Can we talk about the weather? Is there even any other subject right now? It is the beginning and end of every conversation. How marvellous it is, how lucky we are, obvs, segueing rapidly into the kicker: what on earth to wear? Holiday weather is a breeze when you are pulling a dress on over a bikini. But when you are still on-duty and expected to look smart, summer dressing is a challenge.

But as luck would have it, there is a masterclass on how to look smart in the summer being broadcast live from London for most of the day, almost every day, for the next fortnight. It’s called Wimbledon. While the rest of the country flails hopelessly around trying to figure out what to wear when your work wardrobe doesn’t suit the climate but your holiday wardrobe doesn’t suit the vibe, one corner of SW19 is showing us how it’s done.

Wimbledon is Britain’s best-dressed moment of the year. London fashion week has too many outsize trainers and miniature sunglasses; the Baftas has that baffling “it’s early February, I think I’ll stand outside in a strapless dress and no coat” goosebumpy thing going on; Ascot is Halloween for posh people. Wimbledon, on the other hand, is bona fide summer chic. And Wimbledon is more fashionable than it has ever been, because it lies at the crossing point of two axes of power in style this decade. SW19 is where the glamour of sport and the allure of the royal family come together – and the stock of both in fashion is at an all time high. The unstoppable rise of athleisure has made playing sport (or performatively watching sport, as exemplified by the royal box) more high-profile than ever. And the passing of the Wimbledon baton to a younger generation of the royal family (the Queen, not a tennis fan, has only ever attended four times) has amplified its profile by having coincided with the impact of the tennis-obsessed Middleton family in the royal landscape. Pippa Middleton is even more of a keen fan than her sister, and counts Roger Federer a close enough pal for him to have been a guest at her wedding last year.

Serena Williams on the cover of Harper’s Bazaar, July 2018 Photograph: Richard Phibbs/Harper's Bazaar

If you don’t believe that strawberries and cream at Wimbledon now constitutes fashion’s top table, consider this. Serena Williams, the Duchess of Sussex, the Duchess of Cambridge, Victoria Beckham and Anna Wintour are probably the five most influential women in fashion in 2018, and the All England Club will probably play host to all five before next Sunday. Serena Williams, recent American Vogue cover star and currently to be seen in a Dior bodysuit on the cover of Harper’s Bazaar, is dominating early storylines on Centre Court as she returns from maternity leave. The new Duchess of Sussex, whose every public appearance leads to an instant sellout of whatever she wears, is a tennis fan (she attended in 2016) and pretty much a dead cert to support her friend Williams. The Duchess of Cambridge is a tennis nut and patron of Wimbledon. Victoria Beckham is a regular at the men’s final. As eight-times champ Roger Federer’s most loyal fan, Anna Wintour is sure to make an appearance as he defends his title. This is a power front row like no other. Oh, and Beyoncé – another friend of Williams, who has attended Centre Court as her guest – is in Europe, so don’t rule out a courtside cameo from the Carters, if they can carve out a moment from their tour schedule.

Beyonce and Jay Z at the Wimbledon women’s final between Serena Williams and Angelique Kerber in 2016. Photograph: Karwai Tang/WireImage

Wimbledon uniform by Ralph Lauren.

But the A-list are not the point, because what makes Wimbledon truly relevant to the business of getting dressed is that its fashion power does not derive from untouchable haute couture wardrobes. The joy of Wimbledon is that everyone is chic. The famous all-white dress code ensures that every on-court shot is a pure visual harmony. Then there is the Gatsby-esque dreaminess of the Ralph Lauren uniforms. Ballgirls and ballboys wear simple preppy navy polo shirts and polo dresses, while umpires and line judges wear blazers and smart cream slacks. The elegance of the uniforms is a lovely thing, because it makes those working at Wimbledon as central to the glamour of the place as the Duchesses in their Alexander McQueen tea dresses.

Dress, Zara, £29.99 Photograph: Zara

The many style lessons to be learned from watching Wimbledon begin, of course, with white. When you want to look cool and calm in summer, all-white is an excellent place to start. Who wouldn’t take style tips from Roger Federer, the snow-white Centre Court dream whose appearance at this year’s opening press conference caused a reporter to blurt out that he was looking “even more handsome than last year”? I have never mastered wearing white on holiday (incompatible with a regime of spaghetti vongole and pistachio ice-cream) but I have learned that when you want to look competent and chic, white is the simplest formula for summer power dressing.

Blazer, £49.99, zara.com Photograph: PR Company Handout

Also, blazers. If you are still harbouring inverse snobbery against the blazer, take a good look at Wimbledon and then at yourself. It is true that if you wear a blazer with a striped shirt and a panama hat and ostentatiously expensive watch, you will look ghastly. But if, on the other hand, you wear a blazer with your normal wardrobe you will find it neatens the edges of your look in a pleasingly no-effort kind of way. The key is not to shy away from going full-on blazer and thereby end up in a boring suit jacket. Gold buttons? Great, wear the blazer with a white T-shirt and cropped trousers and gold hoop earrings. Double-breasted? Surprisingly flattering thrown over a sundress.

The Wimbledon “look” is smart, but not fraught. Even in the royal box, the dress code for female spectators is surprisingly relaxed. This makes Wimbledon an infinitely more useful template for what-to-wear-in-real-life than the royal enclosure, Ascot, with its compulsory millinery, or the Met Gala with its impossible dress codes (this year, if you recall, was Catholic chic). Self-Portrait is a popular label – Pippa Middleton wore one of their dresses last year, and Beyoncé the year before that – reinforcing its status as the home of formal-but-still-fun dresses. Sienna Miller in a cream Galvan jumpsuit, red lipstick and tortoiseshell sunglasses (2015) will forever serve as a reminder that the Talented Mr Ripley school of summer dressing takes a lot of beating.

This year’s Wimbledon is only just hotting up, but the fashion game is strong as ever. For day one, Mirka Federer teamed her deckchair-striped cotton shirt with a Gucci belt while Laura Carmichael wore a Ganni wrap dress: two strong summer looks, right there. The grass is green, the dress code is white – but this is a red carpet. Pour yourself a Pimm’s, and watch.