Traffic on Baron Cameron Avenue has been jammed for hours Jan. 26, 2011, as heavy snow blanketed the Washington area. (Jahi Chikwendiu/WASHINGTON POST)

As the D.C. region’s snow generals prepare for the winter to come, they often wind up re-fighting the last war.

They try to learn lessons from whatever horror befell commuters the previous year. That’s why our preview for last winter focused on adjustments made after the winter of the big blizzards. And it’s why this year’s preview highlights lessons learned from last winter’s single significant snowstorm, the one that shut down the region on the afternoon and evening of Jan. 26.

But winter history rarely repeats itself, at least not right away. Commuters should remember the lessons of Jan. 26, just as the highway departments and personnel officers do, but long-range forecasts for this season suggest that we could be in for a mix of weather experiences.

Quandaries for deciders

Dean Hunter, deputy chief for facilities, security and contracting at the federal Office of Personnel Management, knows about the mix that the 300,000 federal workers in the D.C. region might confront.

For about four years, he has been a key participant in the gigantic 3 a.m. conference calls that draw together scores of federal and local officials. The officials state their information about approaching storms and express concerns about roads, rails, sidewalks, offices and schools.

The calls influence decisions about deployment of highway equipment, the opening or closing of schools and — in Hunter’s case — the status of federal government offices.

I presented him with a range of weather scenarios, from the certainty of blizzard conditions affecting the morning commute to the possibility of freezing rain affecting the afternoon commute, thinking that he could define a sliding scale of winter decision making from easy to difficult.

Hunter smiled. “They’re all difficult,” he said. That blizzard, for instance. It might be an easy call to tell federal workers to stay home before the storm hits. But afterward, when do you bring them back? He recalled a difficult day of commuting during the blizzard year when federal workers returned to their offices, but the roads and rail systems were not completely ready to receive them.

And quite often, there’s no regionwide weather. The decision makers may be talking about a storm that will bring heavy rain to Southern Maryland and ice to Loudoun.

Jan. 26: What went wrong?

The problem on Jan. 26 wasn’t with the forecast. Snow arrived in late afternoon, just as forecasters said it would. And it got heavy very quickly, just as they said it would.

In anticipation of that, federal workers were allowed to leave two hours before their staggered shifts ended. So there should have been a steady flow of outbound commuters before the storm struck.

Didn’t happen. It was Mother Nature vs. human nature. People looked out their office windows in midafternoon and didn’t see snow, so many kept working. They left when the first flakes fell, and by then, it was too late. They wound up sitting for hours in traffic jams. Some found themselves sitting next to plow trucks, also stuck in the traffic.

Changing federal policies

The Office of Personnel Management engaged in a communications blitz this fall to announce and explain its revised policy on the comings and goings of federal workers. Officials describe the approach as an “all hazards” policy that could cover earthquakes, hurricanes and attacks, but it also has applications for winter weather.

Federal workers could hear one of three new announcements from OPM:

●Staggered early departure, with a final departure time: Employees are told to leave their offices no later than a certain time.

●Immediate departure: Employees are told to leave right away in response to an event such as a fire, a power outage or an earthquake that causes building damage. (OPM officials point out that this action is most likely to be taken within individual departments.)

●Shelter in place: This is a last resort, possibly in response to a snowstorm, a tornado or an attack.

Likely scenarios

The early-departure announcement is most likely to be heard in winter weather. It could avert a repeat of Jan. 26 by giving federal employees a firm deadline for heading home. There would be little incentive to remain at work, which could, after all, subject workers to the shelter-in-place announcement.

Who wants to be stuck in the office without overtime? Some find the scenario draconian; others dismiss it as unenforceable.

But for all the attention it has received, shelter in place would have very limited uses during winter weather. One possible scenario: At 5 p.m., freezing rain shuts the 14th Street Bridge and makes the Capital Beltway in Bethesda impassable. OPM says stay in your office, or you’ll be stuck in your car. Under those circumstances, many employees probably would buy into the message.

Some travelers ask whether Metrorail would have the capacity to handle a dismissal with a final departure time.

Yes, said transit authority spokesman Dan Stessel. Metrorail can provide early peak-period service by bringing in more operators and sending out more eight-car trains. To do this well, he said, the transit authority needs about three hours’ notice.

Other preparations

Highway and public works departments in Maryland, Virginia and the District have become more aggressive about getting ahead of the storms and treating roads with de-icing solutions. They did that Jan. 26, but by the afternoon an early round of precipitation had washed away the treatments. It’s still a good plan and benefits commuters in many scenarios.

Still, Jan. 26 showed that aggressive planning and ample supplies of equipment have their limitations. The agencies involved in maintaining the transportation system need to be frank about what they can and can’t accomplish and about when commuters should just stay home.

Branco Vlacich, the Virginia Department of Transportation’s maintenance administrator for Northern Virginia, spoke that way when talking to local officials this month: “A minor event can have major impact on this region,” he said. The message to his own department was to be more aggressive in deploying for minor events. The message for commuters was that sometimes it’s better to telework and let the road crews accomplish their missions.

The evening commute on Jan. 26 would not have been so severe if many workers hadn’t gone to their offices in the first place. In the aftermath, federal administrators had another reason to provide employees with the resources and the authority to telework. More and more employees say they telecommute at least occasionally. But many more tell surveys that they would do it if they could.

Our collective ability to endure a winter storm involves planning at the personal as well as the organizational level. Bob Marbourg, the veteran WTOP radio traffic reporter who has guided commuters through many winters, said his wish for them is that they remember what they’ve been through, act accordingly, and cut decision makers some slack if they err on the side of caution.