HALF an hour.

That is all the time it takes to go from sunshine to snow in New Zealand's mountainous regions.

And the popular tourist ski resort of Lake Wanaka in Otago is no exception.

When a snowstorm hit the area last Thursday, a car believed to be driven by Singaporean student Nur Haryani Mohd Hatta, 24, slid off the icy roads and plunged 120m into the lake.

One of the three other females in the car, Malaysian Veronica Tan Lee May, 20,
was killed in the accident.

All four are international students at University of Otago.

Ms Nur Haryani's parents have flown to New Zealand to be with her.

She was discharged from Dunedin Hospital yesterday.

A university spokesman told The New Paper this morning that the other two survivors are still in hospital.

One of them is expected to be released today, while the other in the next
couple of days.

But volatile weather is not all the four students had to contend with.

There is an extremely dangerous hazard called black ice.

Were the women even aware of the risks involved?

Mr David Turner, 30, a policy analyst who has lived in Singapore for the past two years, grew up in Otago.

He said the water that freezes on roads can form a deadly, slippery layer called 'black ice'.

He said: "You can't see 'black ice' because it is transparent, and it is more dangerous than a road frozen white by frost because it is even more slippery.

"I've driven on ice before and it's scary. When you hit 'black ice', you can lose complete control of your car."

If that happens, Mr Turner said drivers should not hit the brakes, but steer in the direction that the car is going in until it regains traction.

He noted: "Tourists won't have been taught what to do if they hit 'black ice'.

"And it can be too late if the driver was going too fast in the first place."

He also said the best speed on such treacherous weather conditions is 'jogger's
speed'.

"The roads are slippery and visibility is poor when it snows," Mr Turner said,

"So you have to go slowly - at a jogger's pace.

"In the Lake Wanaka area, you drive on windy, rural countryside roads.

"Even experienced drivers familiar with the road conditions, and who have the right car, need to be careful."

The 'right car', he explained, would be a four-wheel drive with snow chains that give the car a better grip.

Rental cars are usually not equipped with snow chains.

Ms Nur Haryani was reportedly driving a rented 1996 Mazda Familia.

Mr Turner said people do not usually carry snow chains in their cars unless they expect a snowstorm.

'PLAN FOR SNOW'

And he said advance weather warnings are usually issued before a snowstorm hits
so people can 'plan for snow'.

Newspaper and TV reports carry warnings up to two days in advance.

Weather updates are broadcast every half hour on the radio.

Ski resorts also put out reports on weather conditions and whether any roads will be closed.

But Mr Turner warned: "In the mountains, it can snow at a moment's notice. At Lake Wanaka, it can change from sunny to snowy in half an hour."

He said it is not unusual for tourists to be involved in car crashes in New Zealand.

Research by the University of Otago, commissioned by the Land Transport New Zealand, showed that 8 per cent of the crashes in Otago in 2003 involved overseas drivers.

Mr Turner said there have been many road-safety campaigns in New Zealand in the last few years.

And the New Zealand Police website showed that road deaths have been dropping for the past decade.

However, the messages in the road safety campaigns do not reach tourists and international drivers.

Mr Turner said: "Many Singaporeans are not used to the open roads in New Zealand and might misjudge the speed when taking corners."

He advised tourists who are driving in New Zealand in winter to check weather reports before heading out.

They should also take with them extra sets of warm clothing in case they get stranded in heavy snow.

He said: "If the weather conditions change for the worse, you should pull over to the side and wait it out.

"It is quite foolish to be driving in bad weather conditions when you're not used to them.

"Or if you have to, drive very slowly in low gear."

That is one lesson Singaporean Han Songguang, 26, who continued driving during a snowstorm, won't forget.

The NUS master's student was on a road trip to the Grand Canyon in the US in early April.

He and his three friends were about to leave the Grand Canyon for Las Vegas when it started to snow.

Mr Han recalled: "We were all very excited because it was the first snow we saw in the US in a week.

"But as we drove, the snowfall became heavier. The ground was quickly covered in inches of snow."

The group worried about not having snow tyres. They had not expected to need them as it was spring.

But it happened that the US was going through a freak weather period. Even though it was the afternoon, the sky was dark and overcast.

POOR VISIBILITY

Mr Han said: "My biggest worry was visibility. The windshield wipers were not
having any effect at all.

"It got to a point where we couldn't see beyond 3m in front of the car."

He recalled how parts of the highway were not lit.

And how some roads had only two lanes, one for each direction.

He said: "There was not a lot of room for error on those roads.

"If a car coming from the opposite direction didn't have its headlights on, I wouldn't have seen it until it was too late.

"But I was more worried about driving off the road into a ditch or drain than
hitting another car."

At the very next sign for a motel, Mr Han exited. But it was full of travellers taking shelter from the snow.

So he drove at a snail's pace to the next motel where they stayed the night.

He said he was driving at speeds of between 20kmh and 80kmh.

Tourists won't have been taught what to do if they hit 'black ice'. And it can be too late if the driver was going too fast in the first place.
- Policy analyst David Turner, who grew up in Otago