Hello and welcome to the RTA forums !

You will not be able to cross he Sierra mountain range during January and will therefore have to head North towards Lake Tahoe or South to Bakersfield to get around them. Yosemite will be in "winter mode" and you could face snow chain restrictions in places, where you will have to have them fitted on your tyres to continue.

You certainly have the time to do the trip quite comfortably but you will need to keep your eye on weather and road conditions as you travel.