London Heatwave: Latest Updates

London Heatwave: Latest Updates
It's so hot that heading to the park is probably not a good idea. Image: Shutterstock

You may have heard... it's going to get fairly warm in London this week.

The capital is forecast a heatwave, with predictions of the highest temperatures ever seen in this part of the world. The message from official channels is that this is not just a few sunny days — it's extreme, possibly unprecedented, weather. We'll all need to take extra precautions to keep ourselves and each other safe.

We'll keep this page updated with what's happening in London as the situation progresses. See below for latest updates, and below that for further information.

Latest updates

Red weather heat warning on an orange screen at Waterloo station
Image Laura Reynolds/Londonist

5.25pm: London Ambulance Service says it is answering 400 calls an hour as a result of the extreme heat. Gold Commander Peter Rhodes asks people to only call 999 in a life-threatening emergency, and to take precautions such as staying out of the sun and drinking plenty of water

4.30pm: Dawn Butler, MP for Brent Central, has said that there are currently eight serious fires in Wembley. The location of all of these fires isn't known, but it includes a blaze at The Broadway, Forty Avenue, reported to be in an outbuilding. London Fire Brigade also dealt with a fire at a shop in Eltham this afternoon.

3.25pm: London Fire Brigade has declared a major incident, as it battles several 'significant' fires around the capital simultaneously. In addition to the grass fires in Croydon and Upminster (details below), another fire has broken out in a residential area in Wennington, near Rainham. Meanwhile, Kent Fire & Rescue are battling a field fire near Dartford, on the London-Kent border, with flames seen alongside the A2.

1.20pm: London Fire Brigade is currently tackling grass fires in at least two locations in the capital. Oaks Road and Chapel View in Croydon both have firefighters in attendance due to woodland fires, while 30 engines and around 175 firefighters are at a large grass fire on Pea Lane in Upminster, with LFB working with crews from Essex on this one. It's located next to the M25, with smoke blowing over the motorway and is affecting C2C trains as the fire is lineside between Ockendon and Upminster. Though the cause of these fires hasn't been identified, here's a reminder to take care when extinguishing barbecues and cigarettes, and not leave any glass lying around, to avoid more fires while the grass is so dry.

1pm: It's official — London is having its hottest day on record. A temperature of 40.2°c has been recorded at Heathrow according to the Met Office, higher than London's previous highest recorded temperature of 38.1°c, which was also recorded at Heathrow, back in 2003. Today's figure was recorded at 12.50pm, and may climb higher until today's temperature peaks.

10.45am: Relief may be on the way, as the Met Office has issued a Yellow warning for thunderstorms across London and the South East. It's in force tomorrow (Wednesday) between 1pm and 9pm, with heavy showers and thunderstorms expected, and the chance of some sudden flooding. It was this time last year when London saw heavy rain causing flash flooding that blocked roads and closed tube stations.

Tuesday, 8.20am: A reminder that many train operating companies are operating blanket Do Not Travel warnings today. Services are likely to be severely disrupted, or cancelled altogether, with no alternative transport provided, and there's no guarantee that you'll be able to reach your intended destination. LNER and  Southern are among the companies specifically warning customers not to travel, though all operators are likely to be affected to some extent. TfL is still advising customers to only travel if essential.

Meanwhile, photographer and Twitter user Simon Lamrock has shared some images taken on a thermal imaging camera, showing how hot buildings and buses in London got yesterday:

9pm: Here’s a biggy. No Thameslink trains will be running north of London on Tuesday (I.e. nothing to Luton, Bedford, St Albans, Cambridge, Peterborough or Stevenage). Routes south are also badly affected, with no trains to Sutton and reduced services elsewhere. No replacement buses are running either.

4.50pm: The Mayor reminds us that today's heat is causing a secondary problem: increased air pollution.

4.47pm: Luton Airport has closed its runway "for at least an hour" to repair a defect caused by the heat. Planes are being diverted elsewhere and departures are, of course, delayed.

2.28pm: And in news that will surprise nobody...

Though, thinking about it, isn't the cable car always suspended, by definition?

12.01pm: We don't mean to be alarmist about this, but there are now suggestions that temperatures could reach as high as 43 degrees tomorrow, according to the Telegraph who've spoken to the Met Office. That's at the extreme end of meteorological models, though.

10.00am: The East Coast Mainline between London and York will close entirely on Tuesday 19 July, as it struggles to maintain a service in the heat.

9.40am: Severe delays and suspensions are now reported on several London underground lines, including the Bakerloo, Central and District. The Hammersmith and City line is completely suspended. TfL live tube updates.

9.05am: Over at the London Aquarium, the penguins are keeping cool by pecking away at ice buckets and "ice cakes made of fish", according to a press release.

9am: There's a reduced service on many rail lines this morning, as operators anticipate difficult conditions on the rails. Services that are running are subject to delays, as the heat warps the track and other equipment.

