Summary:

Cloudy and cool today with highs in the 30's.  A weak splitting system may push some light snowfall into the region this afternoon and overnight.  Not expecting more than a dusting of snow.  Then on Tuesday a more consolidated storm pushes in that could bring 3-6 inches to the Tahoe basin and 6-12 inches to the mountains.  Then on Wednesday another weak storm could bring an additional 2-4 inches to the Tahoe basin and 3-6 inches to the mountains. 

We could see some light snow Thursday before a break in the action Friday.  Then more light snow possible over the weekend.   High's should remain in the 30's at lake level and 20's on the mountains through the week.  The winds will gust up to 25 mph at lake level Tuesday, up to 50 mph on the mountains, and 80+ mph on the highest exposed ridges. 

Details:

Not too many changes to the forecast this morning.  Still expecting 3 weak storm systems to move through this week bringing us light amounts of snowfall.

The first system has been bringing rain to the coastal areas of CA over the past 2 days but the precip has not progressed Eastward.  That will change today as it begins to push East but falls apart as it reached the Sierra this afternoon and overnight.  We should see some light snow showers break out later today into tonight, but most of the light accumulations should stick to the crest where an inch or two could accumulate.  Here is the forecast through tonight.

The 2nd storm for Tuesday holds together and brings in more moisture.  Still it is a weak storm with more wind than precip.  The heaviest snowfall should fall during the day Tuesday.  The GFS continues to be wetter than the other forecast models.  The European model is a little wetter this morning, but still about a half in inch drier across the Tahoe basin compared to the GFS.  Here is the snowfall forecast for Tuesdday averaging the 2.

Tuesday night we should see a brief break in the snowfall before a 3rd storm moves in Wednesday.  This storm is holding together a little better this morning on the latest model runs.  It is weaker than the Tuesday storm with less precip.  Here is a look at the snowfall forecast for Wednesday with the 3rd system.

We could see some light snow Thursday as the center of the low responsible for the Wednesday snow moves through CA.  The models are taking it to our South so not expecting much snow as of right now but we will watch that track for Thursday.  Snow levels stay well below lake level through the week.  Here is a look at the WPC's blended model forecast for total precip by Friday.

Here would be the total snowfall for the 3 storms not including an inch or two that could fall Thursday.

Those amounts might be worthy of hyping if falling in one day but this is over 3-4 days.  Still, it is fresh snow and it is falling in January finally which is noteworthy.  Below is a comparison of the GFS total precip through Tuesday compared to the NAM.  See the blue into the Tahoe basin on the GFS and only the green on the NAM?  The NAM and Canadian forecast models are even drier than the European model for this week, so we may want to lean towards the lower end of the forecast above.

GFS

NAM

Another weak storm may try to push in over the weekend but the trend on the models is for the storm to split apart and not bring much precip.

Long-Range:

The GFS was starting to show some bigger storms next week but I didn't want to hype it with the European ensembles showing the trough in the Eastern Pacific further West for next week over the last few days.  Today the other models are trending that way.

Look at the pattern this week on the CFS v2 ensembles.

and now for week 2...

It is looking more and more like the European forecast and the GFS is trending that way as well.  The stronger storms moving into the Eastern Pacific next week would have a harder time pushing into the ridge over the West next week.  The European and GFS long-range operational runs show 2 storms reaching the Tahoe basin next week in  much weakened state next Tuesday and Thursday.  So the storms may continue but continue as weak storms.

What is interesting to me is that when reading some other weather sites and the comments they totally disregard the European model and ride the GFS bandwagon even though the European model tends to outperform the GFS in the long-range.  People were mocking the Euro assuming the strong storms for next week had to be right with the strong El Nino.  Maybe it will trend back that way but right now the other models are trending towards the Euro.

This El Nino is strong but the SST pattern is different than 83 and 98.  This El Nino did become the strongest on record for region 3.4 but it is also centered further West in region 3.4 and not as warm further East as as it was in 98.  Last year we saw how the more West centered El Nino favored a trough in the East and a trough further West in the Eastern Pacific like the pattern above for next week.  

Also what is interesting is that in the Fall I posted several of the climate models that are showing the trough in the Eastern Pacific further West this Winter than during the 97/98 event.  But many of the weather sites jumped on the CFSv2 bandwagon that showed the trough further East nearer the West Coast than any other model.

Maybe that will be how this plays out as we get later into the month and beyond with big storms for CA.  But for now the storms are weak and the trend for next week is the trough in the East and the trough in the Eastern Pacific further West, with weakened storms as they encounter the Western ridge.  I guess my point is that I am not surprised by the trend for next week if it continues, but I am surprised by the amount of forecasters who disregard all the other models besides the GFS in the short-range and the CFSv2 in the long-range.  

I'm not a climate expert just snowfall forecaster for Tahoe.  It does continue to look like the trough could push closer to the West Coast around or just beyond mid-month with stronger storms finally pushing in.  Let's hope that trend continues...

Stay tuned...BA