Tornadoes · United States · Colorado · 2019

EF0 tornado, Denver Front Range A, Colorado, May 26, 2019

This EF0 tornado ran 0.0 miles across Adams County on May 26, 2019, touching down at 5:37 PM MDT and reaching 25 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
May 26, 2019
Touchdown
5:37 PM MDT (23:37 UTC)
Path length
0.0 miles (0.0 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
County
Adams County
Touchdown point
39.770, -104.560
Lift-off point
39.770, -104.560
Record number
1905261737-01

What the Weather Service recorded

Severe thunderstorms broke out across parts of Adams, Arapahoe, Denver, Lincoln, Morgan and Weld counties during the late afternoon and early evening. In Weld County, very large hail from 1 1/2 to 3 inches in diameter was reported along with wind gusts to 60 mph. Elsewhere, the hail size ranged from 3/4 to 1 1/4 inches in diameter. A total of five tornadoes touched down in open country with no damage reported. At Denver International Airport, up to 3 inches of hail accumulated on runway surfaces. Consequently, dozens of flights were either delayed or cancelled so runways could be cleared and airplanes inspected for hail damage.

A tornado touched down briefly in an open field. No damage was reported.

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

The warnings

7 minutes of warning. NWS BOU issued a tornado warning for this county at 23:30 UTC, 7 minutes before the tornado touched down, in force until 23:45 UTC.

The county was under a tornado watch, issued at 21:46 UTC and running to 01:42 UTC.

Issued (UTC)ExpiredProductOffice
21:46 UTC01:42 UTCTornado WatchBOU
21:51 UTC21:59 UTCSevere Thunderstorm WarningBOU
22:34 UTC23:00 UTCTornado WarningBOU
23:23 UTC23:55 UTCSevere Thunderstorm WarningBOU
23:30 UTC23:45 UTCTornado 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, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:56 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.

Denver, CO (KDEN), 12:00Z

11.6 hours before the tornado, 114 km from the path. May 26, 2019.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2019-05-26Temperature 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 -47154, lifted condensation level 1575 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 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, Denver, CO at 12:00Z on 2019-05-26The 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 46 square meters per square second, 0 to 6 km bulk shear 42 knots.1939587897Sfc1 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
-47154 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1575 m above ground
0-6 km bulk shear
42 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.6 K/km

Open this sounding in Storm Lab

Denver, CO (KDEN), 00:00Z

0.4 hours after it, 114 km from the path. May 27, 2019.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 00:00Z on 2019-05-27Temperature 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 -208, lifted condensation level 2004 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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, Denver, CO at 00:00Z on 2019-05-27The 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 -191 square meters per square second, 0 to 6 km bulk shear 52 knots.1939587897Sfc1 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
-208 J/kg
Surface CAPE
992 J/kg
Mixed-layer LCL
2004 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
14 kt
0-1 km storm-relative helicity
-191 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.9
0-3 km lapse rate
6.8 K/km

Open this sounding in Storm Lab

The surface observations

Front Range (FTG), 2 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:51 UTC75.248.2130° 16 kt201009.5
22:57 UTC62.653.6350° 8 kt1008.8
23:51 UTC5955.4310° 12 kt231008.5-TSRA
00:51 UTC57.253.650° 10 kt1008.8

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

The radar

The Denver radar (KFTG), 2 km away, was scanning. The volume nearest the touchdown began at 23:38 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
21:52 UTCHAIL 0.88Fort LuptonWeld, CO
22:13 UTCHAIL 1.254 N HudsonWeld, CO
22:20 UTCHAIL 1.254 S Barr LakeAdams, CO
22:27 UTCHAIL 1.55 Sse Milton ReservoirWeld, CO
22:32 UTCTSTM WND GST 603 Wnw KeenesburgWeld, CO
22:38 UTCTORNADO1 Nw KeenesburgWeld, COBRIEF TOUCHDOWN IN OPEN FIELD. NO DAMAGE REPORTED.
22:53 UTCTORNADO3 Nw RoggenWeld, COCORRECTS PREVIOUS TORNADO REPORT FROM 6 NW ROGGEN. BRIEF TOUCHDOWN, THEN BECAME QUICKLY RAIN WRAPPED AND NOT VISIBLE. NO DAMAGE REPORTED.
23:05 UTCHAIL 13 Nne Cherry Hills VillDenver, CO
23:10 UTCHAIL 13 W AuroraArapahoe, CO
23:37 UTCTORNADO2 Ne WatkinsAdams, COBRIEF TOUCHDOWN APPROXIMATELY 1 MILE SOUTH OF FRONT RANGE AIRPORT. NO DAMAGE REPORTED.
23:38 UTCTORNADO6 Nw RoggenWeld, COBRIEF TOUCHDOWN, THEN BECAME QUICKLY RAIN WRAPPED AND NOT VISIBLE. NO DAMAGE REPORTED.
23:51 UTCHAIL 0.75Denver Intl AirportDenver, CODENVER TOWER REPORTED 3 INCHES OF ACCUMULATED HAIL ON AIRPORT OPERATING SURFACES.

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

This ground now

The live radar over the trackEvery 2019 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of May 26, 2019

37 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 261:15 AM CDTEF0McIntosh, OK0.275
May 261:23 AM CDTEF1Champaign, IL0.9250
May 261:27 AM CDTEF1Champaign, IL0.8250
May 261:35 AM CDTEF1Champaign, IL1.0250
May 261:44 AM CDTEF0Mayes, OK3.2300
May 262:30 AM CDTEF0Washington, AR1.5100
May 261:57 PM MDTEF0Bingham, ID1.8100$1,000
May 262:38 PM MDTUnratedProwers, CO0.320
May 262:54 PM MDTUnratedBent, CO0.320
May 264:36 PM CDTEF0Thomas, KS1.0100$42,000
May 264:10 PM MDTUnratedKiowa, CO0.320
May 264:38 PM MDTEF0Weld, CO0.025
May 264:53 PM MDTEF0Weld, CO0.025
May 264:55 PM MDTEF0Union, NM21.775
May 265:27 PM MDTEF0Weld, CO0.025
May 265:50 PM MDTEF0Union, NM2.650
May 265:58 PM MDTEF0Lincoln, CO0.050
May 266:04 PM MDTEF0Chaves, NM2.450
May 267:21 PM CDTEF1Franklin, NE1.9500$125,000
May 266:25 PM MDTEF0Roosevelt, NM0.850
May 267:25 PM CDTEF0Oldham, TX0.350
May 268:02 PM CDTEF0Hartley, TX2.050
May 268:14 PM CDTEF0Hartley, TX5.275
May 267:20 PM MDTEF2Roosevelt, NM9.5200$2.0 million
May 267:57 PM MDTEF0Roosevelt, NM2.150
May 269:11 PM CDTEF0Bailey, TX5.050$50,000
May 269:22 PM CDTEF0Washington, KS0.150
May 269:56 PM CDTEF2Lamb, TX8.0100$150,000
May 2610:26 PM CDTEF0Castro, TX12.8100$100,000
May 2610:49 PM CDTEF1Gray, KS0.725$60,000
May 2610:51 PM CDTEF1Ford, KS1.925
May 2610:52 PM CDTEF1Ford, KS1.825
May 2611:07 PM CDTEF1Ford, KS3.150
May 2611:14 PM CDTEF0Hodgeman, KS1.725
May 2611:28 PM CDTEF1Hodgeman, KS1.325$60,000
May 2612:00 AM CDTEF1Pratt, KS8.9100
May 2612:25 AM CDTEF0Oldham, TX1.550

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.