The Alps Snow Thread - Season 2014/2015

[J10]

Truly wonderful day in the French Alps. Clear blue skies and fantastic skiing to be enjoyed. Pistes are perfect at height but warming up down in the village reaching 12C this afternoon so the lower slopes turned into a mass of slush!

 

Some photos of the 'bowl' up at 2,000 to 2,800m. 20150318_094946.jpg 20150318_095005.jpg

 

Oh, and my lunch 20150318_133141.jpg

 

Lovely photos there of both lunch and the slopes, looks lovely.

[carinthian]

Hi all,

Still plenty of good snow conditions to be found in the high tauern mountains. This picture taken 5 days ago.

C

[carinthian]

I cant believe its 50 years ago this week that the Beatles filmed here in Obertauren for the film Help. Great celebration week here in Obertauren with lots of Beatles music and tribute bands this weekend. Fans from all over the world in the village.

[J10]

https://forum.netweather.tv/blog/189/entry-4879-alps-weather-forecast-20-march-2015/

 

Latest Blog out and another mixed week in the Alps, very much in the mix between winter and spring.

[J10]

I didn't do the weekly snow round up this week. (From Snow forecast) but I just noticed this little titbit.

 

FRANCE Fantastically sunny weather blessed the resorts on Thursday 19th March. Overall spring-like skiing was enjoyed although the higher resorts like Tignes (100/160cm), Val d'Isere (100/160cm) and Val Thorens (115/200cm) had some of the best conditions if you like snow that does not soften as quickly through the day. The Haute Maurienne Vanoise resorts of Bonneval sur Arc (90/180cm) and Val Cenis (60/310cm) are also skiing very well due the good amount of fresh snow they have received recently. Bonneval had 25cm of new snow land on 16th March while Val Cenis reported 15cm on the same day. Cloudy weather is expected to move in over the resorts as we head into the weekend, and fresh snow is forecast at all of our featured resorts. The heaviest snowfall should land at La Grave (30/160cm) which could receive around 40cm of fresh snow over the weekend and almost 80cm by the end of next week. The Chamonix valley (0/180cm) could also see a good amount of new snow arrive over the same period, along with the Haute Maurienne Vanoise area and the Espace Killy. Flaine (37/185cm) and Les Deux Alpes (60/210cm) could receive 40-50cm of new snow by Friday 27th March too.

Edited March 22, 2015 by J10

[Blessed Weather]

I didn't do the weekly snow round up this week. (From Snow forecast) but I just noticed this little titbit.

 

FRANCE Fantastically sunny weather blessed the resorts on Thursday 19th March...... The Haute Maurienne Vanoise resorts of Bonneval sur Arc (90/180cm) and Val Cenis (60/310cm) are also skiing very well due the good amount of fresh snow they have received recently. Bonneval had 25cm of new snow land on 16th March while Val Cenis reported 15cm on the same day.....

 

Ah! Good stuff Julian. This year was my 14th visit to Val Cenis and it's nice to see this relatively unknown resort getting a mention (although in the last few years a couple of the big ski companies have discovered the resort, so this is changing). And by the way, sunny weather blessed Val Cenis on Wed, Thurs and Fri!

 

The snow depths that resorts quote is an interesting topic. It's well known that resorts are, shall we say, somewhat generous with their figures. But to be fair to the resorts, my recent trip highlighted the different depths that can fall on the various slopes, depending on factors such as wind direction and local topography. Val Cenis is right on the border with Italy and usually gets its heaviest snow from fronts moving up from the S or SE. The locals call the wind from Italy the "Lombard" for obvious reasons. It can result in more snow falling on certain slopes than on other more sheltered slopes. Here's a couple of photos to illustrate the situation in Val Cenis. The first is taken at the top of the highest lift and looks down over the frozen (lake) Lac du Mont Cenis. Beyond the lake is the Italian border and the valley you can see on the left of the photo descends all the way down into lowland Italy so that the wind literally climbs all the way up the valley until in my second photo it "pours" over the col between two peaks rather like a fog.

