Walla Walla County

Every recorded tornado

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

Mapped landslides

Mapped by WA WGS (18).

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. Feb 6, 2020Flood$8.8 million
   National Weather Service narrative

   Record high water levels were seen on Upper Mill Creek with extensive damage along upper Mill Creek to homes as well as roads and bridges. A number of residents had to be evacuated via helicopter or 4 wheeler. There was minimal damage along Mill Creek through Walla Walla as water was diverted through the Mill Creek Flood Project. Downstream of Walla Walla, there was damaging flooding in College Place with a bridge being washed out near Wallula Road. In Waitsburg, flood waters from both the Touchet River and Coppei Creek inundated the town as levees were damaged. 60 homes were damaged as well as numerous roads and bridges. Damage countywide is estimated at 8.77 million dollars.…

2. Jul 16, 2012Flash Flood$1.3 million
   National Weather Service narrative

   Thunderstorms training from south southwest to north northeast over the narrow path produced an estimated 1 to 2 inches of rainfall and caused flash flooding and mud slides. A parked pickup truck was completely submerged. Over a dozen county roads were damaged.

3. Apr 27, 2018Strong Wind, Lower Columbia Basin$1.0 million
   National Weather Service narrative

   Power outages along Canal Drive in Kennewick and in the Garfield Hill subdivision of SE Kennewick. Strong winds in the Finley area (south of Kennewick) blew down tree branches 4 inches in diameter and produced blowing dust reducing visibility to 1/10th of a mile.

4. May 19, 2006Thunderstorm Wind$1.0 million
   National Weather Service narrative

   Downburst destroyed a large storage building and grain bin, flipped a tractor trailer rig onto a dump truck, and overturned an irrigation pivot. Hundreds of trees were downed on a tree farm.

5. Dec 17, 2012High Wind, Lower Columbia Basin$560,000
   National Weather Service narrative

   A strong Pacific storm system brought a mixture of weather and high winds to the lower elevations. ||Several reports of high wind gusts and damage came in from the Tri-Cities area, as this was the area hit hardest. ||Reports of damage and wind gusts in MPH include: Shingles blown off of a roof 4 NE of Kennewick, 14 NNW of West Richland (72 ), Barricade Mesonet (58), 12 NW of West Richland (69), Benton City (83), Hanford (66), Richland Airport (76), 3 WNW Kennewick (63), Pasco Airport (70), 5 ENE Prosser (62), 6 S Touchet (58), 6 NNW Walla Walla a trained spotter measured gust (60) and reported tree branches 2-4 in diameter down, along with power out at the Walla Walla watershed…

6. May 3, 2010High Wind, Lower Columbia Basin$500,000
   National Weather Service narrative

   A tight pressure gradient combined with a cold frontal passage to produce widespread high winds and damage. Blowing dust reduced visibility to near zero in portions of the Yakima Valley and Lower Columbia Basin and forced road closures. Peak wind gusts in mph included 15 miles west of Basin City (77), 8 miles northwest of Richland (59), 1 mile northwest of Richland (58), Benton City (58), 5 miles south of Eltopia (58), 1 miles north northeast of College Place (58), 8 miles northwest of West Richland (74), and High Bridge RAWS (59). Sustained winds at least 40 mph were reported 8 miles north of Dayton and 2 miles west northwest of College Place. Downed trees, branches, power lines…

7. Feb 7, 2002High Wind, Lower Columbia Basin$300,000
   National Weather Service narrative

   High wind caused over 800 people to lose power when trees fell on the power lines in Pasco and Finley. Two tractor trailers were overturned, one on Interstate 82 and the other on Interstate 182, but no injuries were reported. Fences were blown down the street into neighboring houses, causing damages to roofs. The Pasco ASOS reported a gust to 60 mph.

8. May 19, 2006Thunderstorm Wind$250,000
   National Weather Service narrative

   Wind blew off roof from 40 x 60 foot warehouse. Two 2500 gallon tanks blown over. Irrigation pivot damaged and service station sign blown down.

9. Apr 9, 2019Flood$150,000
   National Weather Service narrative

   Minor flooding was reported on Titus Creek, stemming from log jam on Mill Creek that pushed more water into Titus Creek. As a result of high water on Titus Creek, a tractor was flooded. The Touchet River, 1.5 to 3 miles east of Waitsburg, changed course and began channeling water against a resident's property. The resulting erosion caused two outbuilding to topple into the water.

10. Jan 23, 2001Dense Fog, Lower Columbia Basin$140,000
    National Weather Service narrative

    Dense fog and icy roads led to a 12 vehicle chain-reaction collision on Interstate-82 south of the Tri-Cities. This accident lead to several injuries and closed the southbound lanes for 7 hours.

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 29, 2021

All-time low

−24°FDec 30, 1968

Warmest night

80°F4 times, most recently Jun 30, 2021

Coldest day

−9°FDec 30, 1968

Wettest day

3.64 inJul 23, 1992

Snowiest day

11.0 inFeb 24, 1994

Hottest year

2015mean 57.4°F

Coldest year

1955mean 50.5°F

Wettest year

198126.68 in

Driest year

202111.71 in

Station Walla Walla Regional Airport (USW00024160), 1,170 ft elevation, 5.2 miles from the population centre. Daily records from 1949 to October 25, 2026; 93.1% 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 USW00024160.
• 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.
• 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.