New Year's Eve starts wet for many places. There is likely to be a band of heavy showers behind the main rain bringing more wet weather before things dry out as we see in the new year. It will still be rather blustery so even though it's relatively mild it won't really feel it.
Some places will be a toucher brighter as clearer spells develop.
As night falls the temperatures will fall away quite quickly, so if you're planning on heading out see in the New Year, then wrap up warm. By midnight it will be mainly dry although there's still a chance of an odd shower left over.
New Year's Day will be dry and bright with a few coastal showers for the north and west and it will feel rather chilly. Temperatures recover a touch midweek but it will be mainly dreary, lots of cloud with outbreaks of light rain.