By Alex Beresford - ITV Weather Presenter
It's a warm and muggy start for many this Thursday morning and the sun is already feeling strong. Across much of England, Wales, and Northern Ireland there will be plenty of fine weather. In parts of Scotland cloudier conditions will block out the summer sunshine. There will also be some outbreaks of rain as well.
The heat will build quickly today and this afternoon, most parts of the British Isles will see temperatures in the twenties. The further southeast you are the hotter it will be. London could well reach 29C/30C with areas close by not far off.
The humidity is high, making it feel uncomfortable for many, especially if you have difficulty breathing.
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