Winter driving

During the winter months as conditions change, you’ll need to adjust your driving to keep yourself and other people travelling safe.

Conditions during winter vary throughout the country and can often change fast. Be prepared for all conditions from rain and fog through to frost, ice and snow.

Driving for winter conditions

• Adjust your speed to suit the conditions—when icy or snowy, drive slower than you normally would to reduce the risk of losing control or skidding
• Be seen—use your headlights in rainy, icy, snowy and dark conditions
• If your vehicle turns headlights on automatically when it's dark, you might need to manually turn your headlights on—the automatic function often doesn't activate during daytime, even when visibility is low
• Increase your following distance during poor weather such as rain, hail, snow and fog—it takes longer to stop on slippery roads
• Always check the weather and road conditions before you head out
• Be prepared for delays—we monitor the conditions of state highways and to keep people safe will proactively close roads when conditions worsen
• Whenever you travel, check the conditions before you head off, especially as it gets darker and when conditions get worse
• It’s illegal to drive through a closed road—don’t put yourself and other people at risk by driving through a closed road
• Avoid sudden braking or turning movements to reduce the risk of skidding
• When you’re travelling long distances, make sure you’re well rested, take breaks often, and where possible share the driving
• Check for traffic and travel updates on our regional Facebook pages or Journey Planner nzta.govt.nz/journey-planner.

Driving in snow and ice

Visibility is especially important in snowy conditions. When it’s snowing, you should have your headlights dipped—not on full beam (high beam)—and you can use your fog lights if your vehicle has them.

When heading out in icy or snowy conditions, dress for the conditions, carry warm clothes, water and snacks in case you get stuck or need to wait for conditions to pass. You should also make sure you have at least half a tank of petrol in case of detours and diversions.

If you’re planning to drive in snow and ice, aim to travel in the middle of the day when visibility is better,

If you get stuck in bad conditions, pull over somewhere safe and call a towing company to help you out. If it is an emergency, call 111.

Maintaining roads in winter

Our winter maintenance crews constantly update highway conditions as conditions change and closures occur. Maintenance vehicles will be on roads throughout the country helping to keep them open, safe and accessible. If you come across any of these vehicles, stay a safe distance behind them and do not pass unless you’re instructed to.

Be cautious and take care once you’ve passed the maintenance vehicle as the treatment won’t have been applied ahead of them.

During winter, grit and anti-icing agents such as Calcium Magnesium Acetate (CMA) or Sodium Acetate (NAAC) are spread or sprayed on some roads to help travel in icy conditions. Grit, CMA, and NaAc lessen the severity of winter road conditions but do not completely stop the effect of ice and snow—always drive to the conditions and slow down.

The speed at which ice and snow can occur means that there will be times when grit and CMA/NaAc have not yet been spread. If we have spread grit, drive on it where possible and not in a wheel track, to maximise its effect.

Winter tyres

Winter tyres, also known as snow tyres, are made with a softer rubber compound and deeper treads specifically designed to maintain grip in wintry conditions, ie cold weather (below 7°C), ice and snow.

If you’re travelling in snowy conditions often, consider having winter tyres fitted. Only use winter tyres when and where they’re required, and never mix winter tyres with other tyres.

Winter tyres can be dangerous if they are not fitted or maintained correctly. You need to make sure that the following two requirements are met:

• If you need winter tyres on your vehicle, they must be fitted on all road wheels.
• Winter tyres must have a tread depth of at least 4mm in the grooves of the tyre that usually contains tread depth indicators.

If a vehicle fitted with winter tyres is presented for a warrant of fitness or certificate of fitness inspection and does not meet these two requirements, the vehicle will fail its inspection.