Northstar picked up 21 inches on top in the past 24 hours and 10 inches at the base. That brings the 4 day total to 32 inches and the season total to 279 inches. The heavy snow will stop this morning and then snow showers will kick in later in the morning as the really cold air associated with the core of the low coming down the coast arrives. Only expecting another 2-4 inches today from the snowshowers.
Temperatures will fall throughout the day today and we will be in the single digits by tonight. Highs will only be in the teens Thursday and Friday and then the 20's for the weekend. Overnight lows will be in the single digits.
A cut-off low, which just means it is split off from the main jetstream so nothing is steering it, will move down off the coast of CA. If you are a frequent reader of this blog or another weather discussion you know that cut-off storms are very unpredictable and their track can make big differences in precip amounts. If you split the models the track will be just off the coast of CA. That means the storm will be able to pick up more moisture off the ocean, but the question is does it come close enough to deposit that moisture as snow over Tahoe. Basically we could see anything from no snow to a foot of snow depending on a small variance in the track of the storm down the coast.
Right now models show us getting a total of around .5 - .75 inches of liquid over the course of Saturday and Sunday. That seems small, but we will have snow ratios of 15:1 during the day and 25:1 at night, so split that and that's 10-15 inches on the mountain. It's risky making a snowfall prediction with a cut-off. We will have to watch the exact track as it happens, but i will update the models predictions the next few days. Maybe we'll get lucky!
Next week the ridge in the Pacific is sitting around 140w and is close enough to us to keep the storm track to our North into the Pacific NW. The models are beginning to agree there will be retrogression of the ridge out to around 160w North of Hawaii which would open the storm door. The question is when. The Euro wants to do it by the 7th and the GFS says not till the 10th. They have both been consistent, so the question remains whether we have 5 or 8 days of quiet weather after this weekend. If we see retrogression to that postion then we should see cold storms hit every couple of days into the middle of January. The La Nina signal takes over here in January so we should see the colder air and storms from the NW continue into February.
People in the media are saying that we should be dry this year because it's a La Nina but that is not true. We have strong La Nina conditions currently and it is forecast to stay strong through the winter. In the past 60 years we have had 4 strong La Nina years: 55-56, 73-74, 75-76, & 88-89. 2 of those 55-56 & 73-74 had above average precip for most of the state of CA including Southern CA. 73-74 came off a strong El Nino the previous year like we did this year & Donner Summit received 125% of average snowfall that year. That is why it is my analog year and one of the reasons I predicted 125% of average snowfall for us this year. Maybe people just can't remember that far back but they should do some research. Don't worry I will keep you accurately informed. BA