I use both whole milk or 2% reduced fat milk regularly.
If the weather is too chill then preheat the oven and keep the milk to set.
Better to use stainless steel vessels or glass bowls.
Try to add more little more culture for winter (say 2 tsp) and in summer you may not need more than 1.5 tsp.
And you may use 1 or 2 whole green chili's to set curd very quick.