There is some significant snowfall coming down in the Alps at the moment, during a period of really lovely, steady snowfall in the past few weeks.
This is good enough to allow some resorts to open early, with Tignes reknowned for its long season by French standards - opening a week earlier than scheduled. Furthermore, this isn't skiing on a ribbon of white surrounded by green valleys; there is really good snow coverage at all elevations and across all aspects, creating a good snowpack to build on for the rest of the winter.
It's not all good news though. Remember last year? A good start to the season was washed away by warm weather and rain around Christmas, so we're not out of the woods yet. And away from the Alps, temperatures have been more inconsistent, already creating weak layers in the snowpack that could play havoc for weeks or even months to come.
In this blog I talk more broadly on early season snowfall - how it can be good, how it can be bad, and how it can still be downright ugly.
The Good: November Powder Turns
One of my favourite resources to use for snow forecasting is somewhere called WePowder. They are a Dutch website that provides really in depth forecasting for the whole of the Alps, using maps to clearly demonstrate where the snow is going to fall.
Alongside this, they also feature blogs and, important for powder chases, powder alerts, of which the first one of this season was issued this week. These powder alerts are short term forecasts that indicate big dumps are on the way, telling you where and how much snow to expect.
WePowder have forecast over a metre of snow in some parts of the Alps to fall in the next six days, especially on the northern edges of the Swiss and Austrian Alps - places like Engelberg, St Anton and Wengen will be hit hard.
This means it will be possible to score some serious powder turns in the coming days, very rare for this early in the season. Both the volume of snow and, critically, the stable snowpack it is lying on, provide the perfect platform for punctual powder perfection.
The Bad: Early Season Weak Layers
Early season snow has the potential to have a long lasting impact on a resort's skiing season. If the wrong conditions prevail between one snowfall and the next, the creation of a persistent weak layer is highly likely and all of a sudden the avalanche forecast goes through the roof.
A weak layer is a band of snow that has failed to bind effectively with the layers above and below it. Early in the season, it tends to stem from snow thawing as the temperature rises in mild autumnal weather and then freezing again, either overnight or as the temperatures drop heading into winter. This increases the quantity of water per volume of snow, and creates a solid layer of snow; snow that falls after this will likely sit on top of this solid layer rather than bind to it. The solid layer then acts like a slide, allowing snow to move quickly over the top of it, creating an avalanche if energy is allowed to propagate through this layer.
Currently, temperatrues have remained cool enough in the Alps that this weak layer has not been created; new snow is binding succesfully to the old snow below, and predicted volume of snow in the coming days can be expected to do the same, rather than building up the potential scale of an avalanche.
Across the pond, however, things aren't so good. The Utah Avalanche Centre is reporting the creation of a weak layer across all their forecasting areas that is really particualrly unstable, not even holding long enough for them to conduct stability tests. If not dealt with, these weak layers will become a problem for weeks and months to coming.
It's not necessarily the end of the world; skiers and snowboarders only impact snow about a metre down into the snowpack, so eventually these layers will be buried deep enough that the risk they pose will be limited. However, they can reveal themselves again in the spring as the snow melts and until they are buried, they pose a significant avalanche risk in the interim.
This excellent short video from the Utah Avalanche Center highlights the incredibly weak nature of their current snowpack (22 November 2023)
The Ugly: A Wet Christmas
The Alps are some of the unpredicatble skiing mountains anywhere in the world, especially in France. Unlike many other places, which are cold enough and wet enough that snow is almost guaranteed to happen, the Alps are reliant on particular weather patterns for their snow.
This is particularly true with those areas to the south, as warm air from the mediterranean can very easily damage and destroy a snowpack almost overnight. This is exactly what happened last year, when warm weather and torrential rain wiped out the early season snowpack virtually overnight right before Christmas 2022.
The current snowfall is good - really good. It should survive intact until the New Year when more guaranteed cold temperatures come in, and the gossip around the water cooler is that this particular El Nino cycle will maintain these cold and snowy conditions for some time to come.
We're not out of the woods yet. Keep your fingers crossed and light a candle to Ullr (Norse God of snow and skiing) that this fine start to 2023/24 continues.
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