Tornadoes · United States · Pennsylvania · 2026
EF1 tornado, Lancaster County, Pennsylvania, August 20, 2026
This EF1 tornado ran 3.0 miles across Lancaster County on August 20, 2026, touching down at 4:30 PM EDT and reaching 100 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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- EF1, preliminary
- Date
- August 20, 2026
- Touchdown
- 4:30 PM EDT (20:30 UTC)
- Lifted
- 4:33 PM EDT (20:33 UTC)
- On the ground
- 3 minutes
- Path length
- 3.0 miles (4.8 km)
- Path width
- 100 yards (91 m)
- Deaths
- 0
- Injuries
- 0
- County
- Lancaster County
- Touchdown point
- 40.034, -76.501
- Lift-off point
- 40.006, -76.462
- Highest wind the damage implies
- 100 mph
- Surveyed by
- NWS CTP
- Survey last edited
- August 27, 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
1 minute of warning. NWS CTP issued a tornado warning for this county at 20:29 UTC, 1 minute 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) | Expired | Product | Office |
|---|---|---|---|
| 16:14 UTC | 21:56 UTC | Flood Watch | CTP |
| 18:31 UTC | 21:51 UTC | Severe Thunderstorm Watch | CTP |
| 20:12 UTC | 21:30 UTC | Severe Thunderstorm Warning | CTP |
| 20:29 UTC | 21:00 UTC | Tornado Warning | CTP |
| 20:41 UTC | 23:45 UTC | Flash Flood Warning | CTP |
| 20:47 UTC | 21:15 UTC | Tornado Warning | CTP |
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
8.5 hours before the tornado, 143 km from the path. August 20, 2026.
- 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
Washington/Dulle, VA (KIAD), 00:00Z
3.5 hours after it, 143 km from the path. August 21, 2026.
- 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
The surface observations
Lancaster (LNS), 19 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 18:40 UTC | 120° 6 kt | 1013.2 | ||||
| 18:45 UTC | 120° 6 kt | 1013.2 | ||||
| 18:50 UTC | 110° 5 kt | 1012.9 | ||||
| 18:53 UTC | 78 | 71 | 110° 6 kt | 1012.9 | ||
| 18:55 UTC | 110° 6 kt | 1012.9 | ||||
| 19:00 UTC | 110° 5 kt | 1012.5 | ||||
| 19:05 UTC | 100° 5 kt | 1012.5 | ||||
| 19:10 UTC | 80° 5 kt | 1012.5 | ||||
| 19:15 UTC | 100° 5 kt | 1012.5 | ||||
| 19:20 UTC | 100° 6 kt | 1012.2 | ||||
| 19:25 UTC | 80° 4 kt | 1012.2 | ||||
| 19:30 UTC | 80° 5 kt | 1012.2 | ||||
| 19:34 UTC | 78 | 72 | 80° 5 kt | 1012.2 | ||
| 19:35 UTC | 80° 5 kt | 1012.2 | ||||
| 19:40 UTC | 70° 6 kt | 1012.2 | ||||
| 19:45 UTC | 70° 5 kt | 1011.9 | ||||
| 19:50 UTC | 70° 7 kt | 1011.5 | ||||
| 19:53 UTC | 77 | 72 | 70° 6 kt | 1011.5 | ||
| 19:55 UTC | 70° 6 kt | 1011.2 | ||||
| 20:00 UTC | 60° 7 kt | 1010.8 | ||||
| 20:05 UTC | 60° 8 kt | 1010.8 | ||||
| 20:10 UTC | 50° 10 kt | 1010.2 | ||||
| 20:15 UTC | 76 | 72 | 40° 6 kt | 1010.2 | +RA BR | |
| 20:15 UTC | 40° 6 kt | 1010.2 | +RA BR | |||
| 20:18 UTC | 76 | 72 | 0° 0 kt | 1010.8 | +RA BR | |
| 20:20 UTC | 0° 0 kt | 1010.8 | RA BR | |||
| 20:22 UTC | 75 | 72 | 70° 3 kt | 1010.8 | VCTS RA BR | |
| 20:25 UTC | 60° 8 kt | 1010.5 | -RA BR | |||
