Now that it’s November, it goes without saying that our days will grow shorter and our weather cooler and wetter. But November also means there’s a good chance a windstorm or two will roll through the Inland Northwest.
Typically, March and April are the windiest months in our region. But the wind behaves differently during November. Instead of persistent kite-soaring weather, we’re more likely to experience a big wind event that produces winds strong enough to cause power outages and some degree of property damage.
In the past 20 years, 13 such storms have struck the area during the month of November. Two of them were monsters.
On Nov. 17, 2015, the worst windstorm in our region’s recorded history killed two women and left 200,000 people without power for 10 days. Wind gusts exceeding 70 mph uprooted hundreds of trees, some onto homes and cars. Winds also snapped power poles and wires, blew off entire roofs and grounded air travel. Six years later, another menacing storm roared into the Spokane area on Nov. 15, 2021, unleashing near-hurricane force winds that toppled trees, destroyed commercial signs and plunged homes and businesses into darkness. Although the two storms packed an equal amount of fury, peak winds during the 2021 event lasted a little over 2 hours, compared to 6 hours in 2015. That’s why there was far more destruction in 2015.
Going back 20 years, winds up to 45 mph barreled through southeastern Washington on Nov. 11, 2003, only to be followed by a second, larger storm on Nov. 18-19, when up to 60 mph winds were recorded, according to the National Weather Service Spokane.
“A tree fell on a car in Ritzville and another fell on a house in Spokane,” the agency reported on its website. Damage was also reported in Coeur d’Alene.
More recently, a strong windstorm struck the Spokane area and North Idaho the day before Thanksgiving on Nov. 27, 2019, causing a number of power outages from fallen trees and branches. And just last year, powerful winds splintered trees, tore shingles off roofs and left thousands without power on the night of Nov. 4.
Why is November so prone to windstorms? Several meteorological factors are at play this time of year:
- Strong low pressure systems are more likely to pass through the Inland Northwest, which can generate strong winds. During November, the polar region is cooling rapidly, while the tropics remain hot. The resulting large-scale temperature difference drives the formation of these lows.
- The Pacific jet stream is strengthening, and many of these strong low-pressure systems derive some of their energy from the jet stream. This, in turn, creates large pressure gradients that drive strong winds.
- Atmospheric rivers originating in the tropical Pacific Ocean are responsible for a number of powerful, widespread wind and rain storms that swoop into the Pacific Northwest during fall and winter. When these systems make landfall on the Washington coast, sometimes they move inland across the Cascade Range and into eastern Washington.
November 2023 has been a bumpy ride so far, with plenty of rain, breeziness and wind gusts reaching upwards of 35 mph on Tuesday.
After a brief break in the bustle on Wednesday and today, rain and breezy conditions are expected to resume either tonight or Friday morning. We could even see some snowflakes. No big windstorms, though. At least for now – after all, we’re only a little more than a week into the windstorm season.
Nic Loyd is a meteorologist in Washington state. Linda Weiford is a writer in Moscow, Idaho, who’s also a weather geek.