As of 1:40PM, The next weather system that will affect our area has spread precipitation south to the Bay Area. However the band of precip has yet to reach the sierra, north or south.  Snowfall projections are now on the low end of the forecast with a foot expected on the sierra crest by Friday night.  The NWS is not issuing a winter storm warning as snowfall is expected in the 3 to 6 inch range in town with 1 to 4 inches along the 395 corridor. High temps will be falling through Saturday with highs in the upper 20s by then….Lows in the teens….

 

WX Discussion:

This weather system is highlighted by a split in the flow in the long wave pattern along about 40 north with main precip band to the north, then weakening to the south. Main energy will dive south into Northern Baja. This sort of storm is reminiscent of many during drought years….  Additionally, the behavior of the systems in the models from 5 to 7 days out vs within a few days of the event suggests that the global models do not have a handle on the overall pattern, over the eastern and central pacific. Thus there is little confidence beyond 3 to 4 days.   Case in point; there is another very significant storm showing up, from the WNW in the 18Z GFS model run today 1/18/18,  This is for the period next Wednesday the 24th through Thursday night.  The EC has it as a very cold NW or inside slider.  In my opinion neither model has a handel on the final outcome for that period. The Dweebs can not wait until the QBO switches from Negative to Positive later this Summer or Fall of 2018. In my opinion, this teleconnection along with others is partially responsible for the extreme dryness so far this Winter.

 

The Dweeber……………….:-)