Tornadoes · United States · Pennsylvania · 2026

EF0 tornado, Lancaster County, Pennsylvania, August 20, 2026

This EF0 tornado ran 0.5 miles across Lancaster County on August 20, 2026, touching down at 4:38 PM EDT and reaching 125 yards wide. It killed nobody.

Preliminary. This is NWS CTP's damage survey, filed in the Damage Assessment Toolkit. The rating, the path and the casualties are the survey's and can change while it is revised. The Storm Prediction Center compiles the official record of 2026 from these surveys and publishes it in the spring of 2027; this page moves to that tornado's permanent address when it does.

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 survey

Rating, as surveyed
EF0, preliminary
Date
August 20, 2026
Touchdown
4:38 PM EDT (20:38 UTC)
Lifted
4:40 PM EDT (20:40 UTC)
On the ground
2 minutes
Path length
0.5 miles (0.8 km)
Path width
125 yards (114 m)
Deaths
0
Injuries
0
County
Lancaster County
Touchdown point
40.031, -76.388
Lift-off point
40.031, -76.378
Highest wind the damage implies
85 mph
Surveyed by
NWS CTP
Survey last edited
August 25, 2026
Record number
None yet. SPC numbers 2026 in the spring of 2027.

The damage survey

44 damage points were recorded along this path by NWS CTP, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 120 mph.

  • Window blown in, flag pole knocked over, fence damaged
  • Multiple large branches down
  • Multiple trees snapped near the tops.
  • Piece of roof thrown into trees

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

The warnings

9 minutes of warning. NWS CTP issued a tornado warning for this county at 20:29 UTC, 9 minutes before the tornado touched down, in force until 21:00 UTC.

The county was under a severe thunderstorm watch, issued at 18:31 UTC and running to 21:51 UTC.

Issued (UTC)ExpiredProductOffice
16:14 UTC21:56 UTCFlood WatchCTP
18:31 UTC21:51 UTCSevere Thunderstorm WatchCTP
20:12 UTC21:30 UTCSevere Thunderstorm WarningCTP
20:29 UTC21:00 UTCTornado WarningCTP
20:41 UTC23:45 UTCFlash Flood WarningCTP
20:47 UTC21:15 UTCTornado WarningCTP

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 19:55 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 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.

Washington/Dulle, VA (KIAD), 12:00Z

8.6 hours before the tornado, 149 km from the path. August 20, 2026.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2026-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 97 joules per kilogram, CIN -72, lifted condensation level 1192 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, Washington/Dulle, VA at 12:00Z on 2026-08-20The 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 115 square meters per square second, 0 to 6 km bulk shear 47 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
97 J/kg
Mixed-layer CIN
-72 J/kg
Surface CAPE
178 J/kg
Mixed-layer LCL
1192 m above ground
0-6 km bulk shear
47 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.0
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

Washington/Dulle, VA (KIAD), 00:00Z

3.4 hours after it, 149 km from the path. August 21, 2026.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2026-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 28 joules per kilogram, CIN -25, lifted condensation level 797 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, Washington/Dulle, VA at 00:00Z on 2026-08-21The 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 -93 square meters per square second, 0 to 6 km bulk shear 33 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
28 J/kg
Mixed-layer CIN
-25 J/kg
Surface CAPE
172 J/kg
Mixed-layer LCL
797 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
-93 m²/s²
0-3 km storm-relative helicity
-61 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1
0-3 km lapse rate
6.1 K/km

