Will it rain or snow in Tahoe or Sacramento on Thanksgiving? It’s too soon to tell

If you’re hoping to plan out your Thanksgiving travel accordingly with the weather, it might be too soon to set anything in place.

Tahoe-area news outlets reported Monday that there’s a chance a “weak-to-moderate atmospheric river” bringing wet weather to the Pacific Northwest from Nov. 22 to Thanksgiving on Nov. 24, but it’s still too early to know exactly when it will hit — or how strong it will be.

Scott Rowe, a meteorologist with the National Weather Service in Sacramento, said that while the agency does have tools to assess potential atmospheric rivers, it only officially forecasts out the next seven days.

Rowe said Tahoe’s forecast is mostly dry for this week, with limited chances of rain through to Friday. There is a 20% chance of wet weather, he said, at the tail-end of the seven-day forecast, on Nov. 21 and Nov. 22.

There may also be some moisture from Nov. 27 to Nov. 29.

“But confidence is very low at that point in time,” Rowe said Monday, “since we’re talking 11 to 14 days out in the future.”

While an atmospheric river, which refers to columns of water vapor in the atmosphere that typically brings rain and snow, is possible, both Rowe and climate expert Paul Ullrich caution against the definitive.

“10 days is pretty much at the periphery of our ability to forecast the weather,” said Ullrich, a professor of regional and global climate modeling at the University of California, Davis. “While there probably will be an atmospheric river, it’s too early to say where it’ll end up and how strong it’ll be.”

The NWS seven-day forecast for Sacramento also shows cold but dry weather for Tuesday to Nov. 21.

“At this point, the atmospheric river doesn’t exist,” Rowe said. “So we can’t call it that. It’s just the possibility of the return of some moisture at that point in time.”

This story was originally published November 15, 2022 at 12:41 PM.