Amid heightened security concerns at the Capitol, a winter pastime is interrupted.

As inches of snow pile up during Washington’s biggest winter storm in two years, there is one place that won’t be seeing any snowball fights.

The Capitol grounds, one of the best spots in the city for sledding, are now off limits, another reverberation of the rampage there on Jan. 6. The city’s schools are all virtual on Monday; schools had been slated to reopen to some students in person but closed because of the weather.

Representative Eleanor Holmes Norton, the District of Columbia’s nonvoting House delegate, has urged the Capitol Police to allow the tradition to continue this week. The activity could be done safely, Ms. Norton said in a statement on Saturday, “by allowing only children and adults accompanied by children” into the area.

But a Capitol Police spokeswoman, Eva Malecki, citing the current security concerns and the city’s coronavirus restrictions, said it could not be permitted.

While a rule against sledding on the Capitol grounds has been in place for decades, it was rarely enforced until after the terrorist attacks on Sept. 11, 2001.

Ms. Norton has pushed for sledding to be allowed on the grounds for years; she first succeeded in slipping a pro-sledding provision into the omnibus spending bill in 2016.

The previous year, Washingtonians held a “snow-in” at the complex to protest the rule.

The ban has been revived at another moment of heightened tensions. Instead of children making snowmen and snow angels, visitors to the Capitol complex these days are greeted by seven-foot-tall, unscalable fencing that went up after the riot.

The acting chief of the Capitol Police, Yogananda D. Pittman, is calling for “vast improvements” to security on the Capitol grounds after the attack, which injured nearly 140 police officers and killed an officer and a member of the mob.

Chief Pittman, who took over the department when her predecessor resigned days after the riot, said that experts had argued for greater security measures for the Capitol even before the Sept. 11 attacks.

But in a trying year, Ms. Norton said, the sledding tradition was one joy that should not be erased.

“Children across America have endured an extremely challenging year,” she said, “and D.C. children in particular have not only endured the coronavirus pandemic but now the militarization of their city, with the hostile symbols of fences and barbed wire. Sledding is a simple, childhood thrill. It is the least we can allow for our resilient children this winter season.”