UK has hottest July day on record

The temperature soared to 36.7C at Heathrow airport in west London on Wednesday afternoon, making it the hottest day of the year so far and the hottest July day on record in the UK, according to the Met Office.

As forecast a few days ago, a plume of heat and humidity with origins from north Africa has moved up through Iberia, giving many of us our first proper burst of summer heat.

Whilst the highest temperatures recorded in the UK up to lunchtime on Wednesday have been in south east England, temperatures have reached the mid to upper 20s across Wales and Scotland.

Northern Ireland hasn’t been as hot as other places, but the temperature still reached 21C in Belfast by 9am.

Top temperatures by lunchtime

Northolt (NW London) 34.5C

Cambridge 30C

Nottingham 30C

Manchester 29C

Birmingham 29C

Norwich 29C

Trawscoed 26C

Aviemore 29C

Belfast 24C

It's the hottest July day on record with 36.7 °C recorded so far at Heathrow #hottestdayoftheyear pic.twitter.com/KRsarsvg7n

— Met Office (@metoffice) July 1, 2015

Temperatures are still expected to reach 34C, locally 35C, across south east England this afternoon, although the cloud is now building, which means that temperatures are levelling off.

Thunderstorms expected

Although a lot of attention has been given to the heat, it is important not to forget that some isolated severe thunderstorms are expected across Wales, northern England, southern Scotland and perhaps parts of the Midlands into Wednesday evening.

The building heat and humidity has injected a significant amount of potential energy into the atmosphere, and if released, will give some thunderstorms.

As a result, the Met Office has issued a yellow “be aware” warning for north east Wales, northern England and southern Scotland, with frequent lightning, pea-size hail and gusty winds possible locally.

How long will the heat last?

The spell of hot weather will wax and wane over the coming days, with temperatures dropping on Thursday, before the heat surges back across England and Wales on Friday and Saturday.

The hot weather finally clears eastwards on Sunday, with temperatures returning close to average.

As well as the sunshine and heat, hay fever sufferers will have to contend with high or very high grass pollen levels across much of the country.

Don’t forget, you can get the latest forecast on the Channel 4 Weather website. If you take any interesting weather pictures, you can send them to me on Twitter – @liamdutton