Met Office issues first ever Red warning for heat

The UK's national meteorological service, the Met Office, has issued its first ever Red warning for exceptional heat. It's expected to reach 38-40°c (100-104°F) in London on Monday and Tuesday next week. To date, the highest temperature ever recorded in the UK was 38.7°c in Cambridge in 2019. London's record is 38.1°c, recorded at Heathrow in 2003.

A Red warning means that dangerous weather is expected, and you should take action to keep yourself and others safe.

On Friday morning, Met Office Chief Meteorologist Paul Gundersen, said:

Exceptional, perhaps record-breaking temperatures are likely early next week, quite widely across the Red warning area on Monday, and focussed a little more east and north on Tuesday. Currently there is a 50% chance we could see temperatures top 40°C and 80% we will see a new maximum temperature reached.

Stay up to date with the latest warnings and forecasts on the Met Office website.

Scorched grass in London in the July 2018 heatwave. Photo Mark Ramsay via creative commons

Heatwave health tips

That Met Office warning comes hand in hand with a Level 4 (Emergency level) heat health warning. This means that the heat is likely to be so severe, it will affect not just groups of people usually affected by severe weather, (such as the elderly and children), but otherwise-healthy people could also be affected.

The government's Heatwave Plan for England offers advice on how to keep yourself and those around you safe. The NHS also has some tips (though note this page is directed at all heatwaves, rather than specifically at the extreme heatwave we're seeing this week). Top tips include:

  • Drink plenty of fluids
  • Avoid excess alcohol
  • Stay out of direct sun where possible, particularly between 11am and 3pm, and close curtains on rooms facing the sun to keep them cool during the day
  • Apply sunscreen and wear a hat when outside
  • Slow down, avoid exercise in the peak of the heat
  • Don't leave people or animals in parked cars

London transport heatwave updates

Expect delays if travelling by train. Photo: Divyansh Jain via Unsplash

TfL is advising passenger to only travel if absolutely essential on Monday and Tuesday, and is warning of speed restrictions on both the tube and rail network, with the result of a reduced service and longer journey times. There's also advice to only use the Santander Cycles for short journeys, and only if absolutely essential, to avoid strenuous activity.

National Rail is advising of severe disruption to train services on the hottest days across England and Wales, due to the need to run trains at lower speeds than normal. This is because of the possibility of extreme heat causing damage to the tracks or overhead wires. There are no revised timetables in place — it's just a case of checking on the day whether your service is running, and allowing extra time to complete your journey. Network Rail advises that you only travel if absolutely necessary.

National Highways has some advice for motorists in the extreme heat.

What's closed in London during the heatwave?

It's possible that some venues, attractions and services may close during the hot weather, for the safety of staff and the general public. If you have plans on Sunday-Tuesday, check with wherever you're heading before you set off, to make sure it's opening as usual.

ZSL London Zoo has said it will remain open, but there may be some changes:

The Great City Race, a 5km run through the City of London which was due to take place on Tuesday, has been postponed.

Conversely, Hammersmith Bridge is being kept open (to pedestrians and cyclists), by being wrapped in insulating foil to keep it cool in the hot weather. In 2018, micro-fractures in its pedestals widened during a heatwave. It's hoped that it will stay open throughout this year's hot weather, but if any of its chains reach 18C, the bridge will have to shut for safety reasons.

Reducing fire risks

The Royal Parks has reminded people not to barbecue in its parks, and to avoid leaving glass out in the sun to avoid the risk of fire:

The City of London, which manages Epping Forest, has similar advice.

Staying cool in London in a heatwave

Ooh, yes please. Image: Shutterstock

So what can you do to keep cool as the temperatures rise? The best advice is to stay indoors, somewhere air conditioned if at all possible, and avoid going out in the sun during the hottest part of the day.

We've put together a guide to keeping cool in London in the summer heatwave, covering everything from air-conditioned tube routes to the best beer gardens (though stay under an umbrella, and avoid excessive alcohol!) to fountains which you can splash around in to cool off, and of course, plenty of places to go swimming (though they'll be VERY busy).

The Mayor of London's office has compiled a Cool Spaces map, showing both indoor and outdoor spaces where you can take respite on a hot day, such as areas with plenty of tree canopy cover providing shade.

There's also Refill London, which shows you where you can refill your water bottle for free, helping Londoners to keep hydrated and avoid unnecessary plastic usage.

Severe Weather Emergency Protocols have also been activated to help rough sleepers in the heatwave. Measures include local boroughs increasing welfare checks on vulnerable people, and providing them with sunscreen and water — though some may argue that this doesn't go far enough, and that shelters should be opened, as they are in extreme winter weather, to provide rough sleepers with somewhere to seek refuge.


We'll update this page as we have more information on how the heatwave is affecting London — keep checking back for the latest updates.

Last Updated 21 July 2022

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