It will still be winter that time of year...even out on the plains a heavy spring storm could cause a lot of trouble. Up in the high country it will be beautiful. It has been snowing almost every day in the high country.
You will need to have chains onboard and be prepared to put them on or wait out a storm down in Denver in case they put the chain law in effect. You may also want to have a set of chains for your car if you are towing. The highways and streets are kept in good shape but maybe not bare and dry so some snow packed streets or highways are possible.
The grades on I70 aren't too bad but if you aren't used to mountain driving be aware your rig will be a bit oxygen starved. Today's computers in rigs can help but still be prepared to be chugging along.
And for the human aspect...you will feel a bit low on air and energy too. Drink a lot more water than normal and keep movement to a minimum. It takes a few days to get used to the altitude but if you'll only be there a few days you may not get to feeling great until you are about to leave.
Since it will be still very cold in the mountains be sure your rig is winter ready, propane full, have a snow shovel inside, not in the lower bay. In the mountains they count snowfall in feet not inches!
Enjoy your winter outing!