"The police are receiving several calls about extremely slippery road conditions in several places," the police region Mitt writes on its website.
"Drivers are therefore advised to reduce their speed and keep a safe distance from the vehicle in front."
Roads are also slippery in other parts of the country.
On Tuesday morning, for example, a truck driver said he had lost control of his vehicle on the slippery road on Highway 52 outside Örebro and ended up in the ditch.