A weak storm is going to pass over the area tonight into Wednesday morning. Every model is set on squeezing out 1-3 inches of snow at best over Tahoe from this storm. Maybe 2-4 on the summit from the lift and the extra fluff from temps in the mid-20's.
Plenty of cold air behind this storm to keep the snow guns firing. Right now the ridge in the Pacific is out around 140w. It is going to stay there for a while, but start moving to a position off the Pacific NW by this weekend instead of off of CA. This will keep the entire West Coast blocked from storms. With the ridge off the coast however, it does allow the storms to dive down it's East side into the Great Basin and the Rockies. As they do they drag down shots of cold air into Tahoe. We will warm up a little bit Friday and Saturday before a weak shot of colder air on Sunday and then a stronger one by the middle of next week.
In La Nina falls it can be normal to have warmer and drier than normal weather in November, so we should be happy that it will at least be cold enough to make snow at night. Eventually as we go into real winter the ridge will move even further North in the Pacific and the stronger jetstream will come under the ridge into the West Coast. Winter this year should really get cold and snowy Jan.-March. Until then we should hope for the shots of cold and the occasional snow. Remember the last La Nina of 07-08 we didn't get big snow until the first week of Jan., but that was a monster storm and then it didn't stop snowing for around 6 weeks.
A couple things that we do have to watch the next couple of weeks that may mess with the pattern and increase our chances of snow are the PNA going negative and the MJO progressing into the Western Pacific. Right now the long-range models just have shots of cold from the North with light snow like tonight, but that could change. Stay tuned........BA