Snohomish County Natural Disasters and Weather Extremes
The chance of earthquake damage in Snohomish County is lower than Washington average and is higher than the national average. The risk of tornado damage in Snohomish County is about the same as Washington average and is much lower than the national average.
Earthquake Index, #5
| Snohomish County | 2.88 |
| Washington | 4.04 |
| 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, #13
| Snohomish County | 0.0077 |
| Washington | 0.0135 |
| 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, #9
| Snohomish County | 10.65 |
| Washington | 9.06 |
| 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 411 other weather extremes events within 50 miles of Snohomish 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: | 1 | Blizzard: | 0 | Cold: | 1 | Dense Fog: | 0 | Drought: | 3 |
| Dust Storm: | 0 | Flood: | 80 | Hail: | 44 | Heat: | 0 | Heavy Snow: | 30 |
| High Surf: | 0 | Hurricane: | 0 | Ice Storm: | 0 | Landslide: | 0 | Strong Wind: | 47 |
| Thunderstorm Winds: | 27 | Tropical Storm: | 0 | Wildfire: | 8 | Winter Storm: | 1 | Winter Weather: | 2 |
| Other: | 167 | ||||||||
Volcanos Nearby
A total of 3 volcanoes are found in or near Snohomish County.
| Distance (miles) | Name | Region | Latitude | Longitude | Elevation (foot) | Type | Status | Last Eruption |
| 30.4 | Glacier Peak | US-Washington, United States | 48.112 | -121.113 | 3213 | Stratovolcano | Tephrochronology | Last known eruption 1700-1799 |
| 50.5 | Baker | US-Washington, United States | 48.786 | -121.82 | 3285 | Stratovolcano | Historical | Last known eruption 1800-1899 |
| 81.8 | Rainier | US-Washington, United States | 46.87 | -121.758 | 4392 | Stratovolcano | Dendrochronology | Last known eruption 1800-1899 |
Historical Earthquake Events
A total of 18 historical earthquake events that had recorded magnitudes of 3.5 or above found in or near Snohomish County.
| Distance (miles) | Date | Magnitude | Depth (km) | Latitude | Longitude |
| 45.3 | 1945-04-29 | 5.5 | N/A | 47.4 | -121.7 |
| 48.3 | 1965-10-23 | 4.8 | N/A | 47.5 | -122.4 |
| 36.3 | 1969-11-10 | 4.7 | N/A | 48.52 | -121.4 |
| 39.0 | 1971-12-28 | 4.4 | 27 | 47.58 | -122.22 |
| 45.4 | 1977-07-10 | 4.3 | 11 | 48.53 | -122.45 |
| 10.1 | 1969-11-01 | 4.1 | N/A | 47.92 | -121.85 |
| 29.0 | 1964-10-15 | 4.1 | N/A | 47.7 | -122.1 |
| 44.7 | 1979-11-26 | 4.1 | 20 | 48.54 | -122.41 |
| 33.0 | 1978-12-31 | 4 | 20 | 47.58 | -121.85 |
| 34.8 | 1970-02-10 | 3.9 | 33 | 47.7 | -122.3 |
| 11.1 | 1980-09-19 | 3.8 | 6 | 47.91 | -121.87 |
| 31.2 | 1981-11-12 | 3.7 | 26 | 47.94 | -122.42 |
| 39.4 | 1966-06-11 | 3.7 | N/A | 47.83 | -122.55 |
| 13.1 | 1981-03-15 | 3.6 | 5 | 47.99 | -121.5 |
| 32.6 | 1976-01-31 | 3.6 | 18 | 48.35 | -122.32 |
| 36.9 | 1979-02-01 | 3.6 | 9 | 47.53 | -121.92 |
| 31.4 | 1973-06-09 | 3.5 | N/A | 47.6 | -121.8 |
| 48.4 | 1981-11-26 | 3.5 | 22 | 47.65 | -122.62 |
Historical Tornado Events
A total of 3 historical tornado events that had recorded magnitude of 2 or above found in or near Snohomish County.
| Distance (miles) | Date | Magnitude | Start Lat/Log | End Lat/Log | Length | Width | Fatalities | Injuries | Property Damage | Crop Damage | Affected County |
| 17.2 | 1986-05-13 | 2 | 48°13'N / 122°03'W | 0.30 Mile | 33 Yards | 0 | 0 | 0K | 0 | Snohomish | |
| 20.2 | 1970-11-24 | 2 | 48°06'N / 122°12'W | 0.30 Mile | 30 Yards | 0 | 0 | 25K | 0 | Snohomish | |
| 46.2 | 1969-12-12 | 3 | 47°30'N / 122°24'W | 47°32'N / 122°19'W | 3.80 Miles | 100 Yards | 0 | 1 | 250K | 0 | King |
* 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.