Tisha Tutein understands that Ronald Reagan's body coming to lie in state is a once-in-a-generation, historic event. She's even looking forward to telling her kids and grandkids about it when she returns someday to her native St. Croix.

But that's the future. Today, all she really cares about is how the procession is going to muddle her drive home from Springfield to Upper Marlboro -- a trip that takes her right past the route that Reagan's body will follow from Andrews Air Force Base to the Capitol.

"Even though I am sad that Reagan passed . . . it's another day in traffic for me," she said. "I hate to say that, but yeah."

As the nation and world prepare for the drama of Reagan's funeral in Washington, transportation officials and drivers are trying to deal with traffic issues that include the closing of numerous roads in the District, Maryland and Virginia and thousands of visitors coming into town in the middle of a workweek.

To mitigate likely tie-ups, transportation officials are doing what they can to get the word out that people should take mass transit, take off work if they can and, by all means, steer clear of processional routes beginning about 5 this afternoon, when Reagan's body is to arrive at Andrews.

The tentative route goes from Suitland Road to Suitland Parkway, onto Interstate 295 north to the 11th Street bridge. From there, the procession will take Interstate 395 south into Virginia to the George Washington Memorial Parkway north and come back into Washington at the Memorial Bridge before moving to Henry Bacon Drive and Constitution Avenue NW. Intersecting roads will be closed as the motorcade passes. At 16th Street and Constitution, the coffin will be placed on a horse-drawn caisson. The processional will then take Constitution to the Capitol.

District police cautioned in a statement announcing the route that it could change "with little or no notice."

District officials also said Constitution will be closed from 3 to 9 p.m. today between 23rd Street NW and the Capitol, including the 12th and Ninth Street tunnels and all cross streets. Inbound traffic on the Roosevelt Bridge will be diverted to the E Street Expressway.

Tomorrow, officials expect thousands of people to come into the city to view Reagan's flag-draped coffin in the Capitol Rotunda, again straining downtown roads. On Friday, Reagan's body will be moved through town at 10:30 a.m. from the Capitol to Washington National Cathedral before heading back to Andrews at 1:15 p.m. for burial in California. A route for that trip has not been announced.

Transportation officials continued to plan for any circumstance, knowing that routes can always change. "We're obviously preparing for the event of the procession heading in any direction," said David Buck, a spokesman for the Maryland State Highway Administration.

Buck and other officials advised drivers to take Route 301 or the western half of the Capital Beltway tonight to avoid encountering delays near Andrews.

Preparation continued yesterday and included calling off all construction work that would cause lane closures, including on such major projects as the Woodrow Wilson Bridge and Springfield interchange, mobilizing extra emergency patrols and adding personnel. Mobile road signs and radio stations across the region will direct drivers to alternative routes. And HOV lane restrictions in Virginia have been lifted for Friday.

Federal and city workers will have Friday off, keeping many people away.

Driver and trucker Web sites advised big rigs to avoid the "significant traffic congestion" expected in the Washington region, a message that will be echoed on CBs, in truck stops and at gas pumps across the East Coast.

Metro officials said they plan normal service all week, including Friday. Metro declined a request by the U.S. Park Police to keep the subway running all night tonight and tomorrow because it would have prevented the transit system from doing needed maintenance on rail cars and track.

Instead, Metro will operate free shuttle buses between Robert F. Kennedy Memorial Stadium and the Capitol every 15 minutes from 11:30 p.m. today to 6 a.m. tomorrow. It will repeat that service during the same hours tomorrow night into Friday morning, spokesman Ray Feldmann said.

Parking at RFK Stadium will be free and will be monitored by D. C. police. An exact location for pickup and drop-off had not been determined by late yesterday.

Transportation officials were at a loss to think of a comparable event. The closest, they said, was the visit of Pope John Paul II in 1995, when parts of the Baltimore-Washington Parkway and Interstate 95 were closed for his motorcade to go from Baltimore-Washington International Airport to Camden Yards. Officials were in the dark about which routes would be taken for that trip, but roads were nearly empty as drivers stayed away.

But that was a one-day event on a Sunday morning.

Rita Gaines, who drives from Germantown to New Carrollton every afternoon, said this would be different. Although she should be out of the area before Reagan's body even touches down at Andrews, she's braced for a frustrating drive home because "there's a backup every day" and "because of this event there's going to be extra chaos and confusion."

The situation is particularly vexing for companies whose business it is to zip back and forth across the region. David Guernsey, president and chief executive of Chantilly-based Guernsey Office Products, said his business will grind to a near halt for the remainder of the week. He has encouraged some employees to take vacation time, and the company has called customers to put off deliveries until next week.

"To the extent we can delay until Monday, we'll delay until Monday," Guernsey said. "There's just no fighting through this. It's going to be brutal."

Staff writer Lyndsey Layton contributed to this report.