Chase Powder Daily Snow
By Powderchaser Steve, Forecaster Posted 3 months ago November 30, 2023
The incoming series of moisture is still on track with significant totals for the PNW (4-6 inches of water). Decaying pieces of energy from an Atmospheric River will impact the Rockies late Friday to Monday coming in sections, each a bit warmer than the last. I have downtrended the totals slightly.
My detailed forecast was posted on Wednesday pinpointing timing, cold to warm air, Snow/Rain, and totals. I am going to pinpoint some highlights of this storm to add to yesterday's more in-depth post (Read both).
* The highest snow totals will likely fall in the Cascades (20-30 inches) with snow levels starting at 2K Friday.
* Snow levels in the PNW rise to above 5- 6000 feet on Sunday. The highest snow totals appear to be from Stevens Pass to most of the Oregon resorts. Northern areas of Washington near Mt Baker will see a bit less (10-18 versus 20-30). Whistler is in the 6-11 inch range. Significant snow will fall before the rain changeover Sunday so many resorts will be opening soon (Game-changing storm). We needed this storm!
Below U. U of snow totals for Crystal Mountain showing decent confidence in 20 plus inches. The highest lines are at 30 inches, however, these ensembles tend to be a bit overdone. Peak snowfall will be from Friday night to Saturday before the significant warming.
Below: Snow ratios (How much snow per 1 inch of water) plunge from 15:1 initially (15 inches per 1 inch of H2O) to below 5:1 and even 0 by Sunday (Rain). Get it on Saturday!
* The Rockies score 3 pieces of energy (Late Friday/Saturday and again Sunday/Monday) Each wave will come in a bit warmer (Snow ratios start at 18:1 and end near 10:1 Sunday above 8,000). I don't expect any rain with this even aside from the metro valleys near Salt Lake on Sunday afternoon. This will be a decent event with no single 12-hour double-digit. The sum totals will be good. There is still some model downside possible for the Cottonwoods (Close call between the deepest amounts north or south of I-80).
For the Rockies, the highlighted areas for the most snow still focus on western Idaho including the McCall mountains and the panhandle along I-90 and south. Areas north towards Schweitzer will see slightly lower totals including interior BC (Next week looks more active for interior BC). Expect 9-15 inches in some spots by Sunday. Whitefish in northern Montana will grab moderate snow.
The models are pretty consistent in the Tetons with several periods of 3-6 inches every 12-18 hours from Friday PM to Monday morning. Slightly higher amounts are possible Sunday/Monday with warming temps (Storm total of 12-20 inches). The deepest day might be Monday morning as Avy conditions rise (Upside D)
The Wasatch still has some questions on who will see the most snow. There has been consistent model consensus that the northern ranges near Ogden or even Logan might see higher amounts than the Cottonwoods. Snow will increase Friday mid-morning and peak Saturday and Sunday. This storm will start with dry low-density snow and end with medium to dense snow by Sunday afternoon.
Totals are likely going to be 20-25 inches in the northern Wasatch Range (Snowbasin, Powder, Beaver wildcard) with similar totals further south towards the Cottonwoods. The northern Wasatch might outperform. the Cottonwoods, especially Friday to Saturday. There is still model disagreement so some downside is possible especially south of I-80. Total water is still 2-2.5 inches (Highest totals north of I-80).
Park City in the Wasatch Back will likely see 10-18 by Monday. With warming temps Sunday and WNW flow Sunday- Monday the southern Wasatch with higher elevations in the Cottonwoods may be favored.
For Colorado, a weak system tapping some colder air will bring scattered moisture to the southern and central mountains from Thursday to Friday. This system will bring isolated pockets of 3-8 inches favoring the central or southern areas. I am watching Wolf Creek, CB, Aspen, Powderhorn, and Sunlight for a sneak-up powder day on Friday (3-6 or more). Some isolated amounts are likely along the I-70 corridor. The main event for Colorado begins late Friday or early Saturday peaking on Sunday mid-morning to Monday.
The models disagree on how far east the deepest snow will land. I have good confidence on some hefty totals near Steamboat peaking Sunday/Monday and extending south to Aspen, Sunlight, and perhaps Beaver Creek which does well with westerly winds. Moderate confidence exists for areas east towards Vail Pass and Summit County. The best day to ride will likely be Sunday late AM to early Monday.
Below: The American Model is a bit more pessimistic for the Summit County area pushing more moisture north towards Steamboat and south towards the Elk Ranges.
Below: The European Model pushes better totals (Optimist) well into the Vail and Summit County regions by Sunday/Monday (A bit further east). This will also be beneficial for the Divide Resorts however less snow is likely.
I still have no idea where I am chasing yet. Be aware, that the snowpack is still thin in many areas, The PNW is still primarily buttoned up, and with warming temps, any heavier density snow on light density will create Avy concerns. The good news is that after this storm there will be many places to chase powder. Unfortunately, the Sierra is only going to get teased by this storm.
Thanks for following the chase forecast.