 

The view towards Italy The Lombard wind pouring into Val Cenis

 

So last week, with low pressure over Italy, Val Cenis did well for snow but the slopes below where the Lombard flowed through the col did best (I estimated around 30cm on certain slopes and only a few cm in the village). As your weekly blog suggested, there's yet another low set to develop over Italy later this week. And once again, whilst precipitation doesn't progress very far over the Italian/France border, Val Cenis should benefit, as the Euro4 chart for this Weds shows:

 

 

By the way, Bonneval is an amazing little village at the end of the valley, a few miles beyond Val Cenis. It's got amazing off-piste but you need a guide to safely enjoy it. In the summer there's a small and rather scary road that goes up (and up) and then drops down into Val d'Isere.

[J10]

Thanks again for you kind words, and sensational photos.

 

One question in terms of snow forecast do the automated forecasts tend to overstate potential snow amounts, as form my thinking this is a bit of an issue.

[johnholmes]

I think that is iften the case Julian. Trying to predict snowfall amounts is fraught anyway. Even local forecasters in Switzerland come a cropper at times and quite close to T00 as well. The clever bit would be knowing when to believe a model and when to think it is wrong. I ain't good enough to do that!

[J10]

I think that is iften the case Julian. Trying to predict snowfall amounts is fraught anyway. Even local forecasters in Switzerland come a cropper at times and quite close to T00 as well. The clever bit would be knowing when to believe a model and when to think it is wrong. I ain't good enough to do that!

 

What chance the rest of us then !!!!

[Blessed Weather]

^ It would seem (from my personal observations) that the automated forecasts are more inclined to overstate forecast snowfall amounts than to understate. And in the 5 day run-up to a snow event the forecast amounts can swing up and down on each model run. So as John says, it's a "fraught" business! For my trip to Flaine in January the forecasts varied from around 40cm all the way up to 130cm. In the end I estimated about 80cm fell. For my trip to Val Cenis last week the forecasts suggested far more (and more widely) than actually materialised. 

 

What I would like to understand is what base model output do the various websites/organisations use to generate their automated output?? Do Meteo France use ECM or GFS to derive their forecasts? Are they regurgitating the 'raw' model output or are they applying their own overlay software? Ditto question for snowforecast.com, Osterreich.wetter, Meteo.central Swizterland, Ski Club of GB, etc, etc.

 

My comment in post #431 was about the amount of snowfall a particular resort actually receives when a snow event happens as this is where the "poetic licence" creeps in. The regular reports stating the depth at the base and upper slopes tends to be fairly accurate, at least in France as all the resorts check the table published in Le Dauphin (see here: http://www.ledauphine.com/meteo/meteo-neige ) and questionable figures from a resort are apparently quietly challenged!

 

I found the following report even more interesting than the question of exaggerated snow amounts that may (or may not!) have recently fallen!! Did any of us realise that the official "kilometres of pistes" figures from most resorts is considerably overstated? Here's some extracts from a recent report: 

 

How does one measure a ski slope? To this simple question, stations respond with complicated calculations that allow them to inflate by 34% on average length of their tracks and even, for some, to double, according to a German study.

 

The site of the 3 Vallées, the largest ski area in the world (Savoie) and 493 km of runs 600 km and not displayed, an exaggeration of 22%, according to this study by the German consultant Christoph Schrahe.

 

The Franco-Swiss Portes du Soleil area boasts 650 km of tracks him against 425 km in reality (53%) and the 2 Alpes (Isère) 228 km instead of 134 km (+ 70%).

 

For some stations, the gap is doubled: Les 4 Vallées (Switzerland) with an exaggeration of 151%, Sybelles (Savoy) with 120% or Isola 2000 (Alpes Maritimes) with 123%.

 

To achieve these results, Christoph Schrahe, who is interested in the question for thirty years, has spent "at least 1000 hours" to scan and measure the ski slopes using Google Earth.

 

According to his calculations, the bidding is a widespread practice in Europe. Few stations to publish figures in line with reality.

 

The publication of this study has already led the Austrian Association of lifts to issue a recommendation requiring stations to redo their calculations.

