As the window for snow closes, here’s 713 inches that Philly missed

For only the fourth time in 138 years that the government has been keeping score, April has arrived with Philadelphia having received less than an inch of snow for an entire season.

Even the computer models have stopped hallucinating about snow as the region makes a seamless transition to the thunderstorm season.

If you’re wondering what happened to the snow during the winter of 2022-23, a whole lot of it fell officially upon the legendary Donner Pass in the Sierras, a venue for at least two of history’s most famous disasters.

Those outsize snow totals you may have heard about out West are not apocryphal. It turns out that some brave souls from the Berkeley University Central Sierra snow lab actually have been out there measuring, reports Andrew Schwartz, the lab’s lead scientist and manager.

As of Friday, 713 inches of snow had been documented at the Donner Pass site — its second-snowiest season on record — or about 2,400 times more than the 0.3 inches Philadelphia has received as it calls it a winter.

But as meteorologists have been pointing out, what hasn’t happened in Philly and along the I-95 corridor is very much related to the Sierra snow blitz.

For a variety of reasons, all winter the upper-air patterns have been aligned to drive those atmospheric rivers and chill into California, while depriving the East Coast of any sustained cold or major snow-makers.

When high pressure builds off the coast of northwestern North America, it tends to spare the West of storms and drives cold air eastward. Winds circulate clockwise around highs, so areas to the east of the center get cold winds from the north.

This winter, the high pressure has been centered offshore, said Schwartz, and that has been an invitation to mayhem in the West. As so often happens, the East experiences the mirror opposite. The atmosphere has only so much cold air to distribute — and a bit less than it used to have.

“You just keep missing the snow,” said Dave Dombek, senior meteorologist with AccuWeather Inc.

How does one measure 713 inches of snow?

Since 1946, Berkeley lab staff members, and on occasion students, have measured daily snowfall and water-content amounts, armed with rulers, sample tubes, and scales.

Measurements are taken twice a day, at 8 a.m. and 4 p.m., atop a snow board, which is cleaned off for the next batch assault. The tubes and scales are used to weigh the snow to estimate water content, which is critical since the snowpack is a reservoir for so many Californians.

The current snowpack is down to 14.5 feet deep, Schwartz said Friday, and holds 6.1 feet of water.

Not quite, says the government’s U.S. Drought Monitor. Parts of Southern California remain in “moderate” to “severe drought.”

“The drought over the last several years was so severe that even this winter hasn’t completely alleviated it,” he said.

The situation has improved substantially, however. A year ago, close to 70% of the state was in severe drought. That’s down to just under 10%.

With rising global temperatures, Schwartz said, the lab has seen a trend for shorter snowpack and more instances of snow changing to rain in the winter months.

This was not the snowiest winter: That distinction belongs to the 1951-52 season, when the total reached 813 inches.

It was during that winter that over 200 passengers on a train bound for San Francisco became stranded for three days about 15 miles west of Donner Pass during a blizzard.

The pass, of course, gained its name from the 1846 tragedy involving the 81 California settlers in the Donner Party. Snow forced them to spend a winter on the east side of the mountains, and only 45 of them survived.

Nothing that catastrophic happened this winter, just 60 feet of snow.