Notebooks seized from thieves have revealed the methodology in which offenders are "staking out" neighbourhoods, watching and planning for a future opportunity to swoop in and drive the warming cars away when the victims step back inside their homes.

The seized notebooks reveal the times - often as early as 5.30am - and locations. And the notes even reveal the recording of other valuable personal property at target homes, such as mountain bikes, which could be stolen later.

It's a fresh twist on a common Canberra winter problem and one that has surprised seasoned officers like acting Detective Inspector Jason Dziubinski.

"We [police] haven't seen this level of planning by thieves before," he said.

"The problem of people leaving theirs cars running in their driveways to warm up and defrost early in the morning and then having them stolen in basically, just seconds, has been a problem for a long time in Canberra.

"Even last year, during a COVID-affected winter in which a lot of people were working from home, we still had 21 cars stolen like this.

"But this [intelligence-gathering by thieves] is something relatively new."

Standard immobilisers and modern vehicle anti-theft measures, with rolling codes built into the engine management software, now make it almost impossible for all but professional thieves to "hotwire" a car.

So for the opportunistic car thief, stealing a car now requires getting hold of the all-important key code built into the key fob or the key itself.

That means either breaking into a property and stealing the key fob, or alternatively getting up in the early hours and scoping the suburbs, keeping a written record of the Canberra streets and houses where people are doing the driveway warm-up, then planning to return another day and strike.

ACT Chief Police Officer Neil Gaughan said Canberra's car theft issue has surged over the past six to 12 months, going against the trend seen in other states and territories.

"We're probably the only jurisdiction which has had an increase in the past six to 12 months or so; most jurisdictions are seeing a decrease," he said.

"We've seen a 5 per cent increase [in car theft] since July 1 last year. Most [vehicles] have been stolen just by using the keys.

"People are leaving their houses insecure or [thieves] are breaking into houses; we did have a run last year of cars being stolen as a result of young people going into gyms and having their car keys stolen from the insecure locker area.

"People still like to live by the fairy-tale almost that Canberra is still a big country town and these sort of things won't happen to me but the reality is that in the 12 months to April 30, almost 1400 cars have been reported stolen to us.

"So that's not a small number."

Another car issue, but more road safety-related, and yet also allied to Canberra's frosty winter mornings, is of people driving around with their car windows obscured and unable to see clearly around them.

As overnight temperatures in Canberra have plummeted into the minus category in the recent week, police patrolling the roads are seeing many cars driving with their windows and exterior mirrors coated in frost, creating a safety hazard.

Senior Constable Aaron Cherry, who rides a police bike, has attended several collisions attributed to this lack of visibility from the driver's seat in recent days.

"It is a safety issue and we should remind motorists that not having full visibility around you not only puts yourself at risk but other vulnerable road users, like cyclists and pedestrians," he said.

"We remind motorists that it is an offence to drive without clear view, and that carries a monetary penalty of $205."

Free ice scrapers are being provided to Canberra motorists. These are available from the front offices of all police stations in the ACT.