Rain and thunder is forecast to hit London this weekend as an extended spell of dry weather in the capital comes to an end, forecasters have said.
London is likely to see “thundery showers” on Saturday despite temperatures hitting a high of 24C, according to the Met Office.
It follows a week of dry, hot weather in the capital with the mercury hovering at around 21C.
Elizabeth Rizzini, of BBC Weather, said: “On Thursday the wind will turn towards the southeast and push warm continental air towards London in time for the weekend.
“Temperatures could rise into the high 20s but watch out for the possibility of thundery showers too.”
Wednesday will see sunny spells across the capital with a few lingering patches of cloud, with the weather expected to remain dry and hot all through Thursday.
Warm sunshine will remain for many on Friday, with the high pressure dominating to give mainly fine and settled weather.
The Met Office said it expects the hottest temperatures of the year so far to be reached by the weekend.
The threshold for a heatwave is different across the UK, but in some areas it is classified as hitting highs of 25C to 28C across a three-day period.
Saturday will be the warmest day, with forecasters expecting it to reach 27C or 28C, with a small chance of it hitting 29C, north of London.
Simon Partridge, forecaster for the Met Office, said: “It will get warmer but there may well be more cloud with heavy, thundery showers mixed in as well.
“There will still be plenty of sunshine around, but it will come with much muggier nights.”
Mr Partridge added: “We continue with showers on Sunday and Monday and it will turn a little bit cooler again.
“Showers over the weekend will become heavy at times, and there’s a risk of a bit of thunder. There will be 10-15mm of rain over the course of two to three hours, which is nothing too significant.”
The highest temperature in the UK so far this year was 25.1C in Porthmadog on Tuesday.
High levels of pollen are expected across the Midlands and south of England, as well as in all of Wales and Northern Ireland until Friday, the weather service said.
Spokesman Grahame Madge said: “We are now getting into grass season. With it being so dry across the UK, it means grasses are able to shed pollen.
“For sufferers, hay fever has been a feature of the last few days and will continue to be a feature for sufferers over the next few days and weeks.
“(Sufferers will) only get a respite when the grass has shed all the available pollen or if we get significant rainfall, which will effectively wash the pollen out of the atmosphere.”
