We usually just get low negative digits during the winter at some point. The coldest I can remember it being here in central oregon was -25. I was Christmas break 1990. I was going to Oregon Institute of Technology at the time. It was -27 down in the Klamath Basin where the school is. Klamath Lake was frozen. There was a skift of snow on it and that showed tire tracks!.Insanity: there are a number of springs, plus the main channel of the Klamath (before the lake was damned), where the Lake’s ice would be thinner. No way to see them until you break through. Imagine driving halfway across its 17 mile width and plunging through the ice over the 40’ deep Klamath River. . 4 to 6" of mud under a frozen crust for several months during the winter. I took Surveying II during the winter and it was a bit chilly, especially by the third hour. (I was the only one dressed for the weather, wearing west German Bundeswehr woolens) The instruments would punch through the frozen layer, then mush down into the bentonite. It made it interesting getting the instruments to stay put. .That area had some pretty extreme weather. The first year of my engineering career, I worked for a firm in Klamath Falls. I’ve never liked snow much since: the first three weeks of january 1993, a weather system got stalled. It snowed continuously for 3+ weeks. 96 inches by the end of it. Had to walk over the gunk a couple of miles to get basic groceries. BLECH! It packed down some, but the birms in the roads were over 10 feet high. Took a couple of months for it all to melt.