8 minutes agoLast updated 8 minutes ago
In the latest edition of Climate Check, we look at why the polar regions are warming so fast and how higher temperatures there can affect the rest of the world.
The weather is set to turn hot in the coming days for some, with a risk of thunderstorms into the beginning of next week.
BBC Weather's Helen Willetts explains the different factors that affect the strength of UV radiation.
Last year was remarkable for high temperatures and severe swings, according to the Met Office.
Millions of people were left without power in the US as the storm swept through the eastern seaboard.
BBC Weather in association with MeteoGroup
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