The major storm last week delivered impressive snow totals but also a host of other complications. Roads were closed and lockdowns were in place in Val Thorens, as well as Tignes and Val d'Isère, due to the risk of avalanches. Sadly, an avalanche crossed the access road in Val Thorens, resulting in one death. Power was lost in Chamonix and Zermatt, which became completely cut off for several days. Back-up power was provided to a limited number of areas, but the situation was challenging for many days. The storm caused most resorts with the big snow totals to remain closed on Thursday. 

As far as the snow goes, the totals were huge! Over three meters fell on the Simplon Pass in Switzerland. A wide stretch of 1 to 2 meters fell from the northeastern French Alps in the Savoie region to the Valla d'Aosta region in Italy and the Valais region in Switzerland. While these snow totals are impressive, big April snowstorms in the Alps at upper elevations are not uncommon. It was the snow at lower elevations that was both unexpected and, at times, record-breaking. 

These totals were unexpected given the temperature and snow level forecasts. The snow levels were expected to start around 2,400 m and fall to around 1,400 to 1,700 m. It is important to note the difference between freezing levels and snow levels. The freezing level is the elevation where the temperature is 0 degrees. The snow level is typically below the freezing level, thanks to evaporational cooling. Evaporational cooling occurs when snow falls into temperatures above freezing, and the energy used to melt the snow results in a decrease in air temperature. This allows snow to fall below the freezing level. Snow levels are typically 150 to 500 m below the freezing level.

This storm was unique in that the snow level fell to around 1800 m below the freezing level. The temperature profile was isothermal between 400/500 m and 2200/2300 m, meaning it was 0 degrees across that entire elevation range for much of the storm. This resulted from the intense precipitation and minimal winds. Snow levels dropped as low as 400 m in some locations, and were responsible for the record-breaking snow at these low elevations. Up to 60 cm fell at 1000 m and up to 30 cm at 500 m. 

I chased this storm from Utah to the Alps, in search of some deep powder. Initially, I planned to ride in Verbier on Thursday, but on Wednesday, they announced much of the mountain would stay closed. I pivoted and headed to Val Thorens, given that their lifts remain open during big storms as long as the winds aren't too strong. The enormous snow totals that fell in 24 to 36 hours were too much for the resorts, though, and Val Thorens, along with most others in the region, remains closed on Thursday. Police were driving around Val Thorens, telling everyone to go inside as a home confinement order was in place. The police were walking around town with avalanche airbag backpacks. 

For the most part, the snow tapered off in the afternoon, and the sun even came out at times. This is bad for the snow staying good, though, with the strong April sun wreaking havoc. I saw the sun in Val Thorens and watched the webcams in Val d'Isere, where light snow continued and the skies stayed cloudy. Once the road to Val Thorens opened, I headed down to the valley to ride in Val d'Isere on Friday. The sun was out early on Friday, though, with hardly any clouds, and the snow was affected. Still, north-facing aspects had some decent snow, and soft, powdery turns were available, although it didn't ride that deep. 

I took Saturday off as the snow quality would only deteriorate from there, and waited for another less intense round of snow on Saturday night through Sunday morning. The Valle d'Aosta area received another 20 cm of snow, and Monterosa was empty. I spent the afternoon farming some dense powder under partly sunny skies. 

Some rain and snow showers will linger in the region on Monday and Tuesday, but for the most part, it will be dry. Another storm is expected Wednesday night through Saturday, with more accumulating snow. This storm looks fairly warm, with snow levels around 1800 m, and with northerly winds, will favor the northern side of the Alps. Below is an early look at snow totals.

The glaciers in Austria and the northern Alps from northern France through Austria should do best. Once again, some decent powder turns will be possible on Thursday. 

More rain and snow are possible next weekend, as the latest storm moves south of the Alps and becomes cut off from the flow for a time. This would shift the emphasis back to the southern Alps, but its a bit too early for details. 

My next post will be on Wednesday or Thursday.

Thanks for reading the Europe Daily Snow!

Luke Stone
Forecaster, OpenSnow

Alps Regions:

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