Saturday Sept. 27
A low pressure system slowly moving across California and into Nevada dumped snow on the higher peaks around the Tahoe Basin overnight and could bring flakes down to areas below 7000 feet this morning. About an inch of rain fell on favored locations while as much as six inches of snow is expected to accumulate above 8000 feet.
A band of precipitation currently over Nevada is forecast to move north and west this morning, bringing more rain and snow to the Tahoe area, with thunderstorms possible, before the low pressure core at the center of the storm eventually moves south and east and out of the area.
The low will begin moving out late today but we could still see some isolated showers in its wake on Sunday before things dry out.
A ridge of high pressure is expected to build near the coast early next week and then drift over the Sierra, keeping Tahoe’s weather dry next week.
UPDATE 4:30 PM: Don’t be fooled by the lull in the precipitation. The low pressure at the core of this storm system is still moving over the Sierra and is expected to drift south and east over the next two days. That’s going to mean cooler temperatures and more precipitation, especially in areas toward the southern end of the Tahoe Basin and further south. We could see several inches of snow over Carson, Ebbetts and Monitor passes and possibly even some snow at Luther Pass. The low should be moving out of the region by Saturday but even colder temps will move in behind it on Sunday.
Thursday Sept. 25
The first storm of fall is moving across California’s Central Valley this morning and heading for the Sierra.
The front is expected to move slowly eastward through the day, bringing rain to the Tahoe Basin mixed with smoke from the King Fire, which will be pushed over the Sierra Crest by westerly winds. Temperatures will drop behind the cold front but snow levels will remain very high, probably above 8500 feet.
The low pressure system is forecast to move through the Sierra late Friday or Saturday, but some scattered showers could linger through the weekend in the unstable air behind the low, mostly on the eastern slope of the Sierra and into Nevada. Between a half an inch and an inch of rain total is likely by Sunday along the Sierra Crest.
A ridge of high pressure will build behind the storm by Monday but a backdoor system — moving out of the Pacific, north and then south into Nevada — is expected to bring northwinds and cooler temperatures by the middle of next week, though any precipitation for Tahoe is likely to be very light at best.
Fall is upon us and the Geek is back with an eye on the sky and the upcoming winter season.
We hope you all had a great summer.
As we’ve reported in our newsletter, the forecasts for a strong El Nino that were floating around in the spring have faded, and while there is still hope for a moderate effect from above average temperatures in the Pacific, any El Nino we see this winter will not be strong enough to lead to a prediction of heavier than usual precipitation. So at this point the best crystal balls in the business are expecting an average winter, which really means it could be anything from very dry to very wet. We will just have to take it week to week and month to month and see how it pans out.
In the meantime a cold front is moving its way toward California and is expected to arrive on the coast by mid-week and in the Sierra by Thursday. Some light precipitation, mainly north of I-80, looks likely around Thursday or Friday, with snow levels above 8000 feet.
After that, two of the forecast models differ on how long the system will hang around once the front moves through. One of the models is showing a quick moving system that would leave us a dry weekend and temperatures rebounding a bit. Another model shows a lot of activity in the Tahoe area behind the front, with precipitation possible into the weekend.
We will keep our eye on the various scenarios and update you here about which one moves to the fore as the week unfolds.