It's the middle of winter but you see them everywhere – teenage girls setting off for a night out in strappy dresses, crop tops and bare legs. Teenage boys wearing T-shirts, jeans and - in a few mad cases - shorts. Brrrrr. Just looking at them makes me shiver uncontrollably. Not a coat or jacket in sight.
Why do teenagers hate wearing coats so much? When I canvassed a few of my friends' children they came up with a multitude of theories.
Some reckon coats are boring ('almost as bad as slippers,' said one in disgust), look horrible and spoil the line of their outfits.
Others protest that coats are too bulky and they get fed up with carrying them around all day, especially when there aren't any lockers at school.
Another told me: "The reason teenagers don't wear coats on nights out is that they don't want to pay to put them in the cloakroom and anyway, it's really hot once you're inside a club."
A 40-something friend said that coats still remind her of school. "I avoid wearing one to this day if I possibly can – a jacket if I must, but never anything longer than my upper thigh."
She's not alone in her coat aversion. My own teenage son loathes coats with a passion and swears he doesn't feel the cold.
When we set off for the cinema in sub-zero temperatures the other night I was wrapped up in a thick coat, woollen scarf and my favourite fingerless gloves. Even my husband, who's a million times hardier than me, was wearing a jumper and sheepskin-lined leather jacket. Striding happily along beside us was our son, dressed for a balmy summer's evening – in jeans, lightweight canvas trainers (with holes in the soles), no socks and a cotton shirt from H&M.
He's six foot four now and very stubborn, so I knew I couldn't force him to wear a coat. But it was so cold that I couldn't feel my fingers, let alone my toes. I had to say something.
"Er, don't you think you should wear a coat?" I asked tentatively, knowing full well the response I'd get.
He rolled his eyes at the very idea.
"Why? It's not cold at all," he retorted, adding that he was old enough to make up his own mind and I shouldn't interfere.
My daughter, now a student in London, was exactly the same at his age. Even on the coldest, wettest days she'd head for the school bus wearing a jumper and short school skirt and insist she didn't feel chilly in the least. "I'm fine," she'd mutter, "really warm" – oblivious to the fact that her teeth were chattering and her lips were blue.
When I asked her what sparked her hatred of coats she blamed "those horrible fleeces we had to wear at school. There were all sorts of rules about what sort of coat we could wear, so it was better not to wear one at all."
Over the years I've done everything I can think of to persuade my children to wear coats. I've droned on about the weather, I've warned them they might get hypothermia and I've even tried bribery. All to no avail.
I've also spent a fortune on chic winter gear, figuring that if I bought my son a stylish Superdry jacket that he really liked, it would do the trick. The jacket, a double-breasted number with a ribbed collar and cuffs, cost a small fortune but he chose it himself and it seemed to work – for a few days at least.
Then one evening he went out for a pizza with friends in Oxford. When he arrived at the restaurant he carefully hung his coat on a hook by the door and joined his pals a few tables away. But when he went to retrieve it an hour later it had vanished into thin air. In its place was a flimsy cotton anorak – obviously left by the person who'd nicked my son's lovely, warm coat.
The following day the temperature dropped to minus two degrees so, worried that he was going to freeze, I went out and spent my week's earnings on an identical one. An identical one that was soon consigned to the back of the cupboard.
I just hope that he'll eventually follow his big sister's example and wake up to the wonderfulness of coats. One day, without any warning, my daughter announced that she was off to Topshop to buy a winter coat. She came back a few hours later with a stylish navy duffel coat that she's worn non-stop ever since.
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