Tornadoes · United States · Pennsylvania
Tornadoes in Montgomery County, Pennsylvania
20 tornadoes have crossed Montgomery County since 1950, 22nd of the 67 counties in Pennsylvania with a tornado on record, an average of one every 3.8 years. They have killed 4 people and injured 41. None was rated F4 or above. Before 1950, Grazulis's record of significant tornadoes has 5 more crossing the county, back to 1856.
The rating scale
Tracks are drawn in the color of the rating. The United States rated tornadoes on Ted Fujita’s F scale until 31 January 2007 and on the Enhanced Fujita scale after it. Both run from 0 to 5, and both rate the damage rather than measure the wind: the speeds are what that damage is taken to imply.
F0 / EF040 to 72 mph on the F scale, 65 to 85 mph on the EF scale
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F1 / EF173 to 112 mph on the F scale, 86 to 110 mph on the EF scale
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
F2 / EF2113 to 157 mph on the F scale, 111 to 135 mph on the EF scale
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.
F3 / EF3158 to 206 mph on the F scale, 136 to 165 mph on the EF scale
Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.
F4 / EF4207 to 260 mph on the F scale, 166 to 200 mph on the EF scale
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
F5 / EF5261 to 318 mph on the F scale, over 200 mph on the EF scale
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.
Now
- Tornadoes
- 20
- Deaths
- 4
- Injuries
- 41
- F4 and above
- 0
- Worst on record
- F3, July 27, 1994
The deadliest in Montgomery County
The strongest
- F3, Montgomery County, PennsylvaniaJuly 27, 1994
- F2, Berks and Montgomery counties, PennsylvaniaJune 24, 1960
- EF2, Montgomery County, PennsylvaniaSeptember 1, 2021
- F2, Montgomery County, PennsylvaniaAugust 13, 1956
- F2, Montgomery County, PennsylvaniaJune 8, 1961
- F2, Montgomery County, PennsylvaniaJune 24, 1960
Every year with a tornado
The 14 years of the 76 in the record with a tornado in Montgomery County. Each year links to every tornado in Pennsylvania that year.
Every tornado that crossed Montgomery County
20 tornadoes, newest first.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| September 1, 2021 | 5:35 PM EDT | EF2 | Montgomery | 8.3 | 400 | 1 | 2 | $5.0 million |
| August 18, 2021 | 12:25 AM EDT | EF1 | Montgomery | 8.8 | 140 | |||
| November 30, 2020 | 3:52 PM EST | EF0 | Montgomery | 0.9 | 100 | |||
| August 4, 2020 | 10:44 AM EDT | EF0 | Montgomery | 3.1 | 200 | |||
| September 23, 2003 | 7:20 AM EDT | F1 | Montgomery | 0.8 | 100 | $1.0 million | ||
| May 29, 1995 | 5:00 PM EDT | F1 | Montgomery | 1.5 | 50 | |||
| August 14, 1994 | 2:10 PM EDT | F1 | Montgomery | 1.0 | 100 | |||
| July 27, 1994 | 11:52 PM EDT | F3 | Montgomery | 2.0 | 100 | 3 | 25 | $5 million to $50 million |
| August 3, 1991 | 6:40 PM EDT | F1 | Montgomery | 5.0 | 100 | $500,000 to $5 million | ||
| November 16, 1989 | 11:00 AM EST | F0 | Montgomery | 5.2 | 50 | $5,000 to $50,000 | ||
| November 16, 1989 | 9:45 AM EST | F1 | Montgomery | 1.5 | 50 | 3 | $50,000 to $500,000 | |
| July 26, 1988 | 1:40 PM EDT | F0 | Montgomery | 1.5 | 50 | $50,000 to $500,000 | ||
| July 17, 1988 | 4:29 PM EDT | F1 | Montgomery | 1.8 | 67 | 1 | $50,000 to $500,000 | |
| May 20, 1982 | 8:00 PM EDT | F0 | Montgomery | 0.2 | 10 | 3 | $500 to $5,000 | |
| August 28, 1978 | 8:45 PM EDT | F1 | Montgomery | 0.5 | 67 | 1 | $5,000 to $50,000 | |
| July 4, 1966 | 4:45 PM GMT-4 | F0 | Montgomery | 2.0 | 20 | 5 | $50,000 to $500,000 | |
| June 8, 1961 | 6:05 PM GMT-4 | F2 | Montgomery | 1.0 | 200 | 1 | $5,000 to $50,000 | |
| June 24, 1960 | 6:40 PM GMT-4 | F2 | Montgomery | 0.8 | 27 | $50,000 to $500,000 | ||
| June 24, 1960 | 6:35 PM GMT-4 | F2 | Berks | 9.4 | 200 | $50,000 to $500,000 | ||
| August 13, 1956 | 6:00 PM GMT-4 | F2 | Montgomery | 1.3 | 333 | $5,000 to $50,000 |
Montgomery County before 1950
Before 1950 the record is Thomas P. Grazulis’s list of significant tornadoes: those rated F2 or stronger, and weaker ones that killed somebody. 5 of them crossed Montgomery County, killing 4. They are not in the figures above, which are SPC's from 1950.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 22, 1949 | 7:30 PM EST | F2 | SW Clayton/Palm/N Hosensack, PA | 9.6 | 200 | 2 | ||
| June 26, 1930 | 7:30 PM EST | F2 | Bridgeport, PA | 130 | ||||
| May 28, 1896 | 2:55 PM EST | F3 | S Ambler/Jarrettown/S Hatboro/Langhorne, PA/S Trenton/White Horse/Allentown, NJ | 35.1 | 200 | 4 | 15 | |
| August 3, 1885 | 11:30 AM EST | F2 | Lederachsville/Harleysville, PA | 3.5 | 100 | |||
| April 13, 1856 | 10:00 PM EST | Unrated | Kensington, Philidelphia, PA | 14.3 | 9 |
About the record before 1950
- Significant tornadoes only
- Grazulis listed tornadoes rated F2 or stronger, and weaker ones that killed somebody. Most tornadoes are weaker than F2, so the list holds a fraction of the tornadoes that happened.
- The early years are thin
- A tornado is on record only where somebody saw it and wrote it down. The count rises through the 1800s with settlement and newspapers, not with the weather.
- Rated from accounts
- Grazulis rated each tornado decades later from newspaper reports, Weather Bureau records and local histories, not from a damage survey.
- The tracks are reconstructed
- Tornado Archive drew each path through the places Grazulis names, most often as a straight line from the first to the last. A track can miss a town it hit, and a tornado with one named place is a point. The counties are today’s.
- A separate record
- SPC’s database, from 1950, counts every confirmed tornado of any strength. The two are kept apart on every page and never added together.
Nearby
Warnings in force in Montgomery CountyThe forecast for Montgomery CountyThe live radar over Montgomery CountyEvery county in Pennsylvania
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. Before 1950: Thomas P. Grazulis, Significant Tornadoes 1680-1991 and Significant Tornadoes 1880-1989, as digitized by Tornado Archive (Maas and others, 2024). Public domain. Counties assigned by this site from today’s NWS county lines.