Tuesday
Extensive fog in central & northern areas first thing, and is likely to persist most of the day in low-lying regions, particularly Vale of York. Thickening cloud and an increasing breeze across southern Britain should break up the low level murk. Patchy rain develops for the south-west, turning persistent by afternoon. Some sunshine to the north of high ground in Scotland & Wales. Temperatures 10C in fog, to 16C in sunny areas.
Tuesday night
Low cloud and drizzly rain spreads north across England and Wales during the evening and overnight. Extensive hill fog, but less low level fog than recent nights. Mostly light winds, but a brisk south-easterly breeze on the south coast. Staying mild for most areas, at 7 to 11C, but where skies stay clear in northern Scotland, there may be slight frost, lows close to freezing some glens.
Wednesday
A rather murky day for many areas, with extensive cloud and hill fog. Weak fronts moving up from the south produce intermittent drizzly rain. Some heavier bursts threaten south-east England, moving north across East Anglia by early afternoon. Perhaps brighter skies developing for Wales & the south-west. Light winds most areas, but suddenly strong a gusty in south-east. Temperatures feeling cool in rain, most areas around 11 to 14C.
Thursday
Fronts moving in from the Atlantic bring rain to Ireland & western Britain, becoming persistent over many hours, heaviest across south facing hills of Wales, Cumbria & south-west Scotland. A bright start is likely for eastern Britain, before clouds thicken from the west. Patchy rain moving into the Midlands & the east later in the day. A brisk southerly breeze, particularly in western areas. Generally mild, highs 12 to 16C.