As Kent woke today to temperatures already hitting 22C, the Met Office warned of travel disruption and that people's lives could be at risk as temperatures are expected to rise further.

The bureau has issued its first red weather warning for extreme heat as parts of the county are predicted to reach nearly 40C - a new UK record - next week.

The warm weather saw increased demand for water in some parts, with South East Water confirming residents in Challock and Molash have no water due to “continuous hot weather and significantly increased demand for water” putting “significant pressure on our network”.

A bottled water station has been set up at Challock Village Hall.

An emergency Cobra meeting was held today to discuss the heatwave.

Cabinet Office Minister Kit Malthouse warned transport services face “significant disruption” next week due to the heatwave, urging people not to travel.

After chairing the meeting, Mr Malthouse told the BBC: “Obviously the transport providers are messaging people that they should only travel if they really need to on Monday and Tuesday.

“Services are going to be significantly affected. The heat will affect rails, for example, so the trains have to run slower. There may be fewer services. People need to be on their guard for disruption.

“If they don’t have to travel, this may be a moment to work from home.”

Train services could be affected as speed restrictions are introduced to help protect rails from buckling and there will be no turn-up-and-go tickets available on Eurotunnel or the ferries out of Dover.

Southeastern are providing more carriages on busy routes heading for the coast this summer and included Margate, Broadstairs, Folkestone, Herne Bay and Whitstable as their busiest destinations.

A spokesman said: "On really hot days we’ll have a ‘crowdbuster’ train on stand-by between Faversham and Ramsgate, longer weekday trains from Victoria to Ramsgate and there’ll be extra staff on hand to help keep you safe and secure.

"There may be one-way systems and queuing arrangements at the busiest stations, such as Margate and Hastings, so remember to bring a bottle of water and leave plenty of time for your journey."

The train operator has also warned that the heat may force slower speeds on the tracks and a high risk of rails buckling as the steel expands in the heat.

It warned: "When the temperature soars, things really heat up for our infrastructure – metal rails in direct sunshine can be as much as 20°C hotter than air temperature.

"When our monitoring systems tell us that a section of track is likely to expand, we put in place speed restrictions to reduce the chance of rails buckling, so you may find your journey slower than usual.

"We work with Network Rail well in advance to make sure that your railway is ‘hot weather ready’ but speed restrictions are needed where rails are particularly hot, so that trains can move safely along the track."

Motorists are reminded Operation Brock is in place on the M20 while there could also be traffic controls at Brenley Corner, Faversham, to ensure EU-bound HGVs using the M2 are returned to the M20 to re-join the Brock system.

Kent Resilience Forum strategic planning lead Simon Jones said: “It’s going to be a lovely weekend but there are also warnings that we could see some record-breaking temperatures.

“What we would really like people to do if they’re travelling in Kent, either heading off to Europe or visiting one of our many wonderful attractions, is to plan that journey. Take plenty of water with you, plus snacks and any medication and other essential supplies.

"Stay informed, follow the signs and help us to help you get to your destination as quickly and as safely as possible. We thank everyone for their ongoing patience.”

Kent County Council issued a Heat Health Alert on its Twitter feed.

Gravesend, Dartford and parts of Medway all fall under the the red weather warning.

Those planning to soak up the sun's rays in parks or on the coast have been reminded to slap on the sun screen to prevent burning as hospitals brace themselves for a spate of heat-related admissions.

Dog-owners have been warned not to leave their pets locked in cars and those spending a day at the seaside have been told to keep safe.

The RNLI said: "If you're heading to the coast during this heatwave, remember to visit a lifeguarded beach, swim between the red and yellow flags and if you get in trouble in the water float to live."

Transport for London is advising customers to only travel if essential next week.

A spokesman said: "Due to the very high temperatures predicted, temporary speed restrictions will need to be introduced on parts of the Tube and rail network on Monday and Tuesday as a precaution, which will mean a reduced service and could mean journeys take longer than usual.

"Very hot temperatures can affect rails, overhead power lines and signalling equipment. Track temperature checks are continuing to be carried out regularly across the networks to ensure they remain safe and that the track is not at risk of bending or buckling."

It said it was also inspecting the air-conditioning units on Tube trains and buses.

Meteorologists say there is an 80% chance of the mercury topping the UK’s record temperature of 38.7C (101.7F) set in Cambridge in 2019 with the heatwave set to peak on Tuesday.

Temperatures will climb over the weekend with today's temperatures predicted to be around 27C in London, rising to 30C on Sunday.

The UK Health Security Agency has increased its heat health warning from level three to level four which is classed as a national emergency.

Level four is reached when "a heatwave is so severe and/or prolonged that its effects extend outside the health and social care system… at this level, illness and death may occur among the fit and healthy and not just in high-risk groups.”

Met Office spokesman Grahame Madge said: “If people have vulnerable relatives or neighbours, now is the time to make sure they’re putting suitable measures in place to be able to cope with the heat because if the forecast is as we think it will be in the red warning area, then people’s lives are at risk.

“This is a very serious situation.”