Lake Tahoe filling up, and the water level is back to the natural rim

Lake Tahoe is swelling after a rainy October and November: Lake Tahoe reached its natural rim after weekend storms dumped 12.5 billion gallons of water into the lake. Photo taken from the Heavenly ski resort web camera on December 14, 2016. less Lake Tahoe is swelling after a rainy October and November: Lake Tahoe reached its natural rim after weekend storms dumped 12.5 billion gallons of water into the lake. Photo taken from the Heavenly ski resort ... more Photo: Heavenly Ski Resort Photo: Heavenly Ski Resort Image 1 of / 19 Caption Close Lake Tahoe filling up, and the water level is back to the natural rim 1 / 19 Back to Gallery

The Sierra Nevada is getting soaked this year, and Lake Tahoe is one of the biggest beneficiaries.

The sixth-largest lake in the United States, which straddles California and Nevada, reached its natural rim after weekend storms dumped 12.5 billion gallons of water into the lake. A trickle is now flowing through the dam and into the Truckee River.

This is a huge milestone for a body of water that has flirted with record-low levels amid an ongoing drought.

RELATED VIDEO: When Tahoe was at its lowest water level in years.

Tahoe's water level reached 6,223.04 feet on Tuesday afternoon.

At the same time last year, the level was a full 1.5 feet lower. This was a disappointment in an El Niño year when storms expected to bring record-breaking snow and rain delivered only average precipitation, filling some reservoirs but making only a small dent in California's drought conditions overall.

This year is showing more promise as storms continue to batter the Sierra Nevada. Tahoe City, a town that sits on the lake's north shore, saw its wettest October in recorded history this year.

U.S. District Court Water Master Chad Blanchard says 9.04 inches of precipitation (rain and snow) were recorded in October while the average is 1.76.

"That was the largest October for precip since we had records back to 1910," Blanchard said.

Across the Northern Sierra, October and November marked the wettest start to a water year in 30 years, according to data collected on total liquid from rain and melted snow by the Department of Water Resources at eight stations in the Northern California mountains running from the Cascades to the northern Sierra.

Another storm, predicted to be the biggest of the season, is expected to wallop Northern California on Thursday, reaching its tendrils across the Sierra and dumping more snow and rain. Lake Tahoe will continue to rise and the spill into the Truckee River will likely surge.

But the weather forecast beyond this weekend is unknown and unpredictable. "We're in a neutral year right now and the forecast is still for a weak La Niña to move in,"said Jim Andersen, a meteorologist in the National Weather Service's Hanford office. "This means the storm track could shift father north into Oregon. If that does happen, we could have a drier January and February. But that's only one index. One little factor in the bigger picture."