Temperatures will be on the rise into the weekend for some, with an increasing chance of thundery downpours of rain.
On Friday, low-pressure will be positioned to the west of Scotland, continuing a theme of unsettled weather to much of Scotland as well Northern Ireland. However, further south, temperatures will start building on Friday, and could reach 30°C in some isolated spots in the east and southeast.
Met Office deputy chief meteorologist Dan Harris said: “Temperatures will be on the rise from Friday, as a plume of very warm air drifts across the UK from the south.
“Parts of east and southeast England may reach 29 or 30ºC on Friday, with mid-twenties more widely across England and Wales.
“By Saturday, this heat will have extended further north, with parts of Scotland also reaching the mid to high twenties, and again around 30ºC or perhaps even a touch higher for inland parts of eastern England.
“In addition, temperatures overnight will remain high, especially in towns and cities, which will make for an uncomfortably warm night for some.”
Dr Agostinho Sousa, head of extreme events and health protection at UKHSA, said: “This weekend it’s important that everyone takes sensible precautions while enjoying the sun.
“The forecasted high temperatures are expected to be short-lived but could primarily impact those over the age of 65 or those with pre-existing health conditions.
“If you have friends, family or neighbours who are more vulnerable, it is important to check in on them and ensure they are aware of the forecasts and are following the necessary advice.”
The heat will be relatively short-lived, with a thundery breakdown arriving in south-western areas on Saturday courtesy of the low pressure out to the west.
This breakdown will spread northeast through the day and could be heavy in places, with the possibility of associated hail and gusty winds.
Dan Harris continued: “Despite the warm start to the weekend weather for most, we expect a steady transition back to cooler and more unsettled weather with the development of some intense thundery downpours.
“Whilst we have high confidence in the general trends, there remains sufficient uncertainty to preclude us from being able to pin down the most likely locations of the most intense and potentially impactful thunderstorms.
“The main message at the moment is to be aware of the potential for heavy downpours with lightning, hail and gusty winds, so keep in touch with the latest forecasts.
“Warnings may be issued in due course, should confidence increase. However, the vast majority of places will avoid the worst conditions.”
With some potentially disruptive thunderstorms on Saturday, travel conditions could be impacted.
Rod Dennis from RAC said: “Driving conditions will rapidly deteriorate wherever these thundery showers break out – one moment the road will be dry, the next drivers will be faced with heavy rain, hail and potentially gusty winds as well. It’s therefore crucial drivers reduce their speed accordingly, leaving a larger gap between themselves and the vehicle in front.
“It’s also important to ensure car headlights and taillights are switched on – but not fog lights as these risk dazzling other drivers.”
The outlook for early next week is for unsettled, fresh conditions to continue, with periods of showers and rain, especially for those in western areas.
Any drier spells are more likely further to the east, though Tuesday could be a widely rainy day.