Mercersburg, PA Natural Disasters and Weather Extremes
The chance of earthquake damage in Mercersburg is about the same as Pennsylvania average and is much lower than the national average. The risk of tornado damage in Mercersburg is lower than Pennsylvania average and is lower than the national average.
Earthquake Index, #1271
| Mercersburg, PA | 0.03 |
| Pennsylvania | 0.17 |
| U.S. | 1.81 |
The earthquake index value is calculated based on historical earthquake events data using USA.com algorithms. It is an indicator of the earthquake level in a region. A higher earthquake index value means a higher chance of an earthquake.
Volcano Index, #1
| Mercersburg, PA | 0.0000 |
| Pennsylvania | 0.0000 |
| U.S. | 0.0023 |
The volcano index value is calculated based on the currently known volcanoes using USA.com algorithms. It is an indicator of the possibility of a region being affected by a possible volcano eruption. A higher volcano index value means a higher chance of being affected.
Tornado Index, #1976
| Mercersburg, PA | 75.13 |
| Pennsylvania | 109.77 |
| U.S. | 136.45 |
The tornado index value is calculated based on historical tornado events data using USA.com algorithms. It is an indicator of the tornado level in a region. A higher tornado index value means a higher chance of tornado events.
Other Weather Extremes Events
A total of 3,195 other weather extremes events within 50 miles of Mercersburg, PA were recorded from 1950 to 2010. The following is a break down of these events:
| Type | Count | Type | Count | Type | Count | Type | Count | Type | Count |
| Avalanche: | 0 | Blizzard: | 3 | Cold: | 27 | Dense Fog: | 16 | Drought: | 17 |
| Dust Storm: | 0 | Flood: | 491 | Hail: | 483 | Heat: | 31 | Heavy Snow: | 49 |
| High Surf: | 0 | Hurricane: | 0 | Ice Storm: | 16 | Landslide: | 0 | Strong Wind: | 62 |
| Thunderstorm Winds: | 1,668 | Tropical Storm: | 2 | Wildfire: | 7 | Winter Storm: | 58 | Winter Weather: | 47 |
| Other: | 218 | ||||||||
Volcanos Nearby
No volcano is found in or near Mercersburg, PA.
Historical Earthquake Events
No historical earthquake events that had recorded magnitudes of 3.5 or above found in or near Mercersburg, PA.
No historical earthquake events found in or near Mercersburg, PA.
Historical Tornado Events
A total of 19 historical tornado events that had recorded magnitude of 2 or above found in or near Mercersburg, PA.
| Distance (miles) | Date | Magnitude | Start Lat/Log | End Lat/Log | Length | Width | Fatalities | Injuries | Property Damage | Crop Damage | Affected County |
| 25.4 | 1961-04-16 | 3 | 40°03'N / 77°31'W | 0 | 0 | 250K | 0 | Cumberland | |||
| 32.3 | 2004-09-17 | 2 | 39°22'N / 78°02'W | 39°23'N / 78°02'W | 2.00 Miles | 100 Yards | 0 | 6 | 25K | 0 | Berkeley |
| Brief Description: A tornado touched down in Darkesville in southern Berkeley County. The F2 tornado produced extensive structural damage to homes and businesses in the area. The storm traveled north and toppled tractor trailers and vehicles on Interstate-81. At least 6 people were injured from the automobile accidents. | |||||||||||
| 33.9 | 1996-07-19 | 2 | 39°23'N / 77°42'W | 39°21'N / 77°42'W | 2.00 Miles | 125 Yards | 0 | 0 | 400K | 75K | Washington |
