See the Washington, D.C. area operating status to find out if the government is open, closed, or "open with option for unscheduled leave or unscheduled telework."
Operating and leave policies for federal workers have changed several times in the last few years. In 2018, OPM issued new regulations related to the use of weather and safety leave.
In general, telework program participants will not receive weather and safety leave, since they are not usually prevented from performing work at their telework site (usually home) due to a weather or other safety-related emergency.
You are responsible for making all appropriate preparations in anticipation of a weather or other emergency event. The regulations specifically say that if you need your laptop to perform your work from home, and a significant snowstorm is predicted, the agency may not provide weather and safety leave if you cannot do your work because you failed to make necessary preparations for reasonably anticipated conditions. In such a case, you would need to use other appropriate paid leave, paid time off (such as comp time/credit hours) or leave without pay.
When OPM announces an early dismissal, departure times will be based on individual schedules. Employees also have the option of requesting unscheduled leave or unscheduled telework for the time prior to their personal early departure times. Last December, OPM announced that unscheduled telework is an option for Federal employees with existing telework agreements when severe weather conditions or other circumstances disrupt commuting.