What breed are they? If they are a primitive then they won't put on any condition through the worst of the winter, but they should be better than cond score 2 at this time of year, heading into the bad weather, whatever breed they are. You might accept a cond score of 2 in older ewes at the end if lambing, but not hoggs at the end of summer. I agree with the FEC and worming in case that's the problem. If it's not, then please discuss the situation with your vet to sort it before the animals are stressed by the winter. Given their low condition score I would feed them hay over the winter - if they eat it they need it, if they don't then they don't need it. Definitely feed hay if you have heavy snow. We always have winter snow so we offer adlib hay from about Nov but we are in Scotland and high. I think your decision whether or not to feed hay, depends very much on your own specific smallholding conditions, grass availability and stocking rate. Those factors vary from farm to farm as well as from north to south, west to east plus altitude and soil type, rainfall etc. I would expect Suffolk (I assume that's where you are) to be fairly easy ground unless we have another severe or very wet winter. Other's actions on their own land and conditions don't necessarily accord with yours.
If your animals are not primitives, then cond score 2 is a real problem, so please do consult your vet for a workup.