Thunderbolts and lightning were very frightening indeed as Dacorum was subject to a surprise storm overnight.
Met Office warnings of an impending heatwave had been announced yesterday, with forecasters suggesting the soaring temperatures would lead to thunderstorms by Saturday.
But the deafening claps of thunder woke up many across the borough a night early.
Impressive flashes of lightning were caught on camera – in some cases using smartphones – by skilled snappers forced out of bed by the natural phenomenon.
Those with particularly ‘striking’ shots shared their images on social media this morning – see a selection of those posted to the Facebook page Hemel Hempstead Remembered in the slideshow above.
The Met Office has issued a yellow weather warning for high temperatures and thunderstorms in the London and South East regions.