Sun-starved Brits could be putting themselves at risk of skin cancer by rushing to soak up the rays on the hottest April day for 69 years, warned experts.
They fear that, after a long period of cold weather, many sun-worshippers may not 'slip, slop, slap' to protect themselves properly from harmful UV rays.
The hottest spot was RAF Northolt in Middlesex where the mercury soared to 28.8C (83.8F), just short of the all time record for the UK April maximum temperature of 29.4C (84.9F), and the warmest April day since 1949.
The cool spring breeze also gives sun-bathers a false sense of security - adding to the cases of burnt skin.
Plunging temperatures caused by the Beast from the East last month left thousands any without water supply, grounded hundreds of flights and caused travel chaos across the country.
Since temperatures dropped to below minus 10C, the mercury has continued inching its way up the barometer this month.
But, after such a long winter, there is a good chance many people are going to wake up a bright shade of red, according to the British Association of Dermatologists (BAD).
Feelgood factor 30
Dr Sweta Rai, of BAD, said: "Obviously the sun has a feel good factor and as soon as the first signs of summer come people want to get out into the sun.
"When the sun comes after a long period of cold, some people haven't had a chance to pick up sunscreen.
"There's also an issue with people going out at their lunch break for an hour without any form of sunscreen. It's easy to get caught out.
"People are not used to the sun as it's been cold for a long time - the skin has not seen any sun so it's not weathered.
"We know people are aware of the risks but we hope if they have a bad experience it will change their behaviour in the future.
"At this particular time of year it can be dangerous because people associate sun protection with June and July so don't use it earlier in the year.
"You can't take it at face value as to whether it seems sunny or not, you can still get sunburn through cloud clover. You have to look at the UV index for that day."
Dr Rai, who works at Kings College Hospital, London, said dermatologists often see a rise in sunburn cases at this time of year because many people don't realise they are getting damaged by harmful rays.
She said: "We recommend keeping your body armour with you by always carrying a bottle with you and wearing factor 30 or above.
"You have to apply it two hours before you go out and reapply every two hours. If you are going in water reapply every 40 minutes as it will wash off - even if it says it is water proof, as this is misleading and will still wash off.
"I'm all for people having a good time, the idea is to be safe in the sun, not to stay out of it. We want people to enjoy the sunshine and ensure it is done responsibly.
"If you do get badly burnt you are at a higher risk of developing skin cancer in the future."
BAD experts also recommend wearing sunscreen under clothes to "double up" protection against harmful UV rays.
Wear protective clothing, spend time in the shade during the hottest part of the day between 11am and 3pm, and use a sunscreen with a minimum SPF of 30 and good UVA protection, BAD say.
Anyone suffering a burn should soak skin in a cool bath or even with a flannel will temporarily reduce discomfort, then use aftersun, calamine lotion, or a light moisturiser to help reduce peeling, experts say.
At the point of feeling dizzy or sick, having blistering or badly swollen skin, see a doctor as for possible treatment for dehydration or to prevent infection, warn doctors.