Snohomish County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Snohomish County: 0.
2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Every large fire

1. Large fires mapped by the Monitoring Trends in Burn Severity program since 1984: 1,000 acres or more in the West, 500 or more in the East. Prescribed burns are excluded. Acres here are the part of each perimeter inside this place.

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service), 1984 to 2026.

Smoke overhead

1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

Claims by ZIP code

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

River gauges

1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

Every earthquake of magnitude 4 or more within 50 miles

1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

Tsunamis

1. Places where NOAA's Global Historical Tsunami Database records a tsunami's water arriving, with the greatest height it reached above sea level at the time. Only tsunamis NOAA rates probable or definite are counted. Heights from eyewitness accounts and tide gauges are mixed, and older events are less completely recorded.

NOAA NCEI/WDS Global Historical Tsunami Database, retrieved October 30, 2026.

Volcanoes within 100 miles

1. U.S. volcanoes within 100 miles, from the USGS Volcano Hazards Program. The threat category is the USGS 2018 National Volcanic Threat Assessment, which ranks volcanoes by how hazardous their past eruptions were and how many people and how much infrastructure lie near them. It is not a forecast of eruption.

USGS Volcano Hazards Program, retrieved October 30, 2026.

Mapped landslides

Mapped by WA WGS (19,449), USGS WA Puget Sound (315), NASA (72), West Coast Slow Moving (Yuankun and others, 2021) (8), USGS Seismogenic Mass Movements (3).

Deadly landslides

1. Landslides mapped in the USGS compilation of landslide inventories across the United States (version 3.0, 2025), rated probable or better. The compilation joins inventories made by federal and state agencies for different purposes and areas, so the number mapped in a county reflects how closely it has been surveyed as much as how often its slopes fail. An area with few records may simply not have been mapped. Deaths are as recorded in the inventories; a slide listed in two inventories is counted once.

USGS Landslide Inventories across the United States, version 3.0, retrieved October 27, 2026.

More event types since 1996

Costliest events since 1996

1. Mar 22, 2014Debris Flow$60.0 million
   National Weather Service narrative

   On a warm and dry 22nd of March, 2014, a large landslide occurred four miles east of the town of Oso, Washington. The slide debris, traveling at over 60 miles per hour, crossed the entire river valley, covering an area of over a square mile with an approximate deposit thickness of 15 to 75 feet in some areas. The force of the slide flow caused 43 fatalities, 12 injuries, destroyed 37 homes, and wiped out SR 530 for over a mile. In addition, the slide debris completely blocked the North Fork Stillaguamish River for over 24 hours, backing up a pool of water that flooded the valley about 2 miles upstream and reached approximately 20 feet deep, inundating an additional 6 homes. The…

2. Dec 3, 2007Heavy Rain$10.0 million
   National Weather Service narrative

   Over a dozen roads were closed due to high water and 20 families were evacuated from their apartments. Roads near Mill Creek and Edmonds will be closed for nearly a month to repair large sinkholes near and under the streets. About 300 residents had minor water damage to their homes.

3. Jan 7, 2009Flood$6.5 million
   National Weather Service narrative

   More than 50 roads in the county were flooded and about 40 were closed, including Highway 9. Highway 530 was closed in multiple locations. Schools in the Stanwood-Camano district were closed for 2 days. Most of Stanwood flooded, even businesses that hadn't flooded in 25 years. Many people were able to evacuate animals before the waters rose, however dozens had to leave via boat. Nearly 500 homes were flooded. Flood waters blew a hole in a dike on Ebey Island.

4. Nov 4, 2006Flood$3.3 million
   National Weather Service narrative

   Record flooding occurred on the Cowlitz, Nooksack, Puyallup, Nisqually, |Skykomish, Stillaguamish, Carbon, Snoqualmie, and Bogachiel. Major flooding occurred on the Tolt, Snohomish, Skokomish, Skagit, and White rivers. Other rivers flooding were the Satsop, Cedar, Wynoochee, Elwha, Deschutes, Dungeness, Skookumchuck, and Chehalis.

5. Nov 12, 2021Flood$2.4 million
   National Weather Service narrative

   Heavy rain and snow melt pushed a number of rivers above flood stage. Moderate flooding occurred on the Snohomish and Skykomish Rivers, with minor flooding on the Stillaguamish. Several pulses of heavy rain from the 3 atmospheric rivers sent the rivers above flood levels multiple times during the episode. Urban and small stream flooding also occurred.

6. Dec 12, 2010Flood$1.1 million
   National Weather Service narrative

   About 33 homes, and one business, were damaged in Granite Falls, Arlington, and Stanwood when the Stillaguamish River hit record flood stage. Parts of Highway 530 were closed. About 240 homes were issued a voluntary evacuation, while 6 people had to be rescued by hovercraft near Granite Falls.

7. Jan 12, 2021Flood$329,000
   National Weather Service narrative

   The Snohomish, Skykomish, and Stillaguamish Rivers exceeded flood stage. Urban and small stream flooding also occurred. Heavy rain caused some landslides.

8. Nov 17, 2015Flood$250,000
   National Weather Service narrative

   The Skykomish River in Snohomish County near Gold Bar crested at its third highest level on record, over 7 feet above flood stage, the highest level since the record-setting November 2006 flood. Flood waters swamped the town of Sultan, about six miles downstream from Gold Bar, prompting rescue of one woman forced to climb out her home's front window.

9. Nov 12, 2008Flood$100,000
   National Weather Service narrative

   Heavy rain caused flooding on 15 western Washington rivers, with eight river forecast points reaching major flood stage.

10. Jan 16, 2011Flood$50,000
    National Weather Service narrative

    Flooding on the North Fork of the Skykomish River finally uprooted and washed away a cabin near index (it had been eroding the land for many years). The South Fork of the Stillaguamish river undermined a section of the Mountain Loop Highway east of Granite Falls.

1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.

All-time high

100°F3 times, most recently Jun 28, 2021

All-time low

3°FJan 25, 1950

Warmest night

73°FJul 29, 2009

Coldest day

16°FJan 13, 1950

Wettest day

3.21 inJun 13, 1948

Hottest year

2015mean 53.8°F

Coldest year

1948mean 48.0°F

Wettest year

194845.38 in

Driest year

202514.42 in

Station Everett Snohomish County Airport (USW00024222), 548 ft elevation, 4.4 miles from the population centre. Daily records from 1948 to October 26, 2026; 93.2% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

Neighbouring counties

• Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
• Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
• Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
• Storm events NOAA NCEI Storm Events Database, through 2026.
• Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
• Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
• Weather records NOAA NCEI Global Historical Climatology Network Daily, station USW00024222.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
• Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
• Tsunamis NOAA NCEI/WDS Global Historical Tsunami Database.
• Volcanoes USGS Volcano Hazards Program, U.S. volcanoes and 2018 threat assessment.
• Landslides USGS Landslide Inventories across the United States, version 3.0 (2025).
• Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.