Powderchaser Luke here for a special update on the incoming Winter Storm!
It's been incredibly dry in the Southwest the last few months, but that is about to change in a BIG way. There will be a powerful 1-2 punch with this storm, and the mountain will have turned from Fall to Winter in just a few days. By the time the resort opens on Friday, there will be tons of fresh snow from base to summit. For those of you who just want to know snow totals, we're forecasting 16-24\ with the summit possibly approaching 30\". We chased to the Snowbowl three times last year, and we're excited for the resort to get off to a good start.
The lack of rain and snow in the SW has been significant, with severe drought covering most of the Northern part of the state, as seen below.
(image courtesy of Arizona Department of Water Resources)
So, this storm is needed for snow lovers as much as for water resources. While the Snowbowl is getting hammered with snow, much of the Southern part of the state will receive ample rainfall, on the order of 2-3\"+. That's great, but we're here to talk about snow, so let's get to it.
The Storm
As mentioned, this storm will provide a nice 1-2 punch. The first wave will be warm, with snow levels above town and low snow rations (denser snow) to start. This is exactly what we want this time of year, with the dense snow covering up whatever lies on the surface . The second wave will feature a solid cold front that will lower snow levels well below town, and heavy snowfall. in the GIF below you can see the initial wave with high snow levels, with the snow focused on the higher elevations, followed by the second wave with more widespread snow as the snow level falls.
(image courtesy of Weatherbell)
The snow will start falling after midnight, with light accumulations by morning, still during the warm portion of the storm. Some cold air starts to move in around sunrise, with an initial cold front, but the real cold arrives between sunset and midnight. There could be some valley snow before evening if the precipitation is heavy enough, as this can cause the snow level to lower through melting of the snow. By this time, there should be 6-12\" on the mountain. The good news is that the snow will continue to fall, at times heavily, likely through Thursday evening. It won't be dumping the entire time, but you can expect off and on heavy snowfall during this time. By the time opening day rolls around, there should be 16-24\" of snow on the hill. We wouldn't be surprised if the summit eclipses 30\". This will go a long way to building a solid base and providing great opening day conditions. Below is the snow total map from the 3KM NAM model. Maybe a little overdone but this is definitely a solid storm!
(Image courtesy of Weatherbell)
Before moving on to the opening day/weekend forecast, we wanted to share one more graphic that we use to help forecast snow totals. Below are the SREF Downscaled Ensemble Plumes for the Snowbowl, at ~11k. WHAT? Let us explain. First, there are some weather models that can (hopefully) more accurately predict the weather by using a smaller grid size. They typically operate only in the short range <60 hours. The SREF incorporates a few of these high resolution short range models. Secondly, models typically take a bunch of initial data, like temperature, humidity, winds, etc, plug it into some complex atmospheric physics equations, and produce a single forecast. This is referred to as a deterministic model. The SREF involves an ensembles, which instead takes those initial conditions, alters them slightly, and re runs the model. Different ensemble models will re run the model with 10-20 different sets of initial conditions, with the goal of understanding the uncertainty in the forecast. So that is how ensembles work. Onto the image below. All of the lines are the individual snow forecasts from runs with different initial conditions. Snow totals are on the left with time on the bottom. This particular product involves two model's ensembles with a total of 26 different model runs. You can see a wide range of snow totals from as low as 18\" to as much as 60\"! That is a huge range and is evidence of some uncertainty with this storm. There is a general clustering of plumes between 20-40\" though, which helps us get a general idea of what type of totals can be expected.
(Image courtesy of the University of Utah)
Opening Day Forecast
Lastly, we'll discuss the conditions for opening day and opening weekend. On Friday, the heaviest snow will have ended, but there could be some snow showers lingering in the AM. By the time lifts open, things should be starting to clear, with partly sunny skies and chilly temps, mid 20s at the base low 20s up top. It is shaping up to be an incredible opening day.
Weekend Forecast
Opening weekend looks stellar as well. Temps will again begin to warm on Saturday and continue to do so for Sunday. Expect the high to be in the mid to upper 30s at the base on Saturday, and upper 20s at the summit. Sunday will be even warmer, with a high in the upper 30s at the base and upper 20s again at the summit. Expect partly sunny skies on Saturday and mostly sunny skies on Sunday. Not a bad way to kick off the season!
We will close out this post with an image from one of our chases to the Snowbowl last season. There IS a snowboarder in there!
(photo by Joshua Esquivel)
PLEASE CONSIDER USING OUR CONCIERGE CUSTOM FORECASTING FOR THE UPCOMING SEASON: https://powderchasers.com/concierge
Powderchaser Luke