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sierra cement
By ccrossen | February 24, 2010
Heavy wet storm descended upon Tahoe last evening and this morning, dropping up to a foot+ at 7,000′ with much more at the higher elevations. This snow is super-heavy, 20% water content, classic cement. Unfortunately, this snow fell on top on surface hoar, crust, and ice making for considerable avy danger, and lots of slides occurring everywhere - Squaw has seen almost every aspect slide big, e.g. West Face and Alternates all the way to the cat track. Avy debris and crowns everywhere. Backcountry is sliding as well. Thick stuff out there today. Snowed hard this morning, but the sun was out by 11:00. Very warm temps this afternoon into tomorrow and the weekend. Next storm system arrives Thrs - Friday and will be bigger than this one, especially down south, where they’re looking at another 2-3 feet by Sat AM. Thsi should be another warm system, with high snow levels and cement all around.
A FAIRLY DECENT SYSTEM ARRIVING FRIDAY INTO SATURDAY. WINDS TO INCREASE FRIDAY AFTERNOON AHEAD OF THE MAIN PRECIP SHIELD BUT DOESNT LOOK QUITE STRONG ENOUGH TO JUSTIFY WIND ADVISORIES. MODELS IN DECENT AGREEMENT WITH A FAIRLY WIDE MOISTURE PLUME THAT WILL BE FORCED TO BANK INTO THE SIERRA LATE IN THE DAY. THE FLOW IS MOST FAVORABLE FRIDAY AFTERNOON AND EARLY EVENING BEFORE THE BACKSIDE JET TRIES TO SPLIT THE SYSTEM SOUTH INTO SRN CA. THIS WILL TEND TO TURN THE FLOW FROM W-SW TO MORE SOUTHERLY…A LESS OROGRAPHICALLY FAVORABLE ORIENTATION FOR MUCH OF THE SIERRA. THERE IS ENOUGH CONFIDENCE IN WIDESPREAD FORCING AS THE JET MOVES ONSHORE AND UPPER DIVERGENCE IN NE QUAD OF SYSTEM TO ALLOW QPF IN THE SIERRA TO EXCEED AN INCH. ONE LIMITING FACTOR FOR THIS STORM WILL BE RELATIVELY HIGH SNOW LEVELS AS 700 MB TEMPS JUMP UP TO -1 TO -3C IN THE WARM MOIST SECTOR FRIDAY AFTERNOON INTO EVENING. THIS WILL KEEP SNOW LEVELS ABOVE 7000-7500 FEET AS THE HEAVIEST PRECIP STARTS PUSHING THROUGH…LEADING TO LOW SNOW TO WATER RATIOS (A SIERRA CEMENT SCENARIO). SNOW LEVELS TO LOWER LATE FRIDAY NIGHT AS THE COLD FRONT WITH 700 MB TEMPS DROP TO BELOW -8C. SNOW AMOUNTS OF OVER A FOOT EXPECTED IN TAHOE BASIN ABOVE 7000 FEET WITH CLOSER TO TWO FEET SOUTH TOWARD MONO COUNTY DUE TO BETTER FORCING AND OROGRAPHICS. ACCUMULATING SNOWS ARE LIKELY IN SIERRA VALLEYS…BUT WITH THE INITIALLY HIGH SNOW LEVELS…AMOUNTS WILL BE LIMITED TO BELOW WARNING CRITERIA. NORTH OF TAHOE…WEAKER FORCING AND HIGH SNOW LEVELS WILL LIMIT SNOW POTENTIAL AND HAVE LEFT THEM OUT OF THE WINTER STORM WATCH.
SNOW LEVELS SHOULD BE DOWN TO MOST VALLEY FLOORS BY SATURDAY MORNING BUT PRECIP WILL BE WINDING DOWN. THEREFORE…DONT FORESEE MORE THAN A COUPLE INCHES OF SNOW AT BEST TO ACCUMULATE AND MAINLY IN ELEVATIONS ABOVE 5000 FEET IN THE LEE OF THE SIERRA. SNOW SHOWERS TO BECOME SCATTERED BY SATURDAY AFTERNOON WITH A COOL DAY IN STORE UNDER THE UPPER COLD POOL.
Topics: Tahoe Snow Report |
February 25th, 2010 at 10:37 am
RIP CR damn it.
Squaw is having a tought couple years.
February 25th, 2010 at 10:45 am
Yes, RIP CR, extraordinarily influential skier and motivated individual. Another staggering loss for Truckee, Squaw, and the ski-world at large. Hard to know what to say given all the loss over the past few years here, especially losing such amazing people … my family sends its thoughts out to CR and his family. And to all those who skied with him and were inspired by him …