Brrrr! It's cold out there (Must be some Torros in the atmosphere?)

Things like this are making me nervous:

In case you were wondering where this beautiful winter weather is going to be, it is the Grand Canyon. And we happen to be hiking into the canyon on...you guessed it...the coldest day of the week! That low of 3 degrees is pretty scary considering we will be sleeping outside. I am counting on the dramatic elevation change, the one that will fry my glutes and most likely make me lose my two big toe nails, to also create a very large temperature differential. Fingers crossed (and hopefully not stuck that way or frostbitten).