If I understand what you're saying, it is that there's little wind, not much sun and it's extremely cold in say, North Dakota, so fossil fuels are cheaper there? Seems to be about a 10 mph avg wind speed [1] and sunny about half the time in daylight hours in winter [2]
So how do you handle peak periods but it happens to only be a low wind generation day? Just tell everybody brownouts are in effect? The only reason that happens in enormous cities like LA, SF, and Austin TX is because they have way too many people drawing power. The grid can't be built faster than people can move in.
In terms of electricity generation, this is why batteries are a monumental step towards making green energy feasible. It accounts for these peak periods, capitalizes off of them, then reuses the stored energy when energy generation is low.
I'm not saying we shouldn't have green energy. I'm saying it's not feasible yet. You're damn well sure it's not feasible for {insert major metropolitan area here}.
The upper midwest has comparable climate to Russia. You know, the Russia both Napolean and Hitler invaded. It's not bad right now, but on occasion we get -10F weather. I know southerners think it's the worst but it's really not. Snow and ice is a bigger bitch to deal with than the temp.
[1] https://www.ndsu.edu/climate/North%20Dakota%20Data/Yearly%20...
[2] http://www.bismarck.climatemps.com/sunlight.php