Weathercatch: Spokane’s rainiest month ever happened to be October seven years ago

Rain, rain and more rain. No, not the rain that moved into the Inland Northwest early this week following a period of gloriously warm, sunny weather. We’re talking about the record-shattering rainfall that deluged our region seven years ago this month.

In October 2016, more rain fell in Spokane than during any other month. To be clear – not only was it the rainiest October on record, it was the rainiest month ever since the National Weather Service in Spokane began keeping records in 1881. Today it remains the city’s all-time wettest month during those 142 years.

That said, if our spell of splendid fall weather feels unfairly halted by this week’s arrival of gloomy skies and rain, consider the prolonged soggy gloom of October 2016. In Spokane, 25 of the month’s 31 days were wet and cloud-filled. Only six days were rain-free, and unfortunately for trick-or-treaters, Halloween wasn’t one of them.

By the end of that month, Spokane International Airport received 6.23 inches of rain, which is five times the October average of 1.25 inches. The amount eclipsed the previous all-time rainfall record of 5.85 inches set in November 1897.

November, by the way, tends to feature notably increasing precipitation in the Inland Northwest. October, however, is more middle of the road, making the month’s 6.23-inch rainfall total an extreme weather event for our region.

Some days it poured. Other days it was a short shower or a long, steady drizzle. Of the 25 days it rained, the two most drenching were Oct. 13, when 0.94 inches fell, and Oct. 30, at 0.91 inches. Spokane saw measurable rain seven days in a row from Oct. 4-10, followed by 10 days in a row from Oct. 13-22.

And we had lots of soaking-wet company. A record-breaking 9.26 inches of rain fell in Priest River and 9.19 in St. Maries. Coeur d’ Alene saw 6.86 inches and Pullman, Moscow and Davenport received roughly 5.5 inches, setting records for their wettest October. In Yakima, a city synonymous with sunshine, 2.5 inches was recorded, four times its normal October total. Seattle picked up more than 10 inches of rain, and Portland nearly tripled its average October rainfall amount with 8.31 inches.

Where did all of the precipitation come from? A strong jet stream steered a series of storm systems from the Eastern Pacific directly into the Pacific Northwest. The jet stream also drew in moisture from a withering tropical storm that had developed southeast of Japan in early October.

Not surprisingly, on the final day of October, 0.38 inches fell in Spokane. After a month of drips, splashes and soggy ground, only the mushrooms were happy.

As for October 2023, clouds are expected to break this afternoon and produce mostly sunny skies Thursday. A chance of rain returns this weekend and should linger into next week. Spokane will likely see some more wet periods this month, but rest assured, it will be nothing like October 2016.

Nic Loyd is a meteorologist in Washington state. Linda Weiford is a writer in Moscow, Idaho, who’s also a weather geek.