 

In the aftermath, the station Hochzillertal in Tyrol, lowered the length of its tracks 88 km, 181 km against before.

 

The stations interviewed by AFP barely concealed their embarrassment when asked to explain their counting method.

 

Some refuse to answer despite several requests. Others maintain the greatest uncertainty as to the method used.

 

The full report with more detail including likely reasons and resort 'excuses', in French: http://www.ledauphine.com/france-monde/2013/09/20/les-etranges-calculs-des-stations-de-ski-pour-gonfler-la-longueur-de-leurs-pistes

[J10]

Latest Snow blog out now

 

https://forum.netweather.tv/blog/189/entry-4881-alps-weather-forecast-27-march-2015/

 

The rather mixed conditions continue, best in the North East, with the risk of more general cold weather over Easter weekend

[Blessed Weather]

We're now in the run-up to the end of this winter season and for some resorts it's their final week. Resorts closing on the 6th April include St. Moritz, Bad Kleinkirchheim, Grindlewald, and Garmisch.

 

However, there's a great choice of resorts remaining open for a further week (until 12th April) and many of them still have LOTS of snow on their pistes! So there’s still great skiing/boarding to be had. And whilst there will still be a number of higher resorts remaining open after the 12^th, the choice thereafter does become limited.  

 

So for anyone thinking of grabbing a late week's holiday this winter season, here’s some info to help with your decisions.

 

Resort closing dates: http://www.onthesnow.co.uk/europe/projected-closing.html

French resort snow depths: http://www.ledauphine.com/meteo/meteo-neige

Austrian resort snow depths: http://www.wetter.at/wetter/sport-freizeit/ski-wetter/oesterreich

Switzerland resort snow depths: http://www.onthesnow.com/switzerland/skireport.html

Italian resort snow depths: http://www.onthesnow.com/italy/skireport.html

 

And what about the all-important weather? Well, as J10 says in his latest blog (above), there are good indications that the weather might turn colder for the Alps for the Easter weekend, setting up a great final week for many resorts. This evening’s models offer up some interesting charts. Please note these forecasts go beyond the time limits for any real confidence in model accuracy, but nevertheless with the two models suggesting similar set-ups, it gives a flavour of what might happen that week. And over the coming week I’ll revisit the models and give a couple of updates, and of course we’ll look forward to J10’s final weather blog of the season next weekend.

 

GFS Sat 4th April  ECM

 

GFS Mon 6th April  ECM

 

Both models then tentatively suggest high pressure builds in for the second half of the week. What more could you want from spring skiing? Sunny by day, freezing overnight, re-groomed pistes in the morning, and a leisurely lunch in the sun! Go on.... you know you want to!

 

GFS Wed 8th April

[Blessed Weather]

Ever wondered how you would get off a chairlift if it got stuck? Well here's some pictures from Les Orres resort from last Friday 27th March. Easy peasy!!

 

[johnholmes]

mmm-not my idea of fun!

[alr1970]

Go on.... you know you want to!

 

I do...and I am...La Plagne for a week from Saturday, looks very encouraging.

[J10]

Ever wondered how you would get off a chairlift if it got stuck? Well here's some pictures from Les Orres resort from last Friday 27th March. Easy peasy!!

 

Les Orres chairlift rescue 1.jpg Les Orres chairlift rescue 2.jpg Les Orres chairlift rescue 3.jpg Les Orres chairlift rescue 4.jpg

 

I'd end up panicking.

[Blessed Weather]

I do...and I am...La Plagne for a week from Saturday, looks very encouraging.

 

Fantastic! I'm very envious. Skied La Plagne a few years back and thoroughly enjoyed it - some wonderful long runs. Well it's definitely looking very good for you alr1970. A pure co-incidence, but yesterday the local newspaper that serves the French Alps featured La Plagne and the amount of snow expected this week.

 

 

The snow forgets it should be spring skiing. At La Plagne, snow fell on the night of Sunday to Monday 30 cm of snow, and more than 40 inches were expected in the night of Monday to Tuesday. Good news for La Plagne, like other resorts of Haute Tarentaise where it is also snowing.

