Weathercatch: Freezing to 100; what a difference a day makes in Inland Northwest

The heat wave that roasted the Inland Northwest last weekend through Tuesday of this week came late in the season. That was unusual enough. But how about the fact that two communities awoke to freezing temperatures only a day before temperatures began their dramatic climb?

Shortly before 6 a.m. on Friday, thermometers read 32 degrees in Uniontown and 31 in Colton – a rare occurrence in mid-August. The next day, temperatures began steeply ascending, eventually reaching their peak of near 100 on Sunday.

Earlier that day, an excessive heat warning went into effect through Tuesday across most of the Inland Northwest. “Dangerously hot conditions,” the National Weather Service-Spokane warned. “Prolonged daytime heat with little nighttime cooling …”

Unusual, indeed.

Spokane didn’t experience the extreme low-to-high temperature swing that Uniontown and Colton did. Even so, with a low of 48 last Friday morning, it was definitely on the cool side.

Then, just two days later, Spokanites – including millions of other people in the western United States – saw temperatures exceed 100 on Sunday.

In our region, Spokane reached a high of 101, compared with the average high of 83.

Yakima hit 102 and the Tri-Cities 104.

Meanwhile, a record was set in Lewiston-Clarkston, where the high temperature of 108 eclipsed the previous record of 106 for that date, set in 1897.

Even Western Washington sizzled, where Sunday marked the hottest day of the year.

Temperatures topped out at 98 in Seattle, just one degree shy of breaking the record set 11 years ago.

Though a notch or two cooler, extreme heat continued Monday and Tuesday as the Pacific Northwest remained snagged by the most far-reaching heat wave of the summer.

A strong ridge of high pressure, a phenomenon associated with primarily sunny skies and hot weather, has been anchored over the desert southwest. Late last week, the jet stream began pushing the system across more Western states and then northward into the Pacific Northwest.

As the heat wave swelled, Death Valley, California, surged to a stifling 130, one of the hottest temperatures ever recorded worldwide.

The spate of intense heat spawned a series of wildfires in Eastern Washington, including four in Spokane County, one east of Union Gap in Yakima County and another along the Snake River near Clarkston.

The sun will continue to beat down on us this weekend, but not as intensely. The forecast calls for sunny skies, highs hovering around 90 and lows in the upper 50s.