"In the United States, the lowest temperature on record,–79.8°F, was recorded on January 23, 1971, at Prospect Creek Camp, which is located in the Endicott Mountains of Northern Alaska at latitude 66° 48′N, longitude 150° 40′W. The lowest temperature in the contiguous 48 states,–69.7°F, occurred on January 20, 1954, at Rogers Pass, in Lewis and Clark County, Montana. This location is in mountainous and heavily forested terrain, about 0.5 mi east of and 140 ft below the summit of the Continental Divide."
I'm doubtful of -60 at Jackson, but hey, who knows.
Source:
Weatherexplained.com
In the early 1970s, I remember daytime temperatures in Orono, Maine, remaining well below 0 F for weeks at a time, and the nighttime temperatures commonly dropping to - 40 F and my Datsun 510 wagon not starting for over two weeks during one extremely cold spell. But, I do not remember ever a -50 F in Orono.
When I was away from Pocatello, Idaho, during late December 1978, the temperatures in town dropped to the -55 F range, with many folks having their water valves freeze and burst. I lucked out being away, as my water lines and valves were empty, so no damage. During this same time frame, temperatures in West Yellowstone hit -60 F, and I seem to remember that some folks in the Park drank super cold alcohol and died.
I am surprised about that low record in the continental 48 being from such a high elevation, as the usual record low suspects are in valleys and holes from cold air drainage. But, I do not doubt that record, as the verification of such is rigorous.
I am thinking that it was perhaps this week five years ago that Kenny froze to death on South Twin? R.I.P.