Snow first started falling in Washington's western suburbs of Northern Virginia late Tuesday night, and the bulk of the white stuff is expected to fall around the region between 2 p.m. and 9 p.m. today, said Calvin Meadows, a meteorological technician at the National Weather Service office in Sterling.

The NWS is predicting a total accumulation of 4 to 8 inches in the District before the snow ends Thursday morning. However, Meadows said that forecasters are "fairly uncertain" about the totals because of inconsistencies in prediction models.

Public schools in the area, as well as federal government offices and most local government offices, are closed for the day. Metrorail is running a normal schedule, but some bus lines are not running, have detours or have limited service. VRE trains are not running on Wednesday, and MARC is providing limited service .

"The best thing the people in the city of D.C. can do is stay off the streets," Mayor Vincent Gray said at a news conference this morning. Delivering an update on the state of the storm, he said, "Last I heard, no power lines down. I hope it stays that way."

There were some power outages in the area, though, most of which were in Northern Virginia. As of 9:55 a.m., Dominion power had about 12,500 Northern Virginia customers without power. But Pepco had only reported six active outages.

Meadows said the storm is caused by a strong low-pressure system and moisture off the ocean. The low-pressure system's center was in central-eastern North Carolina on Wednesday morning, and over the course of the day it is expected to move off the Tar Heel state's coast and then curve northeast toward New England.

"That's the favorite track for Washington to get major snowstorms," Meadows said.

A winter storm warning is in effect in the Washington region through 3 a.m. Thursday, when the snow is expected to stop falling. This type of warning is issued when forecasters expect a significant amount of snow that makes travel hazardous.

Meadows recommended that people only travel if there is an emergency. If people have to drive, they should dress warmly and keep food, water, a flashlight and a blanket in their vehicles.

"I wouldn't be out there unless I absolutely have to," Meadows said.

The many flight and train cancellations around the area have left many travelers stranded.

In Washington's Union Station, Roma and Perry Carpenter were trying to get home to Howard, Ohio to take care of their cows. Their Amtrak train to Cincinnati had been canceled because of trees on the train tracks.

"We have cows at home that we have to pay someone to take care of, and he's getting married on Saturday," Roma Carpenter said. "So we've got to get home."

Without other transportation options, they were expecting a two-day stay in a hotel in D.C. before they could take another train to Cincinnati on Friday.

"We tried to rent a car -- it was $580 to rent a car one way," she said. "So we still don't have many answers yet, but looks like hotels are getting slim to none right now... It hasn't been the best experience."

With so many people off work and school, some locals have time for fun. But a giant snowball fight has been delayed. The Facebook group Official Dupont Circle Snowball Fight, 2013 Edition has postponed a planned snowball fight for at least a few hours, while organizers wait to see if more snow will start sticking to the ground.

One commenter joked on the event's page, "Rainball fight?"

Staff Writers April Burbank and Eric P. Newcomer contributed to this report.