Weekend Forecast for 12/7/2013 – 12/8/2013:
From Dan Tackett, Sugar Bowl National Ski Patrol Meteorologist Extraordinaire
Updated Thursday, December 5th, 2:30 pm.
With the opening of Sugar Bowl confirmed, it’s again time to check out weekend weather at the resort. It’s been a slow start this season, hopefully meteorological conditions will improve through December.
The Thanksgiving holiday weekend proved to be dry and very mild, conditions better for pleasant hikes than skiing. The first West Coast artic air mass of the season began to push south of the Canadian border on Monday. Moisture ahead of the cold front brought light accumulations before dawn on Tuesday, followed by the cold air finally arriving shortly thereafter to bring more accumulations and a proper winter chill. Sunrise temperature at the base was at 30 degrees, falling to 14 degrees at sunset and then down to 7 degrees at sunrise Wednesday. Moisture was limited due to the inland track of the cold front, but several inches were squeezed out by the cold air arrival on Tuesday.
Sunny skies and a cold air mass greeted Wednesday and Thursday. Temperatures during the day reached the teens to low 20s, recovering from the single digits of the early morning. An approaching area of low pressure on Friday will increase the clouds and bring the promise of accumulations.
Temperatures will remain cold on Friday despite the increase in clouds. This system will be dropping down from the north, but unlike last Tuesday’s system, this one will tap into some Pacific moisture. It won’t be a great amount of moisture, but the cold air mass will be very efficient at producing snow. Snow ratios Friday night are expected to be 20:1, helping to bolster accumulations. A system riding off the Pacific without help of a cold air mass will produce a snow ratio of 10:1, where an inch of liquid precipitation equals 10 inches of snow. The cold nature of the upcoming system will double the accumulations out of the same amount of liquid precipitation. I call this increase of accumulations as the fluff factor. Yes, the upcoming storm will be a powder producer.
Snow chances begin Friday afternoon with little or no accumulations expected by sunset. The accumulations will primarily occur overnight and into Saturday morning. Accumulations by noon on Saturday are in the 15-22 inch range. Southwest winds pick up on Friday afternoon, but this system is not a major wind producer.
Snow and snow showers on Saturday morning then decreasing in the afternoon. Temperatures will be steady in the teens. Moderate morning westerly winds will decrease in the afternoon. No accumulations are expected after sunset.
Clearing on Sunday as the system moves into Southern California and weakens. Temperatures will remain quite chilly with lows near 0 to 10 degrees and highs in the teens to low 20s. A moderate easterly wind will create a very brisk chill factor, at times below zero. Definitely break out the full-on winter gear this weekend.
A westerly flow off the Pacific on Monday is expected to begin pushing the cold air mass off to the east. Temperatures will moderate each day with daytime temperatures well into the 30s by Wednesday. The storm track will be extended well to the north, keeping the Northern Sierra dry Monday through Wednesday. Snow chances finally work their way closer on Thursday.
Sugar Bowl Snow Depths as of Thursday morning, December 5th:
Station A (near the base of Crow’s Nest Chair): A few inches. Last year at this time: 11 inches.
Station B (between Calif St & Station B runs): A few inches. Last year at this time: 59 inches.
Current Truckee River Drainage Snowpack Water Equivalent: 55%
Weekend forecast for 12/7/2013-12/8/2013:
Snow and snow showers Saturday morning, decreasing in the afternoon. Accumulations overnight through noon ranging from 15-22 inches. Temperatures steady in the teens. Westerly winds to 20 mph with higher gusts, to 35 mph on the ridges with higher gusts, decreasing in the afternoon.
Clearing on Sunday. Lows near 0 to 10, highs in the teens to low 20s. Easterly winds to 20 mph with higher gusts, to 40 mph on the ridges with higher gusts.
Weekend Travel Weather:
The earlier up the mountain on Friday, the less chance of travel difficulties. After sunset, the snows may start to accumulate at any time. Winter road conditions on Saturday morning with chain controls likely to begin in the foothills. The fluffy nature of the snow is easier to blow around, thus reducing visibilities. Conditions improve Saturday afternoon. Caltrans will probably be finishing up Sunday morning with much better road conditions for the afternoon ride down the mountain. Slippery spots will remain.
Dry through mid-week, hopefully snow chances improve later in the week.
Have a Great Weekend and a Great Season,