Heatwave: Wales' temperatures soar as holiday getaway begins
Temperatures reached some of the highest this year on the sixth day of the heatwave, with forecasters expecting even hotter weather to come.
The Met Office, whose extreme heat weather warning covers large parts of Wales, said temperatures hit 30C in south Wales on Wednesday.
It comes as millions of holidaymakers are set to hit the roads after swapping foreign holidays for staycations.
Tuesday was the UK's hottest day so far with temperatures hitting 32.2C (90C).
London's Heathrow Airport was the hottest place in the country - beating Sunday's 31.6C (88F) best - while in Wales the mercury has peaked at 30.9C (88F) in Usk on Tuesday and Cardiff on Monday.
Emergency services are under pressure due to the heat with the Welsh Ambulance Service declaring an "incident" due to "extreme pressure" on Monday evening with demand overtaking capacity as they are dealing with 2,000 999 calls per day.
An extra 160 spaces are being made available at Pontypridd's National Lido of Wales, Lido Ponty, for Friday's sessions.
More than 5,000 spaces were not enough for those seeking to cool off in the water, with demand for spaces being extremely high all season.
As some cooled off, others reached boiling point, as volunteer coastguards at West Shore, Llandudno, reported being verbally abused by people as they were trying to rescue them from the incoming tide.
The Llandudno coastguard posted on Facebook: "Most people were unaware the danger they were in and were happy to take our advice, however we also received some abuse from a small number of people.
"We don't do it for fun, we are there to keep you safe."
Welsh Water urged customers to use water "sensibly" after a billion litres of water was used in one day instead of the usual 800 million litres.
The not-for-profit company said water demand had increased in tourist hotspots - such as Pembrokeshire - by up to 20%.
Chief executive Peter Perry said: "We just ask people to use water sensibly.
"We've been planning for some time because we knew there was going to be a big staycation influx into Wales this year."
One top doctor has warned that most hospitals across Wales are "under extreme strain" and were at capacity most of the time.
"We see in the hot weather a lot of conditions deteriorate, certainly respiratory conditions, and heart conditions, they are the two most that we see presenting," Dr Mark Poulden, Morriston Hospital's clinical director of emergency medicine told BBC Radio Wales.
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Doctors have also advised parents to encourage children to play in the shade as much as possible, wear hats and long sleeves, and apply regular applications of sun cream to the skin.
But Saturday and Sunday will see a change with a yellow weather warning in place for much of Wales with "heavy, thundery showers likely".
It comes as the RAC has warned Wednesday could be be the busiest day on the UK roads with 2.6 million leisure trips, followed by 2.3 million on Friday.
Traffic data expert Inrix has warned delays on the roads could be up to a third longer than normal July traffic as people holiday in the UK due to foreign holiday travel restrictions during the pandemic.
Wales is also expected to be one of the UK's most popular destinations with an RAC survey suggesting 11% of people heading to Welsh destinations - with the West Country and Scotland ahead of Wales as the most popular places to go.
How hot will it be on Wednesday?
Although temperatures did not set records on Wednesday - the highest temperature ever recorded in Wales was 35.2C at Hawarden Bridge in Flintshire on 2 August 1990 - the Met Office said Thursday could be hotter again.
Forecasters had predicted temperatures of 30C (86F) across southern and western England and 25C (77F) in Belfast.
The Met Office's extreme amber heat warning remains in place for much of Wales, central and southern England and Northern Ireland until Thursday, although scattered thunderstorms and flood warnings are in place in parts of eastern England.
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The Environment Agency has some flood alerts - meaning flooding is possible - in place throughout parts of London, Nottinghamshire and Derbyshire.
Analysis from BBC weather presenter Sue Charles
We're into heatwave conditions for most of Wales. The Met Office's new warning for extreme heat means we need to be wary of impacts such as heatstroke and sunburn as well as the effect on infrastructure and public transport.
A ridge of high pressure has been building over the UK over the past days, which is why it's been getting increasingly warmer.
On Wednesday we'll see a mild start with a little morning mist and patchy cloud but that will soon burn away leading to temperatures in the high 20s and low 30s.
Thursday and Friday will continue sunny and dry too, with just some patchy high cloud possible - and very warm again.
