When weather conditions call for snow or ice our maintenance foreman monitors the roads to see when or if the plows need to be sent out. When visibility due to falling and blowing snow is continually making it impossible to see, MN / DOT is generally the first to announce through the media that it is pulling the plows off the road. They also started this past winter with announcing which of its roads are then designated as "closed".
Counties generally are out somewhat longer, but also have to quit due to the operation simply not being safe, if the operators cannot see the road. No snowplowing after sunset has always been Nicollet County's practice for all of its roadways. An individual emergency is treated as such with the Sheriff making the decision to request a snowplow unit to lead an emergency vehicle. There is just 1 snow and ice crew of operators for the Nicollet County routes and federal law limits the hours they can operate equipment within 1 24-hour day.