Just looking at google maps has the drive from Vegas to the south rim at 275 miles which will take 3 1/2 to 4 hours. I have only driven that route as far as Boulder Dam, so I cant say for sure.
Temperatures at the Grand Canyon should range from low 40's to low 50's during the day. It will get much colder at night, low 30's to low 20's. You can figure about10 degrees colder than that, for both the high and low, if a cold front comes through.
You definitely want to plan on staying at the canyon long enough to watch a sunset. There are also plenty of short hikes and other things to see. My wife and I spent 3 full days there a couple years ago.
Temperatures at the Grand Canyon should range from low 40's to low 50's during the day. It will get much colder at night, low 30's to low 20's. You can figure about10 degrees colder than that, for both the high and low, if a cold front comes through.
You definitely want to plan on staying at the canyon long enough to watch a sunset. There are also plenty of short hikes and other things to see. My wife and I spent 3 full days there a couple years ago.