But could it all be over by the weekend? It does look like we could see the hot spell breaking down, with thundery showers pushing up from the south west on Friday.
Watch this space - that beer garden booked for the weekend may need a rethink.
How can you protect your child from the sun?
- Spend time in the shade during the sunniest part of the day when the sun is at its strongest, which is usually between 11:00 BST and 15:00 in the summer months.
- Avoid direct sun exposure for babies and very young children.
- When it is not possible to stay out of the sun, keeping yourself well covered, with a hat, T-shirt, and sunglasses can give you additional protection. You can buy specialist children's sun protection clothing as well.
- Apply sunscreen liberally to exposed areas of skin. Re-apply every two hours and straight after swimming or towelling to maintain protection.
* Source: The Welsh Centre for Burns and Plastic Surgery
What will the weather be like this weekend?
The Met Office has issued a yellow weather warning for Saturday and Sunday but this time for rain, covering 19 of the 22 local authority areas in Wales.
Conwy, Denbighshire and the Isle of Anglesey are the only areas not included.
Heavy, thundery showers are likely, particularly on Sunday when these could be widespread and locally torrential, according to the Met Office.
Lightning and hail are also expected and there could be rainfall of up to 100mm (4in) in some areas, with a chance of flooding.
When is the busiest day for travelling this summer?
Traffic data analysts said the worst days for traffic could be Wednesday and Friday, with typical congestion pinch points being up to a third busier than normal.
Inrix said roads to watch for jams included parts of the M25 around London, the A303 in Wiltshire, the M1 in the East Midlands and the M4 around the Brynglas Tunnels at Newport.
Experts also said to look out for hotspots including the M5 through Somerset and Devon and roads leading to other places such as the Lake District and the south coast.
The RAC predicted an "unprecedented summer" on the UK roads, saying more than 29 million staycations were planned, 16 million of these in the school holidays alone.
"We seem to have all the elements of a perfect storm on the UK's roads this summer," RAC spokesman Simon Williams said.
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"With millions of drivers having already planned their staycation trips, plus the very real prospect of huge numbers more booking last minute if their foreign travel plans end in tatters because of Covid travel restrictions.
"After the hot weather last weekend, the scene is really set for an incredibly busy few weeks on the country's roads, whether that's on motorways or on smaller, minor routes that take people to popular tourist destinations by the coast or in the countryside."
The heat has led to reports of melting tar on the roads, including on the A478 between Kilgetty and Narberth in Pembrokeshire.
How does the heat affect your train ride?
Commuters and passengers have been warned of possible delays on the trains due to reduced speeds on some services because the hot weather can cause tracks to warp and buckle.
"There are some train speeds that have to be reduced just to make sure we're travelling safely in case there are buckles on the infrastructure, and that does have a knock-on effect on the timetable," said Transport for Wales safety and sustainability director Leyton Powell.
"That does mean that we do have some cancellations so we make sure [the trains are] safe to continue."
In terms of passenger comfort, Transport for Wales said they were ensuring air conditioning systems were working, asking people to open windows where possible and providing water and fluids as well as asking people to come prepared.
"What we will ask people....is to plan that journey," added Mr Powell.
"Not just to where you're going but that essential travel back home - don't wait like everyone else until those last journeys where it is likely to be more crowded."
What's the best way to stay cool in the heatwave?
For Sian Richardson, founder of the Bluetits Chill open water swimming group, the heatwave makes her usual swim in St David's in Pembrokeshire seem like it is happening in the Mediterranean.
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"It's around 17 degrees at the moment. It's just incredible for us because it can go down to 6C in the winter and we swim all the year round," she told BBC Radio Wales.
"We love the winter, we love the cold water but it's much more about quick dips, screaming and getting in, getting out, wrapping up, drinking coffee.
"This is all calmer. It's about really wanting to get in because the water is so delightful. Particularly at the moment because it's so hot we're all rushing to get in, then we're lounging about on the beach, drinking coffee and saying isn't it amazing?
"It's so hot here that it is cooling off, and we're all saying, gosh it's like the Mediterranean it's got that lovely holiday feel to it when you go on holiday and the sea is flat."