It might still be wet and windy here, but in New York, the city that never sleeps in the summer because it’s just too damn hot, the mercury has risen – temperatures are in the high 20s and rising.

Your only options for a summer city break? Sweat buckets or cocoon yourself in the relentless air conditioning. Unless, of course, you head for one of the Big Apple’s hottest/coolest rooftop bars. Here are this season’s best...

THE ROOF CLUB AND GARDEN AT THE GRAMERCY PARK HOTEL

This summer, the roof bar in Manhattan isn’t just the prettiest, it’s also the most difficult to get into. The members-only rule is easily circumvented, however, as hotel guests also have access. Not a cheap way to jump the velvet rope, but admirably simple.

The 16th-floor club, reached by a private keycard-operated lift, has a garden terrace filled with orange trees, ivy and geraniums. The retractable roof is wrapped around a series of drawing rooms designed by the artist Julian Schnabel. Replete with modern art (Hirst and Warhol) and Alist regulars, it amply fulfils owner Ian Schrager’s vision of an exclusive country club in the city. The cocktails are pretty good, too.

If the Gramercy is full, then A60, at 60 Thompson in SoHo, operates a similar members- and guests-only policy. It has an equally delightful open-air terrace – and a great line in lychee martinis.

Gramercy Park Hotel: 00 1-212 920 3300, www.gramercyparkhotel.com; doubles from £340. 60 Thompson: 877 431 0400, www.60thompson.com; doubles from £350

THE ROOF GARDEN AT THE MET

There’s a splendidly democratic feel in the air at this glorious roof terrace, slap bang in the middle of the Upper East Side, one of the most expensive real-estate areas of Manhattan. The view has multimillion-dollar stamped all over it, yet it’s yours all day long for the price of admission to the Metropolitan Museum of Art.

The views over Central Park and Midtown are so gobsmacking and so romantic, it’s hard to understand why the terrace isn’t packed with couples professing endless love. It may be something to do with the fact that the entrance is a discreet lift just past the European sculpture court on the ground floor of the museum. After you’ve admired the extraordinary Frank Stella sculptures, buy a sandwich, treat yourself to a glass of sangria – a potent and peculiarly New York obsession – and don’t miss the Rodin lurking by the entrance.

00 1 212 535 7710, www.metmuseum.org; roof garden open until October 28, weather permitting

ROOFTOP AT THE DELANCEY

First, a warning. The Lower East Side may be on the up, but this bar, nestling at the foot of the distinctly unglamorous Williamsburg Bridge, does not fall into the “hidden chic” category; instead, it’s in the “hidden slightly grubby hipster” one. It’s certainly not the bar I’d visit with my mother. Still, this agreeably relaxed large terrace atop a two-storey rock venue is crammed with a good-looking and friendly under-35 crowd.

There’s no cover charge, and the attractions include a frozen-margarita machine, as well as lots of palm foliage and a water feature complete with stone frogs. It’s worth ringing ahead to check that the roof isn’t hosting a private party, however, as the ground-floor bar is dark and gloomy.

00 1 212 254 9920, www.thedelancey.com

SOHO HOUSE AND HOTEL GANSEVOORT

You’ll find not one but two rooftop swimming pools atop boutique hotels in the slowly gentrifying Meatpacking District. The only drawback: a dip is going to cost you. Soho House is for members and hotel guests only; Hotel Gansevoort charges nonresidents a flat rate for pool use across the summer. Which is better? Soho House wins hands down. Trendies may raise a sardonic eyebrow and set their sights on newer venues, but the consistently charming and rapid service, the huge wooden roof deck and the outdoor restaurant still attract a sexy, grown-up crowd. By day, they lounge around playing backgammon, drinking smoothies and admiring their tans. In the evening, the pace cranks up and the beautiful people hang out under the stars. (It’s worth bearing in mind that noisy children inhabit the pool until 12.30pm at weekends.)

By comparison, the Gansevoort’s rooftop lounge, called Plunge, just doesn’t cut the mustard. The pool is a good size, great for proper swimming, but you have to pay £128 for a three-month membership if you want a dip. The rest of the mammoth space is given over to the separate bar area, which most nights becomes ludicrously packed with an overexcited, out-of-town crowd drinking fluoro cocktails.

Soho House: 00 1 212-627 9800, www.sohohouse.com; doubles from £291.

Hotel Gansevoort: 206 6700, www.hotelgansevoort.com; doubles from £215

RISE BAR AT THE RITZ-CARLTON, BATTERY PARK

It’s all about the maritime view at this 14th-floor bar in New York’s only luxury waterside hotel. Order a Skyy Rise, the moreish house cocktail, ignore the bad late-20th-century corporate-bar interior and concentrate instead on the extraordinary panorama afforded by being on the southernmost tip of Manhattan. In front of you is the whole of New York harbour, with the Statue of Liberty and Ellis Island in the foreground and the New Jersey skyline behind. The outside terrace is open from May to September.

00 1 917 790 2626, www.ritzcarlton.com; doubles from £317

BOOKMARKS AT THE LIBRARY HOTEL

Although the Midtown after-work crowd swarms to the Pen-Top bar at The Peninsula hotel, the smart choice in this part of town is the smaller, more elegant Bookmarks, just a few blocks away. Filled with flowers and wrought-iron furniture, the outdoor terrace has the feel of a private uptown penthouse. It’s perfect for a presupper drink, and a good place to take visiting relatives who might be scared by trendier options. A sense of humour is evident in the cocktail list: you can choose which literary hero to drink to, perhaps by knocking back a rum-based Hemingway or tipping an ironic wink to the bibliophile surroundings with a citrusy Jackie Collins. Bookmarks is open to nonresidents, but reserve a table if you want to be sure of a seat.

The Peninsula: 00 1 212-956 2888, newyork.peninsula.com; doubles from £305.

Library Hotel: 983 4500, www.libraryhotel.com; doubles from £272

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