SNOW, ICE AND THE FREEZING LEVEL

The Technique

1. Driving in snow country is a skill, and the most dangerous part of it is not the snow. It is the transitions, and specifically the freezing level, where rain becomes ice without changing appearance at all. You are climbing a mountain road in steady rain. The road is wet, grip is normal, everything is fine. Then the ambient temperature crosses zero and the same wet road becomes a sheet of ice, with no visual change whatsoever. This has nearly caught me out more than once, and it is the mechanism behind a huge share of mountain-road incidents.
2. Watch the outside temperature gauge, not the windscreen. Anything from about +4C down deserves your attention. Road surfaces run colder than the air, especially at night, on bridges, and in shade. Watch elevation as well: if you are climbing and the temp is dropping, you are driving toward the transition, not away from it.
3. Watch the spray. When the hiss of tyre spray suddenly goes quiet, the water on the road has stopped being water. That silence is the single best early warning there is. Watch other vehicles' spray ahead of you for the same reason.
4. Bridges, overpasses, shaded corners and the first cold hollow after a ridge freeze first and thaw last. Treat every one of them as ice until proven otherwise. Black ice is not black. It is clear, and it looks like a slightly darker patch of wet road. Late afternoon and early morning are prime time.
5. Everything gets done earlier and gentler. Braking, turning and accelerating all need to happen before you would normally do them, and with a fraction of the input. The rule is one input at a time: brake in a straight line, then turn, then get back on the power.
6. Look where you want to go. Under stress people stare at the thing they are trying to avoid and steer straight into it. Eyes up and down the road.
7. Space is the only real safety margin. Stopping distances on packed snow can be double dry-road distances; on ice they can be many times that. Whatever gap feels right, double it. In a convoy, double it again.
8. Understand what your systems do and do not do. ABS keeps you steering but on ice will often increase stopping distance. Traction control stops wheelspin but does not create grip. Four-wheel drive helps you go; it does very little to help you stop or turn. A lot of the vehicles in ditches are 4WDs, because their drivers had confidence the tyres could not back up.
9. Tyres are the whole conversation. Winter-compound tyres stay pliable below about 7C where all-seasons go hard; that difference is worth more than any drivetrain. Studs or chains for genuine ice. Know how to fit your chains before you need them, in the dark, in the wet, with cold hands. Practise once in the driveway.
10. Descending is harder than climbing. Select a low gear early and let engine braking do the work rather than riding the brakes. If you are losing traction on a descent, gently reducing brake pressure can restore steering.
11. If you start to slide: ease off everything, look and steer where you want to go, and make small corrections. Sudden stabs at brake or throttle are what turn a slide into a spin. And remember that snowbanks, verges and drifts hide things: culverts, rocks, drop-offs, and other people's vehicles. The soft-looking edge of the road may not be road.
12. The pros and cons, honestly. What snow gives you: access to terrain and experiences you cannot get any other way, and forgiving surfaces for learning car control at low speed in a safe, open area. What it takes: margin. Everything takes longer, costs more, and punishes complacency harder. Recovery from a small mistake is genuinely difficult and sometimes impossible without help.
13. Before you go: winter or studded tyres, and chains that fit and that you have fitted before. Full tank, and a plan that assumes you may have to sit still for hours. Warm layers, food, water, torch, shovel, recovery gear, and a way to call for help that does not depend on mobile coverage. Someone who knows your route and your expected arrival time. The current road and avalanche closure information, checked the morning of.

Common Mistakes

Judging the surface by how it looks through the windscreen. Fix: watch the outside temperature gauge and your elevation, and treat anything from about +4C down as a warning.

• Missing the moment the tyre spray goes quiet. Fix: listen for it, on your own tyres and on the vehicles ahead. That silence is the best early warning there is.
• Braking and turning at the same time. Fix: one input at a time - brake in a straight line, then turn, then get back on the power.
• Trusting four-wheel drive to make up for the surface. Fix: 4WD helps you go and does very little to help you stop or turn, and the tyres are the whole conversation.
• Carrying chains you have never fitted. Fix: practise once in the driveway, so the first time is not in the dark, in the wet, with cold hands.
• Riding the brakes on a descent. Fix: low gear early, engine braking doing the work, and gently reduce brake pressure if you are losing steering.

The Drill

Two parts. First, in the driveway, fit your chains end to end without help and without reading the instructions, then take them off again, so the first time is not on a mountain road at night. Second, find a large, open, snow-covered area with nothing to hit and practise at low speed: brake in a straight line, then turn, then get back on the power, one input at a time, until you can feel where the tyres let go and can steer through it looking where you want to go. The standard: chains on in one go, and a slide you can settle with small corrections rather than stabs.

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