The September 2024 eastern Washington windstorm

What happened

The front was dry, but strong enough to build thunderstorms as it crossed eastern Washington in the afternoon. Instead of heavy rain, the storms delivered gusty outflow winds from their downdrafts: 61 mph at Spokane International Airport, 67 mph at the Pullman–Moscow airport and 69 mph at a station in Pullman. The wind lifted dry soil into dust storms.

Damage began around Oroville and Wannacut Lake in Okanogan County in early afternoon and spread east through Spokane, Whitman, Stevens, Pend Oreille and Asotin counties into the evening. Outages reached about 12,400 customers in Spokane County, 7,500 in Stevens, 2,400 in Pend Oreille and 800 in Whitman. In Oregon, La Grande gusted into the 50s and a metal shed blew over. NOAA’s Spokane office filed 30 thunderstorm wind reports for the afternoon and evening, most backed by a measured gust at a nearby airport or weather station.

The storm in NOAA’s numbers

NOAA’s Storm Events Database files this storm as 2 episodes from the National Weather Service offices in Spokane (OTX) and Pendleton (PDT), dated September 25, 2024. Counting the six tree-relevant report types (high wind, strong wind, thunderstorm wind, ice storm, winter storm and heavy snow), the episodes hold 31 reports: 1 strong wind and 30 thunderstorm wind (1 in Oregon; 30 in Washington). The highest gust among the wind reports is 60 knots (about 69 mph), measured, in Whitman County, Washington. 3 reports in these episodes appear to carry the gust in mph in NOAA’s knots field (the narrative quotes the same number in mph), so they are converted here. Of the counted reports, 21 mention trees in the narrative.

A report is one entry per forecast zone or county per event, so one storm crossing many zones produces many reports. Gusts are in knots as NOAA records them (1 kt is about 1.15 mph).

Affected counties

7 counties have at least one counted report (1 in Oregon; 6 in Washington). The most reports touched Spokane County, WA (14), Whitman County, WA (7) and Okanogan County, WA (4). Most wind, ice and snow reports are filed by forecast zone, and a zone report is assigned here to every county that zone covers, so a county’s number is the reports that touched it, not separate incidents.

Damage, deaths and injuries

NOAA’s property damage field for these episodes adds up to $35,500 in nominal dollars, as entered by the NWS offices at the time and not adjusted for inflation. The event records list no deaths or injuries across these episodes.

NOAA entered $35,500 across these reports, mostly $500 to $2,500 apiece, which reflects quick placeholder estimates rather than full repair costs. No deaths or injuries are recorded.

What it meant for trees

This is a tree storm in the plainest sense. Reports describe a large tree uprooted at Garry Middle School, a tree snapped near the top and dropped onto a house, several trees down at Whitworth University and in Corbin Park, a tree 4 feet in diameter blown over, and roads blocked by trees 8 to 12 inches thick. A branch crushed the roof of a car in Pullman, broken limbs fell on a camper and lines in Asotin County, and near Oroville an orchard lost several rows of trees.

Some of the damage came from gusts of 35 to 45 mph, well under high wind criteria. In late September trees are in full leaf after a dry summer, and a sudden downdraft hits a full crown with little warning. Near Deer Park a 15-foot maple about 5 inches thick went over in a 35 mph gust. Older street and park trees took much of the hit in Spokane: the reports name a middle school, a university campus and two city parks.

What homeowners can learn from it

• Lighten leafy trees before late-summer storms. Deadwood and heavy, end-weighted limbs fail first; see crown thinning and reduction.
• Outflow winds arrive fast. When afternoon thunderstorms are building, park away from large trees and stay out from under them; warnings for downdraft winds can come only minutes ahead. Of the 165 thunderstorm wind reports NOAA logged in Washington from 2016 to mid-2026, 144 fell between May and September (see Washington storm records).
• Photograph before anything is moved. Pictures of the tree, the stump or root plate and the damage are the evidence an insurer will want; storm damage and tree insurance in Oregon and storm damage and tree insurance in Washington explain what policies usually cover.
• If a tree is on the house, a car or a line, get people out of reach first. Then call the utility for anything touching wires; emergency tree service and fallen tree removal cover what happens next, and tree work safety explains why a crew should handle trees under tension.

Local pages: emergency tree service in Spokane, Pullman and Avista tree trimming. Before the next storm season, the tree risk checklist walks you around your own trees, and Oregon storm records and Washington storm records put this storm in context.

How this page was built

Every number above is computed from NOAA’s Storm Events bulk files for episodes 196580, 196876. Episodes were chosen by ranking all Washington and Oregon episodes from 2016 to mid-2026 on tree-relevant report counts, property damage and tree mentions, and episodes from different offices or states were merged when their narratives describe the same system on the same dates. NOAA files thunderstorm wind by county rather than forecast zone, so the county counts here need no crosswalk. The single Oregon report is a strong wind report from the same front. Damage figures are NOAA’s nominal-dollar estimates and are often blank. See all storms on the storm history index and the site’s methodology.