Preparing for day-long activity Monday may be a challenge, National Weather Service forecasters warned Saturday night, saying temperatures will drop in the afternoon or evening, and it could snow.

Late Monday morning “will seem balmy” compared to “later in the afternoon/evening,” forecasters in the local weather service office wrote in a discussion of their forecast.

“It is important for the word to get out that there will be a transition on Monday afternoon leading to cold conditions overnight Monday,” the forecasters said.

“People will need to prepare accordingly,” they said. Specialists advised dressing in layers; keeping gloves and a hat handy also seemed advisable.

In a 9:30 p.m. Saturday forecast for the immediate area, the weather service foresaw a cloudy Inauguration Day with highs rising to about 40. They called for scattered afternoon snow showers, with a 50 per cent chance of snow.

Use this map to find your way to and from Metro stations; to locate restrooms, concessions and Jumbotrons; and to navigate your way through security checkpoints to the parade and the Mall.