My mustache froze while riding the ski lift at Mammoth Mtn.
In Colorado during the late elk and deer season, I made the cowboy coffee on the fire poured it into my plastic coffee cup sitting atop the ice chest. The hot coffee cracked the plastic halfway round the bottom of the cup and coffee leaked out, coffee froze on the side of the ice chest before it reached the ground. Two coldest time I can recall ever being in.