A yellow-level thunderstorm warning has been issued by the Met Office as Britons are advised to brace for heavy rain and damage from lightning strikes.
The warning remains in place until 9pm this evening, (Monday, May 8) for part of Scotland and the whole of Northern Ireland.
Those in affected areas have been warned of flooding and possible hail.
The Met Office said people should expect: "Probably some damage to a few buildings and structures from lightning strikes.
The Met Office said Britons should expect possible damage to buildings and structures from lightning strikes
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"Some flooding of a few homes and businesses likely, leading to some damage to buildings or structures.
"There is a good chance driving conditions will be affected by spray, standing water and/or hail, leading to longer journey times by car and bus.
"Delays to train services are possible. Some short term loss of power and other services is likely."
The heaviest showers are most likely in the east of Northern Ireland with a total of 30-40mm of rain predicted to hit over several hours.
The Met Office explained that heavy rain are expected to develop in Northern Ireland across the afternoon.
"These may turn heavy and thundery at times, with a risk of hail," the warning states.
Hail is also possible across Scotland, with heavy rain expected to move eastwards this evening.
"Rainfall totals of 15 to 30 mm is possible in an hour or two in a few places," a Met Office spokesperson added.
The warning remains in place until 9pm this evening, (Monday, May 8)
Met Office
Elsewhere, heavy cloud and rain is expected in the east of England later today.
According to the Met Office, the UK will see: "Scattered heavy showers clearing east across northern areas with clear spells and a few fog patches in the northwest. Elsewhere, rain clearing slowly east but remaining rather cloudy. Mild."
Temperatures are expected to hit 19C in Northern Ireland and the east of England, while London and the Midlands should see highs of 17C.
