Seeing as global warming and climate instability are now bringing us conditions at a time of year when we might reasonably expect to be able to walk to the car without getting frostbite, it pays for the modern motorist to be prepared for all sorts of different weather conditions.

Summer 2013 will probably be a damp fizzle with one day (not a Bank Holiday) at just over 27 degrees and the rest flatlining in lukewarm dullness. But what if those crazy meteorological dice land sunny side up and you find yourself sitting in a motorway tailback or inner-city logjam with no air conditioning option?

We’ve collated a survival guide to ensure you and your companions don’t go loco and yet still stay cucumber-cool.

1. Feeling hot, hot, hot? If you failed to specify air conditioning on your latest wheels and there’s a big blanking plate where the button should be, or you simply haven’t had the system overhauled, you may find yourself gasping like a Pekingese on a parcel shelf.

First tip is not to panic, it only makes things worse. Simply get a bottle of water and douse it over a rag (or donated piece of clothing) before placing said soggy garment over the air vent. The moistened material will cool the inflowing air noticeably and help reduce the risk of tantrums.

Do not, if water is unavailable, improvise with other solutions. It will probably makes things worse.

2. If you saved some water from that bottle, pour it over your head (having got out of the car beforehand).

This is an effective way to recalibrate your inner thermoregulatory system. If you score more than 37.5 degrees on a thermometer, you’re dangerously uncool.

Driving barefoot is also a good measure, given that socks that make you feel cool are yet to be invented. Keep some driving sandals on board for such purposes and to hell if they clash with your slacks.

3. Beyond a strict avoidance of Radio 1, shade and fans are your final weapons in the struggle to avoid in-car immolation.

Most fans are cheap (check with your local pound store) and plug into the cigarette lighter. Used in conjunction with windows that are opened at least a little both front and rear, they help to create a precious flow of air when you’re sitting in static.

Shade isn’t always so available, and if you’re crawling in a motorway tailback, there is only a certain amount of extra time that you can linger under a bridge before those behind you decide to take matters into their own hands.

And remember that “feeling hot” is unlikely to be construed by police as a good reason for anchoring on the hard shoulder, let alone setting up a hammock in the overhanging greenery.

4. Early DIY air con systems in the USA consisted of a block of ice slung into the footwell.

Bags of ice are inexpensive but not recommended for the attendant risks of consequent in-car flooding.

In India, some motorists rig up home-made air conditioning units which consist of a roof-mounted radiator fan – when the fan spins as the car moves along, the power from it operates the air con, with no added fuel consumption (though such a device does, of course, increase drag).

5. Blacking out your windows might associate you with the kind of motorists who don’t want you to see them hitting their kids while they’re driving to Asda, but this customisation does make it cooler, temperature wise, and is also said to help preserve your upholstery by cutting down the incoming UV rate.

Black clothes, incidentally, will not make your journey cooler; Bedouins apparently only wear black to scare tourists. Black bodywork, however, is definitely a bad choice if you like dawdling on the Dorset riviera.

A test by the Australian TV show Mythbusters proved that in strong sun a black car ended up five degrees celsius hotter than a white one.

And if your AC-free car is white, there’s another bonus too: it’s estimated that if all the world’s motors had white roofs, global warming could be measurably reduced.

• This summer’s cooling read has to be Polar Nights, penned by Diesel Car’s very own Simon Hacker. Set in a savage storm in Scotland, it’s a dark eco-thriller, the chief villain being a marauding polar bear with a penchant for human flesh. Expert reviewers at e-thriller.com say Simon’s debut novel is “lovingly crafted” and “different, humorous and engaging”. Find out more at amazon.co.uk