Open this sounding in Storm Lab

The surface observations

Lancaster (LNS), 12 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
18:40 UTC120° 6 kt1013.2
18:45 UTC120° 6 kt1013.2
18:50 UTC110° 5 kt1012.9
18:53 UTC7871110° 6 kt1012.9
18:55 UTC110° 6 kt1012.9
19:00 UTC110° 5 kt1012.5
19:05 UTC100° 5 kt1012.5
19:10 UTC80° 5 kt1012.5
19:15 UTC100° 5 kt1012.5
19:20 UTC100° 6 kt1012.2
19:25 UTC80° 4 kt1012.2
19:30 UTC80° 5 kt1012.2
19:34 UTC787280° 5 kt1012.2
19:35 UTC80° 5 kt1012.2
19:40 UTC70° 6 kt1012.2
19:45 UTC70° 5 kt1011.9
19:50 UTC70° 7 kt1011.5
19:53 UTC777270° 6 kt1011.5
19:55 UTC70° 6 kt1011.2
20:00 UTC60° 7 kt1010.8
20:05 UTC60° 8 kt1010.8
20:10 UTC50° 10 kt1010.2
20:15 UTC767240° 6 kt1010.2+RA BR
20:15 UTC40° 6 kt1010.2+RA BR
20:18 UTC76720° 0 kt1010.8+RA BR
20:20 UTC0° 0 kt1010.8RA BR
20:22 UTC757270° 3 kt1010.8VCTS RA BR
20:25 UTC60° 8 kt1010.5-RA BR
20:29 UTC757260° 11 kt1010.2TSRA BR
20:30 UTC 11 kt1010.2+RA BR
20:33 UTC747240° 15 kt201009.8+TSRA BR
20:35 UTC 211009.8+RA BR
20:40 UTC 251010.2RA BR
20:45 UTC 20 kt251011.2+RA BR
20:48 UTC73.471.6340° 20 kt311012.2+TSRA BR
20:50 UTC 19 kt1012.2+RA FG
20:53 UTC7271340° 21 kt321010.8+TSRA FG
20:55 UTC7170340° 26 kt321011.5+TSRA FG
20:55 UTC 311011.5+RA FG
21:00 UTC 341012.2+RA FG
21:05 UTC350° 23 kt1012.2+RA FG
21:07 UTC6766350° 23 kt401012.5TSRA BR
21:10 UTC6765340° 23 kt401012.9TSRA BR
21:10 UTC340° 23 kt311012.9RA BR
21:15 UTC 321012.9-RA
21:20 UTC10° 24 kt341012.5-RA
21:22 UTC686410° 21 kt371012.5VCTS -RA
21:25 UTC 381012.5-RA
21:30 UTC676310° 19 kt391012.9-RA
21:30 UTC 1012.9-RA
21:35 UTC 251012.9
21:40 UTC 241012.9
21:45 UTC 291012.9
21:50 UTC 1012.9
21:53 UTC676240° 18 kt301012.9
21:55 UTC 251012.9
22:00 UTC40° 21 kt281012.9
22:05 UTC 19 kt271013.2
22:10 UTC 261013.2
22:15 UTC30° 19 kt251013.2
22:20 UTC40° 18 kt251013.2
22:25 UTC 241013.5
22:30 UTC 17 kt221013.5
22:35 UTC 13 kt1013.9

