Lyman County Natural Disasters and Weather Extremes
The chance of earthquake damage in Lyman County is about the same as South Dakota average and is much lower than the national average. The risk of tornado damage in Lyman County is lower than South Dakota average and is lower than the national average.
Earthquake Index, #12
| Lyman County | 0.08 |
| South Dakota | 0.05 |
| 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
| Lyman County | 0.0000 |
| South Dakota | 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, #34
| Lyman County | 79.20 |
| South Dakota | 114.73 |
| 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 6,115 other weather extremes events within 50 miles of Lyman County 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: | 19 | Cold: | 3 | Dense Fog: | 0 | Drought: | 6 |
| Dust Storm: | 0 | Flood: | 234 | Hail: | 3,644 | Heat: | 0 | Heavy Snow: | 23 |
| High Surf: | 0 | Hurricane: | 0 | Ice Storm: | 2 | Landslide: | 0 | Strong Wind: | 19 |
| Thunderstorm Winds: | 2,035 | Tropical Storm: | 0 | Wildfire: | 11 | Winter Storm: | 12 | Winter Weather: | 21 |
| Other: | 86 | ||||||||
Volcanos Nearby
No volcano is found in or near Lyman County.
Historical Earthquake Events
A total of 2 historical earthquake events that had recorded magnitudes of 3.5 or above found in or near Lyman County.
| Distance (miles) | Date | Magnitude | Depth (km) | Latitude | Longitude |
| 30.5 | 1983-03-04 | 4.6 | 5 | 44.21 | -99.41 |
| 25.8 | 1967-11-23 | 4.4 | N/A | 43.7 | -99.4 |
Historical Tornado Events
A total of 25 historical tornado events that had recorded magnitude of 2 or above found in or near Lyman County.
| Distance (miles) | Date | Magnitude | Start Lat/Log | End Lat/Log | Length | Width | Fatalities | Injuries | Property Damage | Crop Damage | Affected County |
| 8.5 | 1987-08-05 | 2 | 44°01'N / 99°52'W | 1.20 Miles | 80 Yards | 0 | 0 | 250K | 0 | Lyman | |
| 11.2 | 1971-07-09 | 3 | 43°53'N / 99°37'W | 0 | 2 | 0K | 0 | Lyman | |||
| 16.6 | 1960-07-25 | 2 | 43°55'N / 100°17'W | 43°55'N / 100°04'W | 10.40 Miles | 33 Yards | 0 | 0 | 25K | 0 | Lyman |
| 17.7 | 1971-07-09 | 3 | 44°05'N / 99°36'W | 0 | 0 | 0K | 0 | Lyman | |||
| 23.0 | 1992-06-16 | 3 | 44°03'N / 99°26'W | 2.00 Miles | 73 Yards | 0 | 8 | 25.0M | 0 | Buffalo | |
| 23.7 | 1971-06-04 | 2 | 43°55'N / 100°19'W | 0 | 0 | 0K | 0 | Lyman | |||
| 27.6 | 1971-07-24 | 3 | 43°46'N / 99°19'W | 2.50 Miles | 300 Yards | 0 | 0 | 0K | 0 | Brule | |
| 31.9 | 1965-05-08 | 2 | 43°40'N / 99°14'W | 43°43'N / 99°18'W | 4.30 Miles | 100 Yards | 0 | 0 | 25K | 0 | Brule |
| 32.7 | 1971-06-04 | 2 | 43°54'N / 100°30'W | 0 | 0 | 25K | 0 | Jones | |||
| 32.8 | 1992-06-30 | 2 | 44°22'N / 99°55'W | 0.30 Mile | 30 Yards | 0 | 0 | 25K | 0 | Hughes | |
| 35.0 | 1954-06-10 | 2 | 43°43'N / 99°11'W | 1.00 Mile | 30 Yards | 0 | 0 | 25K | 0 | Brule | |
| 36.5 | 2010-05-22 | 2 | 43°22'N / 99°52'W | 43°22'N / 99°48'W | 3.00 Miles | 150 Yards | 0 | 0 | 80K | 0K | Tripp |
| Brief Description: EVENT NARRATIVE: A tornado tracked along East 3rd Street in Winner, blowing down carports, trees, and tractor-trailers. A large barn was destroyed east of Winner; the curved roof was blown off in one piece and tossed across a corral. Another machine shed was blown apart. Based on the extent of the damage, wind speeds were estimated around 75 mph through town with peak winds 95 to 115 mph. EPISODE NARRATIVE: Large hail and strong wind gusts accompanied a severe thunderstorm over southern Todd and Tripp Counties. A tornado crossed the town of Winner, causing minor damage in town and destroying two barns east of town. | |||||||||||
| 36.8 | 1957-06-30 | 2 | 43°22'N / 99°45'W | 0 | 0 | 25K | 0 | Tripp | |||
| 38.3 | 1971-07-03 | 3 | 44°16'N / 99°14'W | 44°15'N / 99°17'W | 0 | 0 | 25K | 0 | Hand | ||
| 39.6 | 1968-06-20 | 2 | 43°23'N / 99°26'W | 43°44'N / 98°58'W | 33.50 Miles | 33 Yards | 0 | 0 | 0K | 0 | Gregory |
| 40.3 | 1973-07-23 | 3 | 44°21'N / 100°21'W | 2.50 Miles | 500 Yards | 0 | 10 | 2.5M | 0 | Hughes | |
| 42.1 | 1971-06-04 | 2 | 43°30'N / 100°29'W | 0.30 Mile | 50 Yards | 0 | 0 | 0K | 0 | Mellette | |
| 42.6 | 1957-04-18 | 2 | 43°15'N / 99°44'W | 43°19'N / 99°43'W | 3.80 Miles | 33 Yards | 0 | 0 | 3K | 0 | Tripp |
| 42.7 | 1968-06-20 | 2 | 44°22'N / 100°24'W | 0 | 0 | 0K | 0 | Stanley | |||
| 43.0 | 1973-07-01 | 2 | 43°50'N / 98°59'W | 0.30 Mile | 50 Yards | 0 | 1 | 25K | 0 | Brule | |
| 45.5 | 1986-07-28 | 2 | 43°47'N / 99°00'W | 43°43'N / 98°54'W | 6.00 Miles | 80 Yards | 0 | 0 | 250K | 0 | Brule |
| 47.6 | 1965-05-08 | 5 | 43°00'N / 99°43'W | 43°26'N / 99°38'W | 30.10 Miles | 1760 Yards | 0 | 1 | 2.5M | 0 | Tripp |
| 48.0 | 1965-05-08 | 2 | 43°11'N / 99°50'W | 43°13'N / 99°48'W | 0 | 0 | 0K | 0 | Tripp | ||
| 48.2 | 1971-10-18 | 2 | 43°13'N / 99°32'W | 43°15'N / 99°32'W | 2.30 Miles | 367 Yards | 0 | 0 | 25K | 0 | Turner |
| 49.0 | 1971-07-03 | 2 | 44°13'N / 99°00'W | 44°14'N / 98°56'W | 2.30 Miles | 100 Yards | 0 | 0 | 25K | 0 | Hand |
* 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.