Washington County, Oregon severe weather history spans 77 recorded events between 1954 and 2024. The dominant hazard is flood, accounting for 33.8% of all recorded events. It ranks #2,975 nationally and #18 in Oregon.
77
Recorded events
2
Direct deaths
0
Direct injuries
$5.7M
Property damage
The record
What the Washington County, Oregon severe weather history record shows
Across the archive, Washington County, Oregon severe weather history averages 1.1 recorded events a year. The busiest stretch on record is the 2000s, with 32 events logged in that decade alone. Roughly 4 events fall before 1990 and 73 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Washington County, Oregon record is flood, responsible for 2 direct deaths. The costliest is flood, with $5.1M in reported property damage. In total, 7 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Washington County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Flood | 26 | 2 | $5.1M | 0 | 2005–2024 |
| Heavy Rain | 20 | 0 | $265K | 0 | 2001–2024 |
| Hail | 8 | 0 | $1K | 1.75 | 1963–2023 |
| Funnel Cloud | 8 | 0 | $0 | 0 | 2003–2023 |
| Tornado | 6 | 0 | $128K | F1 | 1954–2018 |
| Lightning | 5 | 0 | $189K | 0 | 1999–2018 |
| Thunderstorm Wind | 4 | 0 | $24K | 52 | 2009–2022 |
Decade by decade
Washington County, Oregon severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
5 mapped tornado paths intersect this county: 4 touched down inside it and 1 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1993-12-08 | EF2 | 0 | 0 | 6.0 mi | Crossed in |
| 1991-11-12 | EF1 | 0 | 0 | 0.2 mi | Touched down here |
| 2018-10-29 | EF0 | 0 | 0 | 0.1 mi | Touched down here |
| 2004-06-18 | EF0 | 0 | 0 | 0.1 mi | Touched down here |
| 1966-06-23 | EF0 | 0 | 0 | 0.3 mi | Touched down here |
Significant events
Deadliest events on record in Washington County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Dec 4, 2023 | Flood | ALOHA | 1 | 0 | $0 |
| Dec 3, 2007 | Flood | DILLEY | 1 | 0 | $2.3M |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
The Tualatin River near Dilley flooded, causing flood damage to homes in the area and leaving some roads impassable. Old Hwy. 47 and Hwy. 47 were closed temporarily due to combined flooding of a couple creeks with the Tualatin River. Near the area, a 54 year old male drown in Hedges Creek, a tributary of the Tualatin River. NOTE: Damage estimates are for the entire county of Washington.
Heavy rain resulted in flooding of the Tualatin River near Dilly, and of many small creeks between Beaverton and Gaston. Around 50 homes sustained flood damage and many roads were closed including Highway 217 in Beaverton (during the evening commute).
Heavy rain from convective showers resulted in significant flooding near Beaverton. Flooding was reported of four homes, four apartments, several garages, the Winterhawks Skating Center, and a community pool. The city Public Works Director reported 2.3 inches of rain per hour, a personal weather station reported 2.29 inches of rain over 2 hours, and the National Weather Service Doppler radar estimated 1.7 inches per hour. A car stalled in a flooded high water in an underpass near the US 26-US 217 interchange. The cost damage is an estimate based on reports from the General Manager of the Skating Center and previous history of similar residential damage.
Context
Risk, population and federal disasters
Relatively High
FEMA NRI risk rating
603,947
Population (ACS)
$588K
Median home value
17
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Aug 9, 2024 | Fire | LEE FALLS FIRE | FM |
| Sep 15, 2020 | Fire | WILDFIRES AND STRAIGHT-LINE WINDS | DR |
| Sep 10, 2020 | Fire | WILDFIRES | EM |
| Sep 10, 2020 | Fire | CHEHALEM MOUNTAIN BALD PEAK FIRE | FM |
| Sep 8, 2020 | Fire | POWERLINE FIRE | FM |
| Mar 28, 2020 | Biological | COVID-19 PANDEMIC | DR |
Quick answers
Frequently asked
How many severe weather events have been recorded in Washington County, Oregon?
77 events are on record between 1954 and 2024, causing 2 direct deaths and $5.7M in property damage.
What is the most common severe weather hazard in Washington County?
Flood, with 26 recorded events — 33.8% of everything in the archive for this county.
How many tornadoes have crossed Washington County?
5 mapped tornado paths intersect the county boundary; 4 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Washington County?
17 federal disaster declarations from FEMA include Washington County, each tied to a specific incident period.
How risky is Washington County compared with the rest of the country?
FEMA's National Risk Index rates Washington County as relatively high risk, placing it in the 96 percentile of its state for expected annual loss.
Where does the Washington County, Oregon severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Wasco County 41
- Wheeler County 48
- Wallowa County 96
- Yamhill County 34
- Union County 147
- Umatilla County 263
Cite this page
“Washington County, Oregon.” Severe Weather History. severeweatherhistory.com/county/oregon/washington-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.