Thursday, January 9, 2014
We are currently in a lull between the departing weak wave last night and the far more impressive wave timed for tonight. Snowfall will be increasing again this afternoon, especially after sunset as the cool air begins moving over the area. Accompanied with moderately strong northwest flow, I would expect 6-12” by Friday morning, with optimistically some Steamboat magic occurring between 5am and 9am. Snow will lighten later in the morning before picking up again later in the afternoon as a trailing wave moves just northeast of the area.
Models have trended further northeast with this trailing wave, reducing expected snowfall late Friday into Saturday and increasing the chance that high winds will impact the ski area. Snow will become lighter by midnight as the air mass warms and stabilizes, and the snow will likely stop for a short time Saturday, though troublesome winds will continue. I might expect another 5-10” by Saturday morning with only a small amount of that occurring after midnight Friday.
The final wave affecting our area by Saturday afternoon is also cool, moist, energetic and from the northwest. Cooling temperatures will help reduce winds later in the day, and I would expect another 6-12” by Sunday morning, again optimistically with some Steamboat magic occurring between 5am and 9am. The morning snows should lighten during the day, but will likely persist through Monday afternoon. Most of the forecast 3-6” of snow by Monday morning will have fallen Sunday.
A dry and grazing wave in northwest flow looks to bring more cool air into the area Monday night, but no precipitation is currently expected. Likely a couple of brilliant sunny days Tuesday and Wednesday as mountain slopes warm, though valley inversion will reform and strengthen. Another grazing wave in northwest flow may bring some cool air into the region around Thursday, though models are currently struggling with the westward extent of this wave.
Big model differences emerge for the next weekend as the American model breaks the west coast ridge down and allows substantial energy and moisture into the central west coast where they desperately need it, while the European model hints that the ridge will dominate.
Wednesday, January 8, 2014
3” of new snow was reported at mid-mountain at 1pm with temperatures in the upper 20’s, while the upper mountain had a temperature around 10F. I feared dust-on-crust conditions up top, but was very pleasantly surprised to find very soft skiing everywhere.
The snow that fell was comprised of very small rimed snow crystals that formed a dense but buoyant surface. Riming occurs when snow crystals fall through a moist cloud layer comprised of supercooled water droplets. These water droplets then freeze on the snow crystal and obscure its original pristine shape. In fact, when the original shape of the crystal is no longer identifiable, the precipitation is referred to as graupel.
My perfunctory first run down Shadows found soft snow and big patches of the 3” of unskied powder. Next over to the Twilight area, of which the first half pretty much skied the same as Shadows. The lower half was warmer and more tilted to whatever sun we had up there this afternoon, and was getting heavy.
Last run I ripped down Sundown lifline, and the tracked up snow skied soft and bouncy and was extremely carveable. Then, up Elkhead to first catch Concentration, and then the last ride up Thunderhead for Vertigo. Both of these runs also skied soft and bouncy, very similar to Sundown liftline. A quick ride up Bashor lift to access See Me, which also skied great, to end the afternoon.
After about 2” of snow last night, another weak wave traverses the area tonight. There is not much cool air associated with this wave, so I would expect another several inches by Thursday morning after light snow begins this afternoon.
Snow may let up a bit Thursday, but likely not end high on the hill. The next wave affects our area by Thursday afternoon. Yesterday, I was concerned about this wave splitting as it moved over the Great Basin, but the European model solution has uncharacteristically moved toward the American model solution and now keeps the wave far more intact. Confidence increases, then, that significant snows will occur Thursday night when the main wave passes and again Friday night as a trailing wave sneaks through behind the departing main wave.
Snow will wane early Thursday before increasing again, especially after sunset as the cool air begins moving over the area. With cool air and a moderately strong and moist wave in stiff northwest flow, I would expect 6-12” by Friday morning, with optimistically some Steamboat magic occurring between 5am and 9am. Snow will lighten later in the morning before picking up again later in the afternoon and likely becoming heavy as the trailing wave moves over the area.
