Montgomery County is getting ready for winter's worst.

Departments and agencies throughout the county on Thursday will simulate their response to a 20-inch snow storm causing power outages to 300,000 households.

The county will use its emergency operations center for the exercise, and snow plows will run routes along the 5,000 miles of county-maintained roads.

D.C. rolled out its snow plows in a similar exercise Oct. 28, the day before a surprise autumn snowstorm hit the area.