The Bank Holiday weekend has brought an unexpected blast of summer heat to UK shores - with temperatures today set to rocket to 30 degrees Celsius - but alas, pasty, pale Brits have been caught out by the last-gasp summer sunshine.

Social media was awash last night with images of sunburn fails, as lobster-red revellers shared photographs of how they'd been stung by the powerful August rays yesterday, which saw parts of the British Isles hotter than Spain.

With Reading Festival, the Notting Hill Carnival and Manchester and Cardiff Pride among the many events bringing thousands outdoors, plenty admitted they underestimated the balmy weather, which looks set to stick around as the hottest Indian Summer in 11 years has been forecast.

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Ouch! One Instagram user, djwptvalhalla_gym, admitted he got caught out by the hot sun while training for a strongman event yesterday...and has red-raw sunburn to prove it

Factor Zero! Sun-bathers shared images of their tanning fails after the mercury soared across Europe including wincing Instagram user Elginthwaites, who admitted she had a very sore bottom after not applying sunscreen

Fair-haired Brits struggled with the scorching weather, with geeky_kat penning on social media: 'I am not made for the sun'

Beach life...UK style: Bigredlovesphotos shows off her red-tinged face after a day at the British seaside

Red necks: After a dismal August in the UK, pale Brits felt safe enough to eschew the sunscreen...but soon regretted it

Speed tanning: The British Moto GP left fans watching in the stands feeling a little pink

One unfortunate lady, who'd clearly donned her bikini and hit the beach, even showed off her rather sore looking derriere, after the sun left its crimson mark on her lower half.

With a pained face and a red behind, Elginthwaites explained her pain via a multitude of hashtags on Instagram including #sorea*** and #cantsitdown.

WHAT IS AN INDIAN SUMMER? The term Indian Summer has long been used to describe an autumnal heatwave. The phrase has its origins with the Native Americans on the east coast of the US, who used to find frequent bursts of hot autumn weather would produce bountiful crops - and was more preferable to work in than during the intense heat of the mid-summer. While some maintain that you can't have an Indian Summer unless you've first had a frost, most are happy to use the term to refer to any unseasonably hot weather from September onwards. Advertisement

She also admitted that she hadn't covered up her skin with sun protection despite donning her bikini.

The extended weekend meant many turned their attentions to festivals, al fresco BBQ dining and simply lying in the sun, and found themselves striped pink by the end of the day.

At Reading Festival, headlined last night by Muse, many said they'd been caught napping when it came to applying sun screen - and paid for it later.

@_nicolealice wrote: 'Had such a good weekend at Reading but my sunburn is sooo peak.'

Elsewhere, on Instagram, Jasmin Clayton took to Instagram to show off her pink shoulder blades after just a short blast of sunshine, writing: 'When you're pale and sit in the English sun for 20 minutes'.

Instagrammer LJC290793 posted a photo of her back, comparing it to pink and white sweets

'When you're pale and sit in the English sun for 20minutes' Jasmin Clayton took to Instagram to show off her pink shoulder blades after just a short blast of sunshine

Twitter user @samjamestweet blamed the forecasters for his scarlet-hued neck, saying: 'It won't be that warm they said...'

On Twitter, user @Samjamestweet had beef with the meteologists, saying: 'It won't be that warm they said...' before showing off a bright red neck line.

Meanwhile, back on social media, there were red noses, red necks, shoulder blades ablaze with the sun's marks - and lots of references to being 'British' in the sunshine.

On Instagram, Sophie A Morrison bemoaned the advice of friends, after they said she wouldn't get burnt - and she ended up with furious pink shoulders.

Despite a largely dreary August, the grey skies have parted and today is set to be the hottest August Bank Holiday on record.

Hot winds from Europe have gifted this late summer heatwave to Britain, with the south of England basking in glorious sunshine.

The Met Office said: 'It could be the warmest late August Bank Holiday Monday since it was established in 1965.

'We've not a had a run of several warm days for weeks – so it's good timing for the Bank Holiday weekend.

'High pressure is over the UK, combined with some air arriving from the near continent.'

Red nose day: @catherinejayne0 posted last night: 'Clearly, I don't deal well with the sun #sunshine #burnt #red #sore'. Meanwhile, Valentinadelille admitted that she'd covered her face with sunscreen...but hadn't covered her chest

'Note to self - wear sunscreen': On Instagram, RachaHughes wrote that not only had she not applied protection, she'd also worn a chunky neckless, which had left a white mark in the midst of her sunburn

Frustration: This sun-lover got caught out - and not for the first time it seems. She wrote on Instagram 'Cross-body bag burn, one of the more humorous yet cringe worthy ones I've had'

You'll be fine, they said: Sophie A Morrison bemoaned the advice of friends, after they said she wouldn't get burnt - and she ended up with furious pink shoulders...

Temperatures could soar as high as 30C today as forecasters predict a warm Autumn could also lie ahead.

One in three adults - some 17 million Brits – headed away this weekend, according to VisitEngland.

Nearly a million visitors descended on Cornwall, with 450,000 expected to have visited Brighton, 300,000 in Blackpool, 225,000 in Bournemouth and 200,000 in Great Yarmouth.

A Brighton spokesperson said: 'It’s our busiest weekend of summer.'

Britain now looks poised for the hottest Indian Summer for 11 years, with September highs set to reach up to 31C (88F).

After a cooler mid-week, the Met Office says next weekend will see highs of 23C and a prolonged period of sunshine between September 11th and the 25th, particularly in the country's south.