Snow will become lighter by midnight as the air mass warms and stabilizes, and the snow will likely stop for a short time Saturday. I might expect another 6-12” by Saturday morning with only a small amount of that occuring after midnight Friday.
The final wave affecting our area by Saturday afternoon is also cool, moist, energetic and from the northwest, so I would expect another 6-12” by Sunday morning, again optimistically with some Steamboat magic occurring between 5am and 9am. The morning snows should lighten during the day, but will likely persist through Monday morning. Most of the forecast 3-6” of snow by Monday morning will have fallen Sunday.
A dry and grazing wave in northwest flow looks to bring more cool air into the area Monday night, but no precipitation is currently expected. Likely a couple of brilliant sunny days Tuesday and Wednesday as mountain slopes warm, though valley inversion will reform and strengthen. Another grazing wave in northwest flow may bring some cool air into the region around Friday, though models are currently struggling with the westward extent of this wave.
Tuesday, January 7, 2014
At least 4 distinct waves will influence our weather starting tonight, with snow in the forecast through next Monday. Light snow should start later today as the first weak wave moves over us tonight. Accumulations will wait until cool air enters the area by midnight. Even though the wave is weak, flow is from the northwest so I would expect several inches of snow in the Wednesday morning report.
There may be very little break between waves Wednesday morning before the next wave passes mostly south of the area by late Wednesday afternoon. Again, several inches of accumulation are expected by Thursday morning as we are in favorable moist northwest flow, though cooling is limited.
Perhaps another small break Thursday morning before the next stronger, but splitting wave approaches the area. This is the storm models have been struggling with these past few days. Initially, the European model had the wave cut off from the main jet and staying south of use (a cutoff low), while the American model kept the wave coherent and progressive. As is sometimes the case when model disagree, current model solutions area average the two earlier disparate solutions, with a splitting wave staying mostly coherent and progressive. As a result, snow should begin again later Thursday afternoon and continue into Friday evening. Amounts will be dependent on how much energy is left in the northern half of the split, but amounts currently look in the 3-6” range.
Even though we will be in-between systems early in the weekend, moist northwest flow in a warming and stabilizing airmass will keep clouds and perhaps some very light snow showers going Saturday morning. The fourth wave will be the strongest and coldest of this series, and will affect our area beginning Saturday afternoon. Snowfall looks to peak early Sunday morning and then again Sunday evening as a trailing wave crosses the area. All told, I might expect 6-12” when the Sunday and Monday morning reports are added.
Current long term forecasts have the snow ending after this final wave as a ridge builds over the area. However, there are some indications that the Hudson Bay polar vortex may again expand westward into this building ridge, leading us susceptible to cold air outbreaks by the end of the workweek.
Sunday, January 5, 2014
Currently it is -6F up top with 20 mph winds gusting to 30mph. Very light snow should continue on the hill through this evening as the last arctic surge moves through later this afternoon leading to additional accumulations of several inches by the Monday morning report. Valleys should see some periods of sun.
Ironically, the cold front has warmed the valleys by mixing out the very cold air, but inversions will reform beginning tonight leading to very cold temperatures. Mountain slopes, though, will begin warming tomorrow as we see sun and then warm further on Tuesday as the air arctic air mass moves east.
A couple of weak and disorganized Pacific waves move across the area or just south of the area late Tuesday. Snow may begin late Tuesday or Wednesday and continue until late Wednesday night. The leading wave, though weak, will contain some moisture and will turn the winds to the northwest, so I might expect 3-6” from Tuesday night through Thursday morning.
Perhaps a short break on Thursday before the next stronger wave approaches our area. The American model insists the wave will be progressive which leads to a good shot of snow for Friday, but the European model has this wave splitting as it enters the coast, minimizing or eliminating precipitation for our area.
In either case, both models have another wave timed for late in the weekend which should produce some snow for our area.