Weekend Forecast, 1/21/2016 – 1/22/2017:
From Dan Tackett, Sugar Bowl National Ski Patrol Meteorologist Extraordinaire
Updated Thursday, January 19th, 9:00 pm
The dry weather last weekend allowed the chance for a major dig-out after the previous week of exceptional storms. A weak high pressure ridge was responsible for the respite, but it quickly began to drift eastward on Tuesday as another storm cycle loomed offshore. A brief shot of snow began the wet pattern just before sunrise Wednesday, then accumulations became heavy just before noon. Last week, the models had the initial surge of moisture coming in as rain, but a low pressure trough offshore drifted far enough south to push cool air into the system. Unlike earlier extended events this month, no day of rain will interrupt the snow. Accumulations through the afternoon and overnight added up to 12-20 inches.
Although the brunt of the storm was well to the east on Thursday, a cool, unstable flow off the Pacific kept snow showers going all day. An additional 6-12 inches fell with a few more inches expected overnight. In January 2015, just 2 brief years ago, virtually no accumulations occurred for the entire month. It seemed impossible to get any snow going in the Northern Sierra. A 6 inch snow event became something to celebrate. Currently, a couple of people simultaneously hiccup and another foot of snow falls. This month, snow has been easy.
The second system in the current storm cycle will get the snow going again pre-dawn Friday. Snow will be steady into the afternoon, then slowly reduce to snow showers in the late afternoon and evening. An additional 12-18 inches of accumulations are expected by the evening. Temperatures will be cool, in the low to mid 20s, allowing the snow to be less dense than some of our earlier events. Southwest winds will be moderately gusty, almost tame compared to some of the winds we’ve seen this month.
Although Saturday will be the quiet day of the weekend, snow and snow showers will continue in the lull between storms. Accumulations through the day are “only” expected in the 3-6 inch range. Temperatures continue on the chilly side with lows in the upper teens to low 20s, with the high temperatures barely climbing into the low to mid 20s. Southwest winds not bad in the morning will perk up in the afternoon as yet another storm begins to approach.
The third and most potent storm in the cycle quickly approaches late Saturday night and revs up the snow before dawn on Sunday. Snow, heavy at times, will accumulate through the day and overnight. Along with gusty southwest winds, definitely a full on storm day. Accumulations pre-dawn through sunset are in the 12-16 inch range, with another round of 12-16 inches expected overnight. Temperatures will be relatively steady in the low to mid 20s.
Snow showers continue on Monday as a low pressure trough treks across Northern California. Accumulations by the evening may reach another 5-10 inches. A high pressure ridge will begin to divert the storm track well to the north on Tuesday. A few snow showers or flurries may still hang around in the morning, but a drying trend will be underway. With this version of the high pressure ridge appearing to be the strongest of the month, quiet weather is likely for the rest of the week. With so much ground moisture in place, inversions of cool air in the valleys may produce low clouds, while the slopes bask in sunshine.
Sugar Bowl Snow Depths as of Thursday, January 19th:
Station A near the base: 86 inches. Last year at this time: 62 inches
Station B mid-mountain: 136 inches. Last year at this time: 110 inches.
Current Truckee River Drainage Snowpack Water Equivalent to Normal: 187%
Weekend forecast for 1/21/2017-1/22/2017:
Mostly cloudy on Saturday with snow and snow showers through the day. Daytime accumulations in the 3-6 inch range. Lows in the upper teens to low 20s, highs in the low to mid 20s. Southwest ridge winds to 30 mph with higher gusts, light elsewhere, increasing in the afternoon.
Snow, heavy at times, on Sunday. Accumulations through sunset in the 12-16 inch range. Temperatures steady in the low to mid 20s. Southwest winds to 15 mph with higher gusts, to 60 mph on the ridges with higher gusts.
Weekend Travel Weather:
Challenging road conditions Friday through Monday, with chain restrictions likely during the entire period. Possible closures on I-80 Sunday and Sunday night.
Moderate accumulations on Monday, transitioning to a dry pattern sometime on Tuesday.
Have a Great Weekend.