Well it won't be most the big rides too cold at that time of year. Maybe Nemesis or Oblivion might get away with it
The cold weather is February.
They can operate a lot more in November/December than they can in January/February.
But they spready out the winter maintanance so won't open the whole park. But 15/20 years ago when they did Winter Weekends for hotel guests it used to be Forbidden Valley November/December and X Sector January/February. Then they tried to move to a more family based line-up for winter openings with very few big coasters open.
Bad weather is what stopped the February half term openings though.