1812 MDT.
00:11 UTCTORNADO7 Ne Sixteen-Mile CorneSedgwick, COMULTIPLE SPOTTER REPORTS OF UP TO THREE LANDSPOUT TORNADOES.
00:20 UTCTORNADO12 Se JulesburgSedgwick, COSEDGWICK EM REPORTED DAMAGE TO AN UNOCCUPIED BUILDING NEAR THE INTERSECTION OF CO 16 AND CO 55.
00:29 UTCTSTM WND GST 655 N Sixteen-Mile CornerSedgwick, CO

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 ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of July 8, 2020

17 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 84:20 AM CDTEF1Wilkin, MN12.4200$550,000
July 84:38 AM CDTEF1Otter Tail, MN18.7250$750,000
July 85:10 AM CDTEF2Otter Tail, MN2.0300$200,000
July 84:04 PM CDTUnratedWhiteside, IL0.310
July 85:08 PM CDTEF4Ashby–Dalton tornado, MN8.965012$1.6 million
July 86:32 PM CDTEF0Otter Tail, MN0.220
July 85:49 PM MDTEF0Sedgwick, CO0.050
July 85:50 PM MDTUnratedPerkins, NE0.110
July 85:55 PM MDTUnratedPerkins, NE0.110
July 85:59 PM MDTEF0Sedgwick, CO0.050
July 86:01 PM MDTUnratedPerkins, NE0.110
July 86:04 PM MDTEF0Sedgwick, CO0.050
July 86:10 PM MDTEF0Sedgwick, CO0.050
July 87:15 PM CDTEF0Crow Wing, MN7.450$10,000
July 86:19 PM MDTEF0Sedgwick, CO0.050
July 87:55 PM CDTUnratedThomas, NE0.110
July 811:29 PM CDTEF0Merrick, NE4.2130$200,000

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.