An atmospheric river will combine with a low pressure system to give both the Sierra and valley a good chance for snow on Sunday and Monday. It will be dangerous to drive through our mountain passes during the storm, especially on Sunday. It will be slick in Reno at times too, but not during the entire duration of the storm, all depending on your elevation.
A Winter Storm Warning is posted for the Truckee Meadows as well as the Sierra, because impacts will be strong enough for people to take precautions and avoid driving. A warning is worse than an advisory. The Winter Storm Warning for the Truckee Meadows starts Saturday night at 10pm and goes through 10pm Sunday night. The Winter Storm Warning for the Tahoe Basin goes through 10am Monday Morning, and 4am Tuesday morning at Donner.
The snow bands will initially come out of the south and ride along the atmospheric river. This means Carson City and Minden will see snow before Reno. It will be cold enough for accumulating snow below 5000’ early Sunday morning through 12pm, but after that temperatures will be warm enough in the lowest elevations for some rain to mix in and roads to become more wet.
Places like the North Valleys will see pure snow through late Sunday morning before turning slushy around 3pm, but still slick. As temperatures cool, there will be another opportunity for accumulating snow in the lower elevations after dark on Sunday for a couple hours. The bands will start to break a part by 9pm Sunday. It will be very icy Sunday night into Monday morning. There is also a chance for more scattered snow showers on Monday.
Snow totals will vary greatly in the Truckee Meadows, depending on elevation. Locations below 5000’, including near the Reno Airport, mid town, down town, South Meadows, and Sparks will see between 3-6 inches of snow. Most of it falling by 1pm Sunday. Locations at or above 5000’ including the North Valleys, Galena, higher part of Arrowcreek, Somersett, Verdi, Virginia City, and Spanish Springs could see between six and twelve inches. Caughlin Ranch will see between six and 10 inches of snow by early Monday morning. Same goes for northwest Reno near the university. There will also be more snow on our yards than the roads.
This will be a great storm for our snowpack and water supply. Feet of snow will fall at the crest between late Saturday night and Tuesday morning. Especially in Mono County, south of Tahoe. Tahoe could see between 10 and 20 inches of snow, with more snow falling on the California side than the Nevada side, but both will see a good amount of snow. Between one and three feet of snow will fall at Donner and the Central Sierra Snow Lab with this storm. While the first part of the storm will favor the California side of the Sierra, the second half of the storm on Monday and Tuesday will favor places like Mt. Rose as our the flow comes more out of the east. Heavy snow with rates reaching a few inches per hour will lead to treacherous driving conditions along our mountain passes on Sunday. Road closures are possible.
The snow will be Sierra cement, with high water content. This will certainly help our water supply and snow pack, putting us closer to average for the season. Great for building snowmen too.