 

Le Dauphine article in French: http://www.ledauphine.com/actualite/2015/03/30/la-neige-ne-va-pas-manquer-pour-le-ski-de-printemps

 

Looking at the latest forecasts, many resorts in the Alps are set for a good fall of snow this week. Freezing level starts dropping later today and pistes above around 1,500m should really benefit (lower in the NE Alps). Mid-station at Wengen (Switzerland) is forecast 80cm, mid-station at Katschberg (Austria) is forecast 60cm. It's a great set-up for the final 'big' week of the season (4th - 11th April).

 

Euro4 Wed 1st April

 

Edit: The avalanche risk continues to cause great concern. This bulletin from Chamonix yesterday, but really it's an Alps-wide problem:

 

Chamonix: the very unstable snowpack requires great caution. The mayor of Chamonix, the Chamoniarde - prevention society and mountain rescue - and mountain professionals, encourage off-piste skiers, climbers and hikers, whether walking on snowshoes or skis to most alertness. Indeed, significant amounts of snow windy now introducing aloft causing great instability of the snowpack.

Edited March 31, 2015 by Blessed Weather

[carinthian]

Nice overnight snowfall, up to 20cm on higher pistes. Looking good for this long weekend. More snow clearing of the drive looks likely.

[Blessed Weather]

We seem to have mentioned the avalanche risk many times this season. The subject was hitting the headlines again yesterday in the local French Alps newspaper:

 

The season of many traps
Hautes-Alpes, a slope of more than 30 degrees, a snowfall and windy, risk 3, marked and not average, making the difficult decision.....

The scenario of the accident yesterday has an air of déjà vu in this season where there were 34 deaths in our massive avalanches (including 26 just for the southern Alps). Almost half of these deaths occurred in this department.

Like the month of January when the snow cover was not consolidated, with fragile sub-layers due to the (early season) lack of snow, unusual at this stage of the season, early April has not really (shown the) characteristics of a classic spring, with its melting avalanches, caused by daytime heating. "We have an unusual wind with very specific conditions, snow succeeding heat," says Abdou Martin, president of the company of Oisans-Ecrins guides.

Significant falls since last weekend saw the freshly fallen thickness relent, the wind blew again weakening the mantle. "A phenomenon of hard plates which can be explained by large accumulations with stormy episodes, says his aide Christian Trommsdorff, vice president of the union of the guides. The risks are often very localized, and do not (always) match the general level displayed on the scale of the mountain.
 

The 2014/2015 season has been deadly for the Alpine region including Switzerland, a country with a long tradition in the field of prevention of avalanches and lamenting 27 dead so far. Last week at the Pigne d'Arolla, the Chamonix-Zermatt route, a similar accident occurred with an avalanche taking seven German skiers where one died.

 

Article in French: http://www.ledauphine.com/faits-divers/2015/04/01/on-a-un-vent-inhabituel

 

Edit: Update regarding the incident referred to above:

 

The seven survivors of the avalanche that left three dead and one seriously injured yesterday in the Ecrins are interviewed since Thursday morning in the premises of high mountain Gendarmerie. Two men of Austrian nationality and "who present themselves as guides" among the group of skiers swept away in an avalanche Wednesday in the Ecrins (Hautes-Alpes), were taken into custody today (Thursday), according to prosecutors. "There are two people who are as guides. The investigation should verify if these two people could exercise under the Austrian and French law, "said the prosecutor.  http://www.ledauphine.com/hautes-alpes/2015/04/02/les-rescapes-de-l-avalanche-auditionnes-par-les-gendarmes
 

Edited April 2, 2015 by Blessed Weather

[Blessed Weather]

I was going to make this post yesterday (Weds) but the high winds we've been experiencing in Suffolk this week finally brought down a very large willow tree - right onto the electricity transformer serving my area. So no electricity from mid-afternoon until mid-night meant no Internet. So my apologies to J10 that this post is nearer to his weekly blog than I intended.

