Summary for all mountain areas

A warm and humid day with extensive low cloud affecting many hills and pulses of thundery rain moving north through the morning followed by further clusters of showers or thunderstorms. Becoming largely dry through the afternoon across Wales as winds veer southwesterly. Best of the cloud breaks will be towards the west coast.

Headline for Yorkshire Dales and North Pennines

Clusters of showers/thunderstorms. Low cloud much of the day.

How windy? (On the summits)

Easterly, 20 to possibly 25mph post dawn. Otherwise, 10-15mph.

Effect of wind on you?

Soon becoming small.

How Wet? (Precipitation and its impact)

Risk thunderstorms.

Low confidence of detail: A swathe of thundery rain from the early hours will push away north, but a threat of further clusters of thundery downpours forming during day.

Cloud on the hills?

Extensive much of the day.

Extensive fog across the hills for much of the day, in some areas from lower slopes. Whilst timing very uncertain, cloud may largely break up across some western hills for a few hours around the middle of the day, before filling in again later from the south.

Chance of cloud free summits?

40%

Sunshine?
Air clarity (below cloud)

Patches of sunshine developing. Murky, visibility reduced considerably by rain, and a general haze at best.

How Cold? (at 700m)

14C, very humid.

And in the valleys

Rising from 15C to a muggy 22C.