RENO, Nev. (AP) — No one really knows how much snow fell on the infamous Donner Party when pioneers were trapped atop the Sierra Nevada for months and dozens died near Lake Tahoe in the winter of 1846-47.

But this season has now entered the history books as the second snowiest in the 77 years of record-keeping at the Central Sierra Snow Lab, with more than 56.4 feet (677 inches, 17.2 meters) and no end in sight.

And there’s still a chance it could surpass the record of 67.7 feet (812 inches, 20.6 meters), set in 1951-52 when more than 200 passengers on a luxury train bound for San Francisco from Chicago, stuck for three days near Donner Pass west of Truckee, California.

Over the weekend, the “winter that doesn’t want to end,” as the National Weather Service in Reno said, surpassed the previous record No. 2 of 55.9 feet (651 inches, 17 meters), set in 1982-83. It was the second devastating blizzard season, best remembered for the avalanche that killed seven people at Tahoe Ski Resort on March 31, 1982.

Since December, a parade of atmospheric storms has dumped so much snow on the Sierra that Tahoe ski resorts have been forced to close several times.

The final day of the Nevada High School Cross Country Championships has been canceled. Roofs collapsed under the weight of the snow and schools were closed for several days. Interstate 80 has been closed several times between Reno and Sacramento.

“It started early and it seems to be continuing,” said Eric Sage, 45, of Sparks, who has experienced many big winters in Truckee but can’t remember one like this. “It’s piling up, big storm after big storm after big storm — boom, boom, boom.”

The official accountant is the Central Snow Laboratory of the University of California, Berkeley, founded in 1946 in Soda Springs, California, northwest of Lake Tahoe.

“In other years and years, we’ve seen stronger storms with higher snow water equivalents … but the relentlessness of this season probably makes it the most unique,” said Andrew Schwartz, the lab’s director and lead researcher.

More snow is forecast for the next 10 days, but no one knows what exactly spring will bring.

“Historically, some of our big seasons have continued to be active into late spring,” said Tim Bardsley, senior hydrologist for the National Weather Service in Reno.

Officially, the winter season coincides with the water year beginning on October 1 and ending on the following September 30. Sometimes snow continues to fall in the Sierra even in June.

To beat the 1951-52 record this winter would require another 145 inches (368 cm) to fall — unlikely, but not out of the question.

“Basically, there’s nothing to suggest that just because we’ve been so active, we’re going in a different direction,” Bardsley said. “I would almost say that the opposite is most likely.”

Several of the snowiest winters after March 15 accounted for at least one-quarter of the season’s total. The fourth snowiest winter of 2010-11 received 225 inches (572 cm) of the 643 total inches (1,635 cm)—or 35%—after March 15.

The Snow Lab has records dating back to 1880, based on measurements taken by the Southern Pacific Railroad. These unofficial measurements, taken near where the train stopped in 1952, show that more snow may have fallen in 1938 and nearly as much in the 1880s and 1890s.

The lab does not officially recognize these numbers because they were obtained from slightly different locations using a different methodology.

Mark McLaughlin, author of several books on Sierra history and Tahoe-area weather, accepts the railroad’s numbers and believes that the snow that fell in the Donner Parts in 1846-47 was similar to what fell in 1951-52.

In the first two weeks of November 1846, ten severe storms lashed the mountains with rain and snow. A monument at Donner Memorial State Park indicates that the snow was as deep as 22.5 feet (6.9 meters) before some of those stranded turned to cannibalism.

The third-ranked winter of 1982-83 followed the season when Tahoe’s deadliest avalanche hit Alpine Valley south of Truckee. About 90 inches (228 centimeters) of snow fell in four days, leading to the disaster.

The 1960 Winter Olympics, the first to be televised, put Lake Tahoe on the map after the world saw the snow-capped mountains surrounding the alpine lake with its turquoise waters. But the winter itself got off to a slow start, and Olympic officials were panicking in the weeks leading up to the games.

“There was no real snow until New Year’s, and the Olympics were in the third week of February,” McLaughlin said. “Then the storm door opened and it snowed and snowed and snowed. There was so much snow that no one could ski on the mountain.”

Author Peggy Townsend and her husband, the parents of professional skier Cody Townsend, said they were inundated with piles of snow when they arrived at their cabin in the Olympic Valley area near the base of Tahoe Ski Resort last month. They had to park on the road and dig through 10 feet (3 meters) of snow.

“We’re going to have to dig three or four times a day to get to the woodshed,” Peggy Townsend said. After four days, they had had enough.

“When the snow broke,” she recalls, “we just said we were going to get out of there.”