Multnomah County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Multnomah 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.

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 OR DOGAMI (6,377), NASA (96), USGS Conterminous (1).

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. Sep 7, 2020High Wind, North Oregon Cascades$1.0 billion
   National Weather Service narrative

   The Horse Creek RAWS (HSFO3) recorded a peak gust of 66 mph.

2. Dec 7, 2015Heavy Rain$1.1 million
   National Weather Service narrative

   Heavy rain resulted in urban flooding and small stream flooding throughout the Portland Metro area. The rain was heavy enough to collapse a roof of a business in Gresham Oregon, cause a sink hole near Mt Hood College. High water flowing into Fairview Creek in Gresham snapped a sewage line. Several roads were closed due to high water and the Trimet Max operations were interrupted. water crept into businesses and homes. There were at least two land slides in Portland; one on Corbett Hill, and the other on Cornell Road.

3. Dec 7, 2015Flood$1.1 million
   National Weather Service narrative

   Heavy rain resulted in Johnson Creek to exceed major flood stage. Water from the river flooded homes, vehicles, and businesses. Several roads were closed due to the high water.

4. Dec 8, 2015Heavy Rain$621,000
   National Weather Service narrative

   Heavy rain resulted in urban flooding across the Portland metro area. All Amtrack and freight trains were shut down between Portland and Vancouver due to flooding. A mobile home park in Gresham flooded. There were a couple of land slides on Highway 30 where debris covered the highway. One of these slides was near German Town Road. The other slide was near the St John's Bridge, hit a car (with no injuries) as it happened, and covered all lanes of Highway 30.

5. Dec 17, 2015Heavy Rain$311,000
   National Weather Service narrative

   Heavy rain resulted in new daily rainfall records for the Portland International Airport and downtown Portland. A new daily rainfall of 1.87 inches at the airport broke the previous record of 1.02 inches from 1972. Downtown Portland measures 2.42 inches of rain on the 17th which broke the previous record of 2.26 inches from 1884. Standing water was reported on many roads in the area. The heavy rain caused a landslide on Highway 30 near the St John Bridge.

6. Oct 31, 2015Heavy Rain$150,000
   National Weather Service narrative

   Heavy rain combined with clogged drains from leaves resulted in urban flooding. The Portland Fire and Rescue received 32 calls in regards to street flooding, and assisted travelers in 5 cars from their stalled or trapped cars to dry land. Four roads were closed in the area for high water, and several Max lines were cancelled due to flooding under bridges. Thirteen Max trains were damaged by water and will be out of service for up to 2 weeks. One roof collapsed from the weight of rain water after the roof drains had been clogged, and several homes or businesses had flooded basements. A tree had fallen onto and damaged a parked car.

7. Dec 7, 2015Strong Wind, North Oregon Cascades$69,000
   National Weather Service narrative

   The media reported that several downed trees closed Highway 26 in Rhododendron.

8. Feb 13, 2025Heavy Snow, West Columbia River Gorge I-84 Corridor$60,000
   National Weather Service narrative

   Around 20 to 30 vehicles were involved in a series of crashes 3 miles west of Multnomah falls on I-84 1000-1200 02/13 due to snow, road ice, and low visibility. This impact verifies the warning. Based on LSRs in the region between 2-4.5 inches of snow likely fell.

9. Jun 19, 2005Lightning$50,000
10. Jun 10, 2022Heavy Rain$50,000
    National Weather Service narrative

    Heavy rains caused a large tree to fall, bringing down power lines across Highway 30 near the St. Johns Bridge, closing the highway in both directions for about 2 hours. The fallen tree also hit a house near the bridge. A daily record rainfall was recorded at Portland International Airport of 1.42 inches on the 10th.

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

116°FJun 28, 2021

All-time low

−3°FFeb 2, 1950

Warmest night

75°FJun 28, 2021

Coldest day

14°FDec 30, 1968

Wettest day

2.69 inNov 19, 1996

Snowiest day

14.4 inJan 21, 1943

Hottest year

2015mean 57.4°F

Coldest year

1964mean 50.1°F

Wettest year

199663.20 in

Driest year

198522.48 in

Snowiest season

44.5 in1949-50

Station Portland International Airport (USW00024229), 22 ft elevation, 5.5 miles from the population centre. Daily records from 1938 to October 26, 2026; 100.0% 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 USW00024229.
• 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.
• 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.