LGBT+ pride events in Chester, Plymouth and Milton Keynes have been postponed.
The first day of Blackpool Air Show, held on Saturday, and the London Wildlife Festival, scheduled for the weekend, were cancelled amid concerns over windy conditions.
Dean Hall, a Met Office forecaster, described the weekend weather as a “messy picture”.
He said: “We have bright, sunny spells with blustery showers in England and Wales and heavy, slow moving, thundery downfalls developing with a risk of hail.
“There is a thunderstorm warning on Saturday which extends across eastern central Scotland through northern England.