Spokane Windstorm Season: How to Protect Your Trees (and Your House)

Spokane gets hammered by sustained windstorms every spring (March–May) and fall (October–December). 50+ mph gusts are routine. 70+ mph gusts happen most years. And every year, the same scenario plays out: trees that showed warning signs months earlier finally fail, and homeowners are stuck with insurance claims, roof damage, and weeks of disruption.

The good news: 80% of Spokane storm tree damage is preventable with a one-hour seasonal walkthrough. Here's the playbook.

When to Prep (and Why Timing Matters)

• Spring prep window: late February through mid-March (before March winds)
• Fall prep window: mid-September through early October (before October fronts)
• Avoid: pruning during active sap flow (April–May) on most species

The Pre-Storm Walkthrough Checklist

1. Walk every tree on your property and look for new lean

Compare to your mental picture from 6 months ago. Any tree that's leaning more than it was — especially toward a structure — needs immediate professional assessment.

2. Look up at the canopy

Dead branches over 4 inches diameter are widow-makers. They fall with little warning in moderate wind. Get them removed before storm season.

3. Inspect the trunk and base

Cracks, splits, mushrooms, hollow areas, and soil heaving are all critical warning signs. Don't ignore them and hope the tree makes it through.

4. Check trees near power lines

Avista will trim trees touching their primary lines for free — call (800) 936-6629. Trees near the service drop to your house are YOUR responsibility, and they cause most outages.

5. Note any beetle activity

Pitch tubes on ponderosas, woodpecker damage, sap weeping, or sawdust at the base — all signs the tree is beetle-killed and structurally compromised.

Strategic Pruning to Reduce Wind Load

Properly pruned trees withstand wind dramatically better than overgrown ones. Here's what professional pruning accomplishes:

• Crown thinning: reduces wind sail by 15–25% without changing tree shape
• Crown raising: removes lower branches that can catch wind and lever the trunk
• Deadwood removal: eliminates falling-branch hazards
• Hazard limb removal: targets specific branches over structures
• Crown reduction: shortens overextended branches that are leverage points in wind

Trees That Most Often Fail in Spokane Windstorms

Ponderosa pine

Number one storm casualty. Shallow roots, top-heavy canopy, brittle when drought-stressed. Especially failure-prone after beetle attack.

Black cottonwood

Massive limbs, weak branch attachment, and prone to internal decay. Cottonwoods near houses are a constant risk and almost always need professional management.

Lombardy poplar

Weak wood, fast growth, common bacterial canker. These trees are essentially designed to fail. If you have a row of Lombardy poplars near your home, talk to an arborist about phased removal.

Siberian elm

Brittle wood, weak branch unions, prone to dropping huge limbs in wind. Common in older Spokane neighborhoods like the South Hill and West Central.

What to Do During an Active Windstorm

• Stay away from windows on the side facing wind
• Move vehicles out from under trees if you have time before the storm
• Don't go outside to check trees during sustained winds
• If a tree falls on the house — get everyone to a center room and call 911 if anyone is injured
• Document the moment power goes out for insurance purposes

After the Storm

Walk your property before turning on power or going up onto the roof. Look for:

• Hanging branches not yet fallen ("widowmakers")
• Trees with new lean that survived the storm
• Damage to fences, outbuildings, vehicles, landscaping
• Any contact with overhead power lines

If you see anything questionable, get a professional assessment. The next windstorm is always within 60 days in Spokane.