dashboard has been going dark?

My car’s dashboard has been going dark recently then popping back on it’ll do that then sometimes almost every light except my battery light comes on. My car has never done this before, only after the snowstorm we had. That very next morning as I was on the highway it did that but the engine stayed running even before and after the dash came back on no battery lights or anything is being illuminated and it is still doing it, my mechanic believes it’s the super cold weather but this is sketchy can someone explain this phenomenon again no lights are on the dash now it just only goes dark then comes back on sometimes the dash gets really dim like its bout to cut out but I turn my car off when that happens and turn it back on and it’s back to normal.