| Brief Description: A moderate tornado (F2) tracked between two mountain ridges in extreme southern Washington Co, knocking down hundreds of trees, including several onto homes which caused substantial damage. At least one barn was completely destroyed in Yarrowsburg. The storm attained maximum strength just south of town (where the trees, including numerous hardwoods, were flattened). The tornado weakened considerably before dissipating along the eastern ridge. Structural and vehicle damage, though not as prevalent as the tree damage, included the following: Portions of roofs from two barns were blown off; minor residential damage, including shattered windows, unhinged shingles, and torn off trim/gutters. Some gravestones were overturned by the winds, and several power lines were knocked down. Several vehicles and vehicle windows were damaged. | |||||||||||
| 33.9 | 2004-09-17 | 2 | 39°24'N / 77°33'W | 39°24'N / 77°39'W | 3.00 Miles | 200 Yards | 0 | 0 | 5K | 0 | Frederick |
| Brief Description: An F2 tornado touched down in far northwest Frederick County, on the northwest edge of Catoctin Mountain Park. A thickly forested stand of hardwood trees was snapped off above the bases. | |||||||||||
| 35.3 | 1976-03-21 | 2 | 39°56'N / 77°15'W | 1.00 Mile | 50 Yards | 0 | 0 | 25K | 0 | Adams | |
| 36.3 | 1983-05-22 | 3 | 39°42'N / 77°15'W | 39°42'N / 77°14'W | 1.00 Mile | 37 Yards | 0 | 0 | 25K | 0 | Frederick |
| 37.4 | 1983-05-22 | 3 | 39°42'N / 77°14'W | 39°43'N / 77°12'W | 1.00 Mile | 37 Yards | 0 | 0 | 25K | 0 | Carroll |
| 37.8 | 1989-11-16 | 2 | 39°15'N / 77°47'W | 39°20'N / 77°48'W | 9.00 Miles | 50 Yards | 0 | 3 | 250K | 0 | Jefferson |
| 38.9 | 1961-07-13 | 2 | 39°19'N / 78°12'W | 0 | 1 | 3K | 0 | Frederick | |||
| 41.9 | 1978-07-31 | 2 | 39°24'N / 77°21'W | 1.50 Miles | 100 Yards | 0 | 0 | 25K | 0 | Frederick | |
| 41.9 | 1975-08-04 | 2 | 39°14'N / 78°02'W | 0.80 Mile | 100 Yards | 0 | 0 | 250K | 0 | Clarke | |
| 42.1 | 1954-04-25 | 2 | 39°50'N / 77°14'W | 39°48'N / 76°59'W | 13.30 Miles | 500 Yards | 0 | 0 | 25K | 0 | Adams |
| 42.6 | 1989-06-20 | 2 | 40°22'N / 77°30'W | 2.00 Miles | 23 Yards | 0 | 1 | 25K | 0 | Perry | |
| 46.8 | 2004-09-17 | 2 | 39°10'N / 78°10'W | 39°12'N / 78°09'W | 5.00 Miles | 125 Yards | 0 | 0 | 250K | 0 | Frederick |
| Brief Description: An F2 tornado produced a nearly continuous path of damage for 5 miles in eastern Frederick County. It touched down west of Millwood Pike near the Winchester Airport. Three homes suffered roof damage, a detached two car garage was destroyed, a platform deck was blown away, an office trailer was overturned, and numerous trees along the track of the storm were uprooted or topped. | |||||||||||
| 47.2 | 1978-08-28 | 2 | 39°48'N / 77°02'W | 39°45'N / 77°00'W | 3.30 Miles | 20 Yards | 0 | 0 | 3K | 0 | Adams |
| 47.5 | 1980-06-07 | 3 | 39°56'N / 77°01'W | 1.50 Miles | 400 Yards | 0 | 0 | 250K | 0 | Adams | |
| 47.5 | 1980-06-07 | 2 | 40°01'N / 77°04'W | 40°02'N / 77°01'W | 2.30 Miles | 800 Yards | 0 | 0 | 2.5M | 0 | Adams |
| 47.9 | 1955-08-19 | 2 | 40°24'N / 77°23'W | 0 | 0 | 25K | 0 | Chester | |||
| 48.8 | 1978-08-28 | 2 | 39°45'N / 77°00'W | 39°43'N / 76°59'W | 1.90 Miles | 33 Yards | 0 | 0 | 3K | 0 | York |
* The information on this page is based on the global volcano database, the U.S. earthquake database of 1638-1985, and the U.S. Tornado and Weather Extremes database of 1950-2010.