Swathes of the UK will be hit with thunderstorms today as the Met Office issued a yellow weather warning.
In an update on Friday morning, the Met Office said northern England and southern Scotland could expect heavy rain, lightning and hail.
The warning lasts from 1pm to 10pm and is in place from Hull up to Edinburgh and across central and eastern regions.
The Met Office also warned that hay fever sufferers should also expect a difficult day.
What to expect
The Met said flooding or lightning strikes could lead to delays and cancellations for train and bus services. Driving conditions would be difficult while there is also a slight chance of power cuts.
The update said: :While many places in the warning area will remain dry, heavy showers and thunderstorms will develop today, becoming most frequent from mid-afternoon and lasting into the evening in places.
"Where these occur they are likely to produce some locally torrential rain with 20-30 mm possible in one or two hours, and will likely be accompanied by hail in a few places.
Glastonbury Festival-goers are being told to expect a wet weekend – with showers forecast on Friday, Saturday, and Sunday.
The Met Office is predicting rain will hit the festival mid to late afternoon on Friday before easing off into the evening.
However, despite the respite from rain overnight, there is a risk of heavy downpours on Saturday and some showers on Sunday afternoon.
Senior Met Office meteorologist Rachel Ayers said: “A band of rain will push across Northern Ireland, Wales and southwest England through the afternoon, reaching Glastonbury mid to late afternoon, bringing cooler and breezier conditions.
“Showers will ease into Friday night and the band of rain will continue north-eastwards bringing some heavy bursts of rain at times.”
On Saturday, the band of rain will weaken but showers will break out to the west and south west.
Ms Ayres said some “could be locally heavy with a risk of local thunderstorms, especially in the south west, therefore risk of some heavy showers for Glastonbury.”
Hay fever alert
The Met Office said pollen levels will remain high or very high for much of the country.
UV levels will be slightly lower than of late thanks to the increase in cloud but will still be high in the south and east