By ccrossen | December 11, 2012
Ok. Looks like winter is finally ready to arrive at all elevations. Coverage and skiing above 7,500-8,000′ has been great. It has stayed cold up high and the snow has been holding nicely. Variable, to be certain, but there is a lot of snow in the upper elevations - it looks like February up there. The good news snow is on the way, and the weather pattern looks stormy/active for the next few weeks at least.
We have a series of storms coming in this week, starting tonight/Wds early AM. We have a Winter Weather Advisory for Tahoe, and it looks like a cold storm, with accumulations of 4-8 inches at Lake level and 12+ on the Crest. Friday we have snow showers, an inch or two, and then Saturday evening/Sunday we get the main mover, with the potential of a couple of feet in the high country with up to a foot in town. This last system is a cold one, and snow-ratios should be rather high.
All told, we have
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
NO MAJOR CHANGES TO THE LONG TERM FORECAST. AS THE UPPER RIDGE OVER THE PACIFIC RETROGRADES TO THE WEST, THIS WILL KEEP THE STORM TRACK
PUSHING INTO THE WEST COAST THROUGH THE WEEKEND. WE ARE EXPECTING PERIODS OF COLD AND SNOWY WEATHER DURING THE LONG TERM, ESPECIALLY
IN THE SIERRA. MODELS CONTINUE TO BRING A WEAK WAVE THROUGH NORTHERN CA ON FRIDAY, WITH A SLIGHT CHANCE OF SNOW SHOWERS MAINLY NORTH OF TAHOE. INTERESTINGLY ENOUGH, THE 06Z GFS IS NOW COMING IN WITH HIGHER QPF NUMBERS FOR THIS FRIDAY WAVE. BIG DIFFERENCE HERE, SINCE THE GFS HAS BEEN THE DRIEST OF THE MED RANGE MODELS FOR FRIDAY.
A COLDER AND MORE DYNAMIC SHORTWAVE MOVES INTO NORTHERN CA ON SATURDAY NIGHT. THIS STORM WILL CARRY ON THROUGH SUNDAY, WITH SNOW LEVELS DOWN TO ALL VALLEY FLOORS BY SUNDAY MORNING. QPF AMOUNTS HAVE BEEN PRETTY CONSISTENT IN THE ECMWF, SHOWING UP TO AN INCH OF QPF ALONG THE SIERRA CREST THROUGH SUNDAY (FROM LASSEN DOWN TO MONO COUNTY). THIS COLD SYSTEM WOULD LEAD TO VERY HIGH SNOW RATIOS, LEADING TO FAST ACCUMULATING POWDERY SNOW AND POTENTIAL FOR HEAVY ACCUMULATIONS IN THE SIERRA. SPILLOVER SNOW INTO WESTERN NV LOOKS GOOD TOO, AS WE`LL BE ON THE COLD, UNSTABLE SIDE OF THE JET.
HIGH PRESSURE BUILDS INTO THE REGION BY MONDAY, AS SHORTWAVE RIDGING KEEPS US IN BETWEEN STORMS. KEPT IN SOME CHANCES FOR SHOWERS AS THIS FORECAST HAS BEEN CHANGING FROM DAY TO DAY IN THE LONG TERM. A CONTINUED ACTIVE WEATHER PATTERN IS EXPECTED INTO NEXT WEEK, AS ADDITIONAL COLD WEATHER SYSTEMS DROP INTO NORTHERN CA/NV.