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

The radar

The Sterling radar (KLWX), 151 km away, was scanning. The volume nearest the touchdown began at 20:40 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
19:49 UTCTSTM WND DMG2 S WrightsvilleYork, PADamage to buildings.
20:05 UTCTSTM WND DMG2 Ssw WrightsvilleYork, PARoof damage.
20:24 UTCTORNADO2 Sw WrightsvilleYork, PA*** 1 INJ *** An NWS Storm Survey confirmed an EF-2 tornado occurred in eastern York County, PA with a path length of 1.07 miles and a path width of 100 yards. The most significant damage occurred at Eastern York High Sc
20:28 UTCTSTM WND DMG1 E MillersvilleLancaster, PATree down blocking the road.
20:28 UTCTSTM WND DMG1 Nne HallamYork, PAThree trees, largest being 1 foot in diameter, snapped by thunderstorm winds.
20:30 UTCTSTM WND DMGColumbiaLancaster, PABuilding damage.
20:30 UTCTORNADO0 Sw ColumbiaLancaster, PAAn NWS Storm Survey confirmed an EF-1 tornado occurred in Columbia, PA with a path length of 1.47 miles and a path width of 100 yards. The tornado exhibited anomalous motion from northwest to southeast despite prevailing
20:33 UTCTSTM WND DMGColumbiaLancaster, PASevere building damage and walls collapsed.
20:33 UTCTSTM WND DMGColumbiaLancaster, PASevere building damage and collapsed walls.
20:37 UTCTORNADO2 Ese MountvilleLancaster, PAA brief EF-0 tornado occurred near Habecker Church Rd. It had a path length of 0.3 miles and path width of 75 yards. The estimated maximum wind speed was 65 mph.
20:38 UTCTSTM WND DMG2 E HallamYork, PAMultiple large oak trees down and aluminum siding debris in yard.
20:38 UTCTORNADO3 Nw MillersvilleLancaster, PAEF-0 Tornado, Max Estimated winds 85 mph, path length 0.49 miles, path width 125 yards.
20:42 UTCTSTM WND DMGColumbiaLancaster, PACollapsed shed and shingles blown off roofs.
20:53 UTCFLASH FLOOD2 Ne EphrataLancaster, PAWater rescue near the intersection of Garden Spot Road and Reading Road in Ephrata Township.
20:53 UTCFLASH FLOOD2 Ne EphrataLancaster, PAWater rescue on roadway.
20:57 UTCTSTM WND DMG3 Ssw Skyline ViewDauphin, PATree down blocking the right lane.
20:57 UTCFLASH FLOODManheimLancaster, PAWater rescue near the intersection of West High Street and South Penn Street.
21:00 UTCFLASH FLOODManheimLancaster, PAWater rescue.
21:06 UTCFLOOD3 W QuarryvilleLancaster, PAA couple of reports of flooded yards between Holtwood and Quarryville.
21:06 UTCFLOOD3 W QuarryvilleLancaster, PACorrects previous flood report from 3 W Quarryville. Reports of a couple of flooded yards and roads between Holtwood and Quarryville.
21:06 UTCTSTM WND DMG2 Se KenhorstBerks, PATree on Wires - Down on a residence. Time estimated by radar.
21:11 UTCTSTM WND DMG1 Nnw New MorganBerks, PAPhoto of a portion of a large tree broken in half along Moyer Road in Morgantown. Time estimated from radar.
21:16 UTCFLASH FLOOD2 W East PetersburgLancaster, PAStreet flooding reported.
21:20 UTCTSTM WND DMGHoney BrookChester, PATrees down and blocking route 322.
21:21 UTCFLOOD4 Nw Mount VernonLancaster, PAWater across roadway.
21:25 UTCTSTM WND DMGDowningtonChester, PABasketball hoop knocked over. Estimated max wind gusts up to 80 mph. Time estimated from radar.
21:25 UTCTSTM WND DMGGlenmooreChester, PATrees and wires down across Creek Road with wires arcing. Time estimated from radar.
21:28 UTCFLASH FLOOD3 E AkronLancaster, PAA couple of reports of water across roadways jus to the southeast of Akron.
21:33 UTCTSTM WND DMGEast Brandywine TwpChester, PAReport of power lines down in Guthriesville, East Brandywine Township. Time estimated from radar.
21:38 UTCTSTM WND DMGEast Nantmeal TwpChester, PATrees down.
21:40 UTCTSTM WND DMGDowningtonChester, PAReport and photos via social media of at least 2 trees down along East Pennsylvania Avenue in Downingtown. One felled tree appears to have crushed a shed. Time estimated from radar.
21:40 UTCTORNADOEast Caln TwpChester, PAA brief tornado occurred in East Caln Township. The first damage was noted just south of the intersection of East Lancaster Avenue and Quarry Road, where several small tree branches were broken. A path of more broken tre
21:41 UTCTSTM WND DMGWest GroveChester, PATrees down. some trees on wires.

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

This ground now

The live radar over the trackEvery 2026 tornado in PennsylvaniaEvery tornado in Pennsylvania since 1950Warnings in force in Pennsylvania nowThe forecast where you are

The other tornadoes of August 20, 2026

10 more have been surveyed in the United States that day, so far.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 204:09 PM EDTEF1Kent, DE3.2100
August 204:24 PM EDTEF2York, PA1.11001
August 204:30 PM EDTEF1Lancaster, PA3.0100
August 204:37 PM EDTEF0Lancaster, PA0.375
August 203:52 PM CDTUnratedMobile, AL3.10
August 205:40 PM EDTEF0Chester, PA0.230
August 205:41 PM EDTEF1Queen Anne's, MD0.570
August 205:54 PM EDTEF1Kent, DE1.360
August 206:02 PM EDTEF0Kent, DE0.6100
August 207:27 PM CDTEF0Hutchinson, SD0.125

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. A survey can be revised, so the rating, the path and the casualties can all still change.

Sources

NWS Damage Assessment Toolkit, the record the survey teams file from the damage, and NOAA Storm Prediction Center storm reports. Neither is the official database for 2026, which SPC publishes in the spring of 2027.