 

Anyway, it's continuing to look good for those heading off for the final 'major' week of the Alps season, before many resorts then close on the 12th April. The snow that's been falling widely this week will continue on and off right through until next Monday 6th, so pistes above around 1,700m shouldn't be lacking snow! 

 

Sat 4th  Sun 5th  Mon 6th

 

Looking at the precipitation charts above, it makes me wonder how snowforecast.com can arrive at the following forecast for La Plagne, i.e. showing no snow accumulation. Meteo France confirm 80% chance of snow for La Plagne on Saturday with freezing level at 1,400m.

 

snowforecast.com showing no snow accumulation??

 

Thereafter it looks like things dry out and for the French Alps the sun is expected to come out. Austrian & Swiss Alps are looking more likely to keep some snow showers with sunny spells. The more settled weather brings a rise in temperatures during the week as the colder air moves off east, but critically the temps fall below freezing each night, allowing pistes to be groomed ready for great skiing/boarding every morning. At the start of the week afternoon freezing levels around 1,800m in the western Alps and 900m in the eastern. Later in the week widely at around 2,400m.

 

The 850 hPa charts from today's ECM and GFS are largely in agreement and show the expected weather pattern for the week.

 

Sun ECM GFS

Tue ECM GFS

Thu ECM GFS

 

To those lucky people heading off this weekend - have a great time, take some sun cream, and be very careful if venturing off-piste.

Edited April 2, 2015 by Blessed Weather

[J10]

I was going to make this post yesterday (Weds) but the high winds we've been experiencing in Suffolk this week finally brought down a very large willow tree - right onto the electricity transformer serving my area. So no electricity from mid-afternoon until mid-night meant no Internet. So my apologies to J10 that this post is nearer to his weekly blog than I intended.

 

Anyway, it's continuing to look good for those heading off for the final 'major' week of the Alps season, before many resorts then close on the 12th April. The snow that's been falling widely this week will continue on and off right through until next Monday 6th, so pistes above around 1,700m shouldn't be lacking snow! 

 

Sat 4th Alps Precip Sat04April15.png Sun 5th Alps Precip Sun05April15.png Mon 6th Alps Precip Mon06April15.png

 

Looking at the precipitation charts above, it makes me wonder how snowforecast.com can arrive at the following forecast for La Plagne, i.e. showing no snow accumulation. Meteo France confirm 80% chance of snow for La Plagne on Saturday with freezing level at 1,400m.

 

snowforecast.com showing no snow accumulation?? snowforecast for La Plagne.jpg

 

Thereafter it looks like things dry out and for the French Alps the sun is expected to come out. Austrian & Swiss Alps are looking more likely to keep some snow showers with sunny spells. The more settled weather brings a rise in temperatures during the week as the colder air moves off east, but critically the temps fall below freezing each night, allowing pistes to be groomed ready for great skiing/boarding every morning. At the start of the week afternoon freezing levels around 1,800m in the western Alps and 900m in the eastern. Later in the week widely at around 2,400m.

 

The 850 hPa charts from today's ECM and GFS are largely in agreement and show the expected weather pattern for the week.

 

Sun ECM ECM 850 Sun05April15.png GFS GFS 850 Sun05April15.png

Tue ECM ECM 850 Tue07April15.png GFS GFS 850 Tue07April15.png

Thu ECM ECM 850 Thur09April15.png GFS GFS 850 Thur09April15.png

 

To those lucky people heading off this weekend - have a great time, take some sun cream, and be very careful if venturing off-piste.

 

Great update there as usual Malcolm.

Edited April 2, 2015 by J10

[J10]

Latest update from http://www.snow-forecast.com/overviews/tips_full

 

SNOW NEWS UPDATED 2 APRIL 2015

 

INTRODUCTION It's been a snowy and windy week for the northern regions of the Alps, with plenty of fresh snow falling, particularly in Switzerland where over a metre of fresh snow has been recorded in places. Unfortunately the strong winds have really impacted lift operations with many of the higher lifts in the Northern Alps being closed for the first half of this week. The good news is that the wind eased for the majority of ski areas on Thursