Portsmouth and most of Hampshire under the Met Office's first ever extreme heat warning

Residents are warned they face heat exhaustion and power failures due to the extreme heat, which has seen the city swelter with highs of 29C – hotter than Mumbai and Mexico City.

The weather warning covers much of the south of England and Wales, ranging across Cornwall, Birmingham, most of Hampshire, and the Isle of Wight.

The extreme heat is set to last until the end of Thursday, when temperatures are expected to dip to highs of 23C in Portsmouth.

The Met Office introduced extreme heat warnings were introduced at the start of this month as forecasts predicted a record-breaking heat wave.

The Met Office warning said: ‘The wider population are likely to experience some adverse health effects including sunburn or heat exhaustion – dehydration, nausea, fatigue - and other heat related illnesses

‘More people are likely to visit coastal areas, lakes and rivers leading to an increased risk of water safety incidents

‘An increased chance that some heat-sensitive systems and equipment may fail, leading to power cuts and the loss of other services to some homes and businesses.’

The new warning was brought in after consultations with Public Health England and the UK's other health agencies, with the intention of highlighting the dangers of heatwaves.

England, Scotland, Wales, and Northern Ireland all recorded their hottest day of the year so far over the weekend.

A message from the Editor, Mark Waldron

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