Hottest day of the year to spark thunderstorms

1 month ago 56

Dark thundercloud with fork of lightning hitting ground

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Thunderstorms are most frequent during the summer as hot, humid air adds more energy to the atmosphere.

Temperatures have been on the rise over recent days, with the peak of the current hot spell expected today. But for some places, especially in the north, this heat will also bring some big thunderstorms.

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Expected maximum temperatures on Monday

How hot will it get?

Today is likely to be the hottest day of the year so far. The highest temperatures are expected across central and south-east England, with 34 or even 35C likely, probably somewhere in Cambridgeshire, Essex or Norfolk. Elsewhere across England and Wales, highs will typically reach 23 to 28C, whilst Scotland and Northern Ireland will be a fresher 18 to 22C.

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Hot, humid air is flowing in from the south as the jet stream sits to the north of the UK

Why so hot?

The jet stream is sitting to the north of the UK - in part due to the influence of ex-Tropical Storm Debby - allowing hot southerly winds to bring us air originating from southern Europe and North Africa. High pressure close by has meant a few days of clear skies and a day on day build of warmth.

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Thunderstorms will bring the risk of large hail, gusty winds and localised flooding

Where are thunderstorms expected?

We've already seen thundery downpours across Northern Ireland, western Scotland, north-west England and Wales. These will push eastwards through the day, with the greatest risk for the rest of today across Scotland and northern England, where a Met Office yellow thunderstorm warning is in force.

How long will the heat last?

After the peak of heat on Monday, temperatures will start to ease, but we'll have a few more warm, humid days in the south-east. Tuesday could see highs again close to 30C, but by Wednesday, we'll all be back to more typical temperatures for mid-August.

Check the longer range forecast here

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