| 20:29 UTC | 75 | 72 | 60° 11 kt | 1010.2 | TSRA BR | |
| 20:30 UTC | 11 kt | 1010.2 | +RA BR | |||
| 20:33 UTC | 74 | 72 | 40° 15 kt | 20 | 1009.8 | +TSRA BR |
| 20:35 UTC | 21 | 1009.8 | +RA BR | |||
| 20:40 UTC | 25 | 1010.2 | RA BR | |||
| 20:45 UTC | 20 kt | 25 | 1011.2 | +RA BR | ||
| 20:48 UTC | 73.4 | 71.6 | 340° 20 kt | 31 | 1012.2 | +TSRA BR |
| 20:50 UTC | 19 kt | 1012.2 | +RA FG | |||
| 20:53 UTC | 72 | 71 | 340° 21 kt | 32 | 1010.8 | +TSRA FG |
| 20:55 UTC | 71 | 70 | 340° 26 kt | 32 | 1011.5 | +TSRA FG |
| 20:55 UTC | 31 | 1011.5 | +RA FG | |||
| 21:00 UTC | 34 | 1012.2 | +RA FG | |||
| 21:05 UTC | 350° 23 kt | 1012.2 | +RA FG | |||
| 21:07 UTC | 67 | 66 | 350° 23 kt | 40 | 1012.5 | TSRA BR |
| 21:10 UTC | 67 | 65 | 340° 23 kt | 40 | 1012.9 | TSRA BR |
| 21:10 UTC | 340° 23 kt | 31 | 1012.9 | RA BR | ||
| 21:15 UTC | 32 | 1012.9 | -RA | |||
| 21:20 UTC | 10° 24 kt | 34 | 1012.5 | -RA | ||
| 21:22 UTC | 68 | 64 | 10° 21 kt | 37 | 1012.5 | VCTS -RA |
| 21:25 UTC | 38 | 1012.5 | -RA | |||
| 21:30 UTC | 67 | 63 | 10° 19 kt | 39 | 1012.9 | -RA |
| 21:30 UTC | 1012.9 | -RA | ||||
| 21:35 UTC | 25 | 1012.9 | ||||
| 21:40 UTC | 24 | 1012.9 | ||||
| 21:45 UTC | 29 | 1012.9 | ||||
| 21:50 UTC | 1012.9 | |||||
| 21:53 UTC | 67 | 62 | 40° 18 kt | 30 | 1012.9 | |
| 21:55 UTC | 25 | 1012.9 | ||||
| 22:00 UTC | 40° 21 kt | 28 | 1012.9 | |||
| 22:05 UTC | 19 kt | 27 | 1013.2 | |||
| 22:10 UTC | 26 | 1013.2 | ||||
| 22:15 UTC | 30° 19 kt | 25 | 1013.2 | |||
| 22:20 UTC | 40° 18 kt | 25 | 1013.2 | |||
| 22:25 UTC | 24 | 1013.5 | ||||
| 22:30 UTC | 17 kt | 22 | 1013.5 | |||
| 22:35 UTC | 13 kt | 1013.9 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Sterling radar (KLWX), 145 km away, was scanning. The volume nearest the touchdown began at 20:28 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 19:30 UTC | TSTM WND DMG | 3 N York Springs | Adams, PA | Downed trees reported in Latimore Township. Time estimated by radar. |
| 19:49 UTC | TSTM WND DMG | 2 S Wrightsville | York, PA | Damage to buildings. |
| 20:05 UTC | TSTM WND DMG | 2 Ssw Wrightsville | York, PA | Roof damage. |
| 20:24 UTC | TORNADO | 2 Sw Wrightsville | York, 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 UTC | TSTM WND DMG | 1 E Millersville | Lancaster, PA | Tree down blocking the road. |
| 20:28 UTC | TSTM WND DMG | 1 Nne Hallam | York, PA | Three trees, largest being 1 foot in diameter, snapped by thunderstorm winds. |
| 20:30 UTC | TSTM WND DMG | Columbia | Lancaster, PA | Building damage. |
| 20:30 UTC | TORNADO | 0 Sw Columbia | Lancaster, PA | An 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 UTC | TSTM WND DMG | Columbia | Lancaster, PA | Severe building damage and walls collapsed. |
| 20:33 UTC | TSTM WND DMG | Columbia | Lancaster, PA | Severe building damage and collapsed walls. |
| 20:37 UTC | TORNADO | 2 Ese Mountville | Lancaster, PA | A 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 UTC | TSTM WND DMG | 2 E Hallam | York, PA | Multiple large oak trees down and aluminum siding debris in yard. |
