Weathercatch: What’s blowing in that wild autumn wind?

Following a two-week streak of unusually warm temperatures, last weekend the Inland Northwest experienced an abrupt shift to the wild side of October. No wonder it ties with April for having more seesawlike weather changes than any other month of the year.

Last week was spectacular, with brilliantly sunny skies in Spokane and the surrounding area. On Oct. 6-7, high temperatures ran in the low 80s. On Friday, temperatures lingered in the mid-70s as conditions remained dry and summerlike. That evening, residents flocked to parks and bike trails and sat outdoors at restaurants and pubs.

The next morning, those same people woke to chilly mid-40s temperatures and needed sweaters and rain coats to spend time outdoors. They also had to brace themselves against wind gusts of up to 38 mph that whipped some of the bright fall leaves off the trees.

Then, on Monday , the National Weather Service in Spokane issued a high wind watch for Tuesday calling for gusts up to 50-60 mph.

Just like that, summer weather switched to hardcore autumn.

Driving the surge of cool temperatures and much-needed rain was a strong cold front fueled by the jet stream as it plunged southward from Canada. Needless to say, it led to a dramatic seasonal shift as the region transitions from summer to winter.

None of which is unusual for this time of year. October is notorious for its striking weather changes. One day it’s warm, sunny and calm; the next it’s as cold, wet and windy as an angry spirit. In Spokane, the average high temperature drops from 66 degrees at the beginning of the month to 50 degrees by Halloween. The average low dips from 42 degrees to near freezing.

That said, here’s what much of the Inland Northwest can expect between now and the end of the month:

• First freeze: The average date of the season’s first 32-degree temperature is Oct. 9 in Spokane and earlier in higher elevations such as Republic, Omak and Colville. Obviously, that’s not the case this year, as the high temperature ran in the 70s on that date. Nonetheless, deepening fall weather has set the stage for an overnight freeze very soon.

• First snow: Although Spokane’s first snowfall usually arrives in November, it often gets a light flurry or two in October. Last year was a stark exception, however, when a record-breaking 3.6 inches of snow hit Spokane Oct. 8-9, with two more snowfalls before Halloween.

• More wind, more often: Winds, or flowing air currents, increase in October as warm air rises and cooler air takes its place – just as we experienced this week. Winds from the north will increasingly bring us colder temperatures as well. On Oct. 28 last year, an arctic cold front brought wind gusts as high as 60 mph and a burst of snow that resulted in numerous road closures in North Idaho and Eastern Washington.

• More cloudiness: As more unsettled weather patterns move through, October experiences increasing clouds compared with summertime and September.

• Less daylight: We’re losing almost 3 ½ minutes of light each day. Where Oct. 1 gave us 11 hours, 38 minutes of daylight, by the time we reach Halloween, we’ll have 9 hours, 58 minutes. By comparison, we got about 12 hours of daylight on Sept. 22, which was the autumn equinox.

• Surprising autumn amber: As rain and winds strip more leaves off maples, aspens and elders, there’s one tree that will continue to blaze. The tamarack, also known as the American larch, is the only member of the pine family that sheds its needles each year. But before that happens, the needles turn electric amber. They start to peak around Halloween, adding gusto to Eastern Washington landscapes into November as other trees lose their fall colors.