I think you have a reasonable chance of some light snow both ways. Impossible to quantify how much still. I think that you will be alright on the trains - but take warm clothing just in case! I can look in another couple of days if you like to firm up the forecast.
Katymac - when do you need to know whether you are definitely going? It is some days off yet 9forecast wise) but the latest model run (they do vary a lot!) shows a fair amount on Saturday through sunday. It may well all change by then but......
I have 2 days to get back I can leave between about 8pm on Saturday and anytime on Monday........I suppose (mind you we might have to close/cancel children etc but it might be snowy here so they might not come anyway )
Katymac - that is true at first. By Sunday anywhere could see the snow - and of course even if Blackpool (which tbh it may well not snow - being right on the coast and sea temps still being warmish) you have an awful lot of 'not west' to go through.