Met office
UK Outlook for Saturday 1 Dec 2018 to Monday 10 Dec 2018:
Unsettled weather prevails throughout the weekend, with showers or longer spells of rain albeit with some bright or sunny spells in between. It will often be windy, with a risk of gales, with temperatures close to or a little above average. The changeable and at times unsettled weather is likely throughout the following week, with spells of occasionally heavy rain accompanied by brisk winds, interspersed by brighter more showery conditions. Towards the end of this period there may be a transition towards more settled conditions in the south, with lighter winds and more in the way of drier weather developing. Temperatures should initially be milder than average, but are likely to trend downwards by the end of the period with a greater chance of overnight fog and frost.
UK Outlook for Tuesday 11 Dec 2018 to Tuesday 25 Dec 2018:
At the start of this period settled conditions should have developed across the UK, bringing some drier weather and lighter winds but also an increased likelihood of fog and overnight frost. However the second half of December will probably see a gradual return to breezier and much more unsettled conditions, with further spells of rain and strong winds, particularly in the north and northwest where there may be some hill snow. Temperatures should initially be below average, before trending back to normal or milder than average by the end of the period.
https://www.metoffice.gov.uk/public/weather/forecast