The most intense heat in the UK on Friday is likely to be in south eastern parts of England, but temperatures could reach highs of 30°C in Wales. The Met Office says that many parts of the southern half of the UK are likely to exceed 30°C and may even reach 34°C in some places, by Friday.
BBC weather forecaster Simon King says: "If we get to 34°C - a good possibility - it'll be only the second time on record we've had a temperature so high before the summer solstice on June 21." The hottest on record in Wales was in June 2000, when temperatures hit 33.7°C in Machynlleth.
The settled conditions are allowing temperatures to build day-on-day with the hottest temperatures expected to be reached by Friday for many. For the weather forecast for Thursday, click here.
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Met Office deputy chief meteorologist Jason Kelly said: “The heat is a result of a mix of home-grown warming due to a high pressure over the southern half of the UK, as well as a south westerly airflow bringing warm air, which has been over continent through the week, across the country.”
“This is the first spell of hot weather this year and it is unusual for temperatures to exceed these values in June. Some areas may see warm nights with minimum temperatures expected to be in the high teens or even low 20Cs overnight, especially in urban areas such as London.”
The Met Office forecast for Wales on Friday says: "Hot for many with intervals of strong sunshine. Slightly breezier than of late but feeling humid throughout. Cooler and cloudier along southern and western coasts. Maximum temperature 30°C."
Here are the top temperatures forecast for parts of Wales on Friday (June 17) from the Met Officer weather maps:
Cardiff 26°C
Swansea 21°C
Wrexham 27°C
Bangor 21°C
Aberystwyth 22°C
Newport 26°C
Brecon 25°C
Tenby 18°C
The temperatures don't look set to be high enough for long enough in Wales to class it as a heatwave, although a heat warning has been issued for parts of England.
And the warm weather is not going to last long as the Met Office forecast for the weather in Wales over the weekend is: "Feeling cooler for all into the weekend but rather cloudy with the risk of some heavy showers. Turning drier for next week."
