(KPAX) Where does National Weather Service Meteorologist Corby Dickerson start when explaining the sweltering heatwave that has taken hold of the northwestern United States and southwestern Canada?

According to Dickerson, “something this anomalous, particularly to our west ...  it has a lot of climatologists scratching their heads.”

Portland, Oregon -- 116°. Seattle, Washington -- 108°. Spokane, Washington -- 109°. Those cities each set all-time record highs on Tuesday. In addition, British Columbia hit an astounding all-time record in Canada of 121°. It's all due to a historic shift in high pressure.

“The four corners high decided to go on a vacation to British Columbia. To have the center of high-pressure sitting along the Canadian border between Washington and Idaho in British Columbia and have it register as strong as it is right now is beyond anything in the last hundred years climatology," Dickerson said.

Most of western Montana fell under the influence of this unusually strong ridge of high pressure on Sunday. For some in northwest Montana, it’s our fourth straight day of triple digits. Missoula has reached at least 99 for the third straight day. Comparisons to the historically hot summer of 2007 are already being drawn.

“We received four consecutive 100° plus days which is amazing in Missoula we had I believe all but three days that month were above 90," Dickerson told MTN News.

Back in 2007, Missoula reached at least 90° an impressive 53 days, at least 95° on 23 days, and topped out at 100° or higher 11 days -- including the all-time record of 107° on July 6. In all, July 2007 hit the 90° mark on 30 of 31 days.

“Over time the high is going to recede back to where it should be around the four corners of the United States," Dickerson said. "What is certain it seems is through about the first week to 10 days of July we should be seeing temperature is continuing to be well above normal.”

So, yes -- 2021 has a long way to go before we can fully compare it to 2007, but we have nearly a full set of summer days to go, and we’re off to a torrid start.

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