Record-breaking heat is set to hit parts of the country today as temperatures are predicted to hit 35 °C in Wales.

Parts of England have been given a red weather warning for today, where the temperatures could soar as high as 40 °C. In Wales, an amber weather warning remains in place today (Monday, July 18).

According to the Met Office, this afternoon could see a maximum temperature of 35 °C. Tonight will also remain warm with a minimum temperature of 18 °C, though Tuesday is set to cool.

READ MORE: Met Office issues amber warning for Wrexham and Flintshire as heatwave continues

The unprecedented temperatures may cause disruption throughout the day.

Jake Kelly, spokesman for Network Rail, has warned of travel disruption across the country due to the heatwave, and has warned that services returning to normal on Wednesday “will depend on the damage that the weather does to the infrastructure” over the course of Monday and Tuesday.

Speaking to BBC Radio 4’s Today Programme, Mr Kelly said: “Our advice very strongly to customers in England and Wales today and tomorrow is to only travel if absolutely essential, and to expect a very reduced train service and delays.”

He added: “We haven’t taken any of those decisions lightly, but we’ve not been faced with these exceptional temperatures before.”

READ MORE: Transport for Wales cancel a number of services due to incoming weather warnings

He said: “We’re spending hundreds of millions of pounds a year on making the railway more resilient but ultimately faced with weather like we’ve never faced before, the infrastructure will suffer so we’ve had to put in place arrangements.”

Looking ahead to the rest of the week, Mr Kelly said: “We hope and expect to run a full service on Wednesday and beyond, but that will depend on the damage that the weather does to the infrastructure over the next couple of days. We have lots of plans in place to make sure that we can run.”

People are also being warned to stay cool throughout the day.

READ MORE: Here's how to stay safe and comfortable after Extreme Heat Warning is issued

Deputy chief medical officer Thomas Waite for England has also listed some of the tell-tale signs of heat exhaustion and what can be done to treat the condition.

Dr Waite told GMB: “That combination of fluid loss through sweating and through that hard work through your heart pumping, getting more blood to your skin can lead to a range of symptoms, so you can get sweaty, really quite excessive sweating, cramps, nausea and vomiting and dizziness.

“That’s a set of symptoms called heat exhaustion that’s really quite easily treated.

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“If you see somebody who’s experiencing those symptoms, get them into the cool, get them into the shade, give them some fluid to rehydrate, it can be water, it can be sports drinks or rehydration fluids, and most people will make a good recovery in about 30 minutes or so.”