Last week's storm dropped about 100 inches of snow on some peaks, allowing some resorts to open terrain that they normally don't open until after New Year's.
Forecasts for Saturday call for four to eight more inches of snowfall in the Sierras.
That, said one resort spokeswoman, is just "the icing on top of the cake."
Squaw Valley already has a storm total of 99 inches and cold temperatures have kept the snow firm, said spokeswoman Amelia Richmond.
"We've never had this much snow for opening," Richmond said. "The last time anyone I've been able to talk to can remember this much snow before Thanksgiving was 1973."
Sierra-at-Tahoe and Alpine Meadows both reported storm totals of over 100 inches of snow, virtually all of which fell last weekend. As a result, slopes are in mid-winter form.
"Top to bottom, the entire mountain essentially is open on the first day of operation," said Kirstin Cattell, spokeswoman for Sierra-at Tahoe. "That is very rare.
"We pretty much went from looking at dirt and rocks to you can't find your car if you didn't move it for a day," she said.
The heavy snowfall allowed Alpine Meadows to open today, said spokeswoman Rachael Woods. At its midmountain snow stage Alpine Meadows took in 105 inches from the storm, Woods said.
"Terrain we'd expect to have open by Christmas or New Year's is open today," she said. "It's a banner day."
The National Weather Service forecast for Saturday calls for snow during the day and into the evening, easing off by Sunday morning.
Temperatures are forecast to be in the low 30s on Saturday, fall below 20 degrees in some areas near Lake Tahoe at night, and return to the high 20s on Sunday.
Farther south, near the Kirkwood Mountain Resort, snow showers might last into Sunday.
The Kirkwood resort is reporting a base of 73 inches and 85 percent of its trails open. The last time the resort opened for Thanksgiving was in 2004, said retail manager and buyer Carolyn Reuter.
"We have plenty of snow and we're opening lifts every day," Reuter said. "Our prognosis is good."
