'Tis the season to be jolly--and with under two weeks to go before Christmas, drivers across the country will be planning trips to see relatives and friends for the holiday period.

Driving in the middle of winter already presents its own unique challenges, but if you're looking to get good gas mileage it's worth heeding a couple more tips.

Of course, you'll probably spend those saved gas dollars on food and gifts anyway, but that seems like a fair swap to us!

Tip #1: Plan ahead

You might have taken your winter route several times before, but it's worth having a look at alternatives, just in case your route is blocked by traffic or bad weather. Getting stuck in a huge line of traffic over Christmas isn't just frustrating--it can waste a lot of gas too. For that reason it's always best to have a Plan B.

Drivers with in-car navigation or smartphones should also be able to check up on conditions and traffic while on the move, giving you a further advantage. That's particularly useful on longer journeys, where conditions may have changed since you set off.

Tip #2: Prepare your car

Whether you live in a Snow Belt state or somewhere with a more clement climate, your tires are important. Winter, summer or all-season tires all need to be pumped up to the right pressure, and a quick check of their condition and tread depth. The legal minimum tread is 2/32 of an inch (to the top of Abe Lincoln's upturned head on a penny!), but particularly in adverse weather you'll want a lot more than that--ideally over double the legal minimum. Check out our full tire guide here.

If you can fit all your winter paraphernalia in the trunk rather than a roof box, that'll save you gas too with better aerodynamics; and it's always wise checking windshield washer fluid before you set off--it won't save you gas mileage, but it'll ensure you have good vision in adverse conditions.

Tip #3: Set off early

As with tip #1, mitigating for traffic and poor driving conditions can be useful for saving gas. By setting off early, you might not only beat some of the jams over particularly busy periods, but you may be less inclined to drive quicker, making up for lost time.

Tip #4: Take it slow

If you've listened to tip #3, then tip #4 is much easier to follow. If you're not in a rush, then there's little need to speed. Chances are, busy traffic conditions may prevent you going too quickly anyway, but on long and open stretches, just set the cruise control and relax.

There is an exception to that, of course--much as it can be good for gas mileage, never use the cruise control on icy roads--varying levels of grip can confuse the system and result in dangerous bursts of speed as tires lose and re-gain grip. Economy is good, but safety should always be paramount.

Tip #5: Use accessories in moderation

We know it's sometimes unavoidable using accessories, particularly in northern states with shorter days and colder weather. Lights, heaters, radios and more may spend long periods in use.

You may be surprised how little you need, though. Firstly, if your car has heated seats or even a heated wheel, those are more effective at warming the parts that count than turning the climate control to full power.

And as for the climate control itself, does it need to be turned up to 80 to keep you warm, or would a nice 65-or so do? If you live in a colder climate you probably have warm clothes with you anyway, so wear an extra layer to keep warm!

Tip #6: Remember your eco-driving skills

It can be hard to concentrate on your driving with the kids singing along to Christmas songs (or arguing...) in the back seat, but even with a full car you can practice your eco techniques.

In fact, smooth driving, slowing early, accelerating gently and keeping a constant speed are all tips which work equally well in poor conditions as they do for saving gas, so it's worth keeping them in mind.

Anything else?

Will you be embarking upon a journey this holiday season? Have you any tips for your fellow Green Car Reports readers? Leave them in the comments section below!

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