Forecasters are predicting thunder, lightning and flooding as a yellow weather warning comes into force across the United Kingdom.
The Met Office has implemented the warning for Scotland and Northern Ireland until 11:59 pm on Monday and 11:59 pm for England and Wales on Tuesday, after a change in air pressure led to dramatic showers.
Power cuts, delays and train and bus cancellations are predicted, while spray and sudden flooding could lead to difficult driving conditions for motorists.
Moreover, south-west and south-east England also face a third day of yellow warnings on Wednesday, until 11:59 pm, as the rain eases elsewhere.
Greg Dewhurst, a meteorologist at the Met Office, told the PA news agency: "We'll start off quite humid, particularly across the south and the east of the UK, with thundery showers and sunny spells, but it will gradually become cooler and fresher as the week goes on.
"First half of the week, we're looking at some heavy downpours and thunderstorms developing. You can see that sort of transition coming in from the north, it's day by day. It's still hot, we're looking at highs around 31C, possibly 32C, and then it starts to come down.
"As we head towards Tuesday, temperatures are around 26C or 27C. Wednesday and Thursday will be the mid-20s.
"So probably tomorrow is the last day where we'll see temperatures above 30C for the rest of the week."
Drivers have been urged to take care after predictions of flash flooding.
Here's everything you need to know about yellow thunderstorm warnings.
According to meteorologist Siobhan Ryan: "A status yellow weather alert is given to warn those at risk from certain weather because of their location and/or their activity. It advises these people to take preventative action. Expected weather conditions in a status yellow alert do not pose an immediate risk to the general population."
According to the Met Office, yellow weather warnings suggest people should "be aware". On the Met Office website, it outlines a yellow weather warning will be issued when the weather will cause "Low-level impacts, including some disruption to travel in a few places."
It adds: "Many people may be able to continue with their daily routine, but there will be some that will be directly impacted and so it is important to assess if you could be affected.
"Other yellow warnings are issued when the weather could bring much more severe impacts to the majority of people but the certainty of those impacts occurring is much lower.
"It is important to read the content of yellow warnings to determine which weather situation is being covered by the yellow warning."
In terms of what to expect, the Met Office has said:
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