Senior Sergeant Paul Robertson, of Christchurch, said an officer noticed a vehicle swerving across the centre island, to the kerb on the other side of the road at about 8.30am.
She was stopped by police in Wigram and given an infringement notice for driving with an obscured windscreen, which is a $150 fine.
"With winter officially setting in, this is a clear reminder for motorists to think about safe winter driving," Snr Sgt Robertson said.
"If you are ever in this situation, there are ways to safely and quickly defrost your windscreen, and we urge drivers to do so before they head out."
Snr Sgt Robertson said it was also important to allow extra time before your drive, in order to check over your vehicle and safely drive to the road and weather conditions.