| 20:38 UTC | TORNADO | 3 Nw Millersville | Lancaster, PA | EF-0 Tornado, Max Estimated winds 85 mph, path length 0.49 miles, path width 125 yards. |
| 20:42 UTC | TSTM WND DMG | Columbia | Lancaster, PA | Collapsed shed and shingles blown off roofs. |
| 20:53 UTC | FLASH FLOOD | 2 Ne Ephrata | Lancaster, PA | Water rescue near the intersection of Garden Spot Road and Reading Road in Ephrata Township. |
| 20:53 UTC | FLASH FLOOD | 2 Ne Ephrata | Lancaster, PA | Water rescue on roadway. |
| 20:57 UTC | TSTM WND DMG | 3 Ssw Skyline View | Dauphin, PA | Tree down blocking the right lane. |
| 20:57 UTC | FLASH FLOOD | Manheim | Lancaster, PA | Water rescue near the intersection of West High Street and South Penn Street. |
| 21:00 UTC | FLASH FLOOD | Manheim | Lancaster, PA | Water rescue. |
| 21:06 UTC | FLOOD | 3 W Quarryville | Lancaster, PA | A couple of reports of flooded yards between Holtwood and Quarryville. |
| 21:06 UTC | FLOOD | 3 W Quarryville | Lancaster, PA | Corrects previous flood report from 3 W Quarryville. Reports of a couple of flooded yards and roads between Holtwood and Quarryville. |
| 21:06 UTC | TSTM WND DMG | 2 Se Kenhorst | Berks, PA | Tree on Wires - Down on a residence. Time estimated by radar. |
| 21:11 UTC | TSTM WND DMG | 1 Nnw New Morgan | Berks, PA | Photo of a portion of a large tree broken in half along Moyer Road in Morgantown. Time estimated from radar. |
| 21:16 UTC | FLASH FLOOD | 2 W East Petersburg | Lancaster, PA | Street flooding reported. |
| 21:20 UTC | TSTM WND DMG | Honey Brook | Chester, PA | Trees down and blocking route 322. |
| 21:21 UTC | FLOOD | 4 Nw Mount Vernon | Lancaster, PA | Water across roadway. |
| 21:25 UTC | TSTM WND DMG | Glenmoore | Chester, PA | Trees and wires down across Creek Road with wires arcing. Time estimated from radar. |
| 21:28 UTC | FLASH FLOOD | 3 E Akron | Lancaster, PA | A couple of reports of water across roadways jus to the southeast of Akron. |
| 21:33 UTC | TSTM WND DMG | East Brandywine Twp | Chester, PA | Report of power lines down in Guthriesville, East Brandywine Township. Time estimated from radar. |
| 21:41 UTC | TSTM WND DMG | West Grove | Chester, PA | Trees 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.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| August 20 | 4:09 PM EDT | EF1 | Kent, DE | 3.2 | 100 | |||
| August 20 | 4:24 PM EDT | EF2 | York, PA | 1.1 | 100 | 1 | ||
| August 20 | 4:37 PM EDT | EF0 | Lancaster, PA | 0.3 | 75 | |||
| August 20 | 4:38 PM EDT | EF0 | Lancaster, PA | 0.5 | 125 | |||
| August 20 | 3:52 PM CDT | Unrated | Mobile, AL | 3.1 | 0 | |||
| August 20 | 5:40 PM EDT | EF0 | Chester, PA | 0.2 | 30 | |||
| August 20 | 5:41 PM EDT | EF1 | Queen Anne's, MD | 0.5 | 70 | |||
| August 20 | 5:54 PM EDT | EF1 | Kent, DE | 1.3 | 60 | |||
| August 20 | 6:02 PM EDT | EF0 | Kent, DE | 0.6 | 100 | |||
| August 20 | 7:27 PM CDT | EF0 | Hutchinson, SD | 0.1 | 25 |
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.