California’s extreme winter weather just brought one of the Sierra Nevada’s crown jewels to a standstill — literally.
For the first time since the early 1990s, Lake Tahoe’s Emerald Bay has completely frozen over.
“We’ve lived in the Tahoe area for three years. I have never seen it freeze completely,” Kaytlen Jackson, state park interpreter in the California State Parks’ Sierra District, told SFGATE in a phone interview Friday. When she heard the bay might be frozen over, she headed there right away to get a glimpse.
It’s thought that Emerald Bay — known for its shimmering colors, Vikingsholm Castle and gorgeous mountain backdrop — was last completely covered with a sheet of ice in 1993 and 1989.
Before that, you’d have to go all the way back to the 1950s, Jackson said.
On the rare occasion that conditions are right, the glistening body of water is shallow enough to turn into a sheet of thin ice. Located about 12 miles north of South Lake Tahoe, the lake’s only inlet is estimated to be an average of 150 to 170 feet deep and 230 feet down at its deepest point right off Fannette Island.
“It’s fairly common for it to freeze to a certain extent, especially along the edges of the bay,” Jackson explained. “Every year I’ve lived here, I’ve seen it freeze to some extent. It’s uncommon for it to freeze completely like it is now.”
Winter temperatures at Emerald Bay State Park average from a high of 40 to a low of about 20 degrees. The bay is only known to completely freeze over “during extremely cold winters,” according to California State Parks. The National Weather Service showed temperatures well below freezing much of this past week, including a particularly frigid stretch Wednesday into Thursday at or near single digits — not including the wind chill. Two storms are hitting the region this weekend.
“The body of water is losing heat on the surface and once it loses enough heat, it freezes,” Jackson explained.
Emerald Bay in Lake Tahoe sees partial freezes every winter, but for the bay to completely freeze over is unusual. The ice is currently believed to be about 6 inches deep.
Courtesy of California State ParksOf course, Lake Tahoe itself has never frozen over. The huge freshwater lake is simply too big and too deep to do so, given its immense size and the region’s winter weather patterns.
Park officials are asking would-be visitors not to visit Emerald Bay for a sightseeing trip right now. The latest atmospheric river storm is slamming the Lake Tahoe area this weekend, creating dire road conditions with a major chance of flooding.
“[The ice] is not thick enough for folks to walk on. That’s very dangerous,” said Jackson, who observed evidence of avalanche activity and several downed trees when she was in the area Thursday. The ice is only thought to be about 6 inches thick.
Temperatures are expected to peak at about 40 degrees through the weekend, meaning Emerald Bay’s full ice coating may not stick around for very long.
A summertime trip is much better, Jackson added. Emerald Bay State Park’s many vistas and hiking trails make it a can’t-miss stop for Lake Tahoe visitors and residents alike. Emerald Bay was declared a National Natural Landmark in 1969, with its waters named “a special underwater area” in 1994 as part of Emerald Bay State Park.
“It is a sight to behold. Emerald Bay any time of the year is incredibly beautiful. About 3 million people visit Lake Tahoe every year,” Jackson said. “The vast majority of them are going to drive straight to Emerald Bay because of how beautiful it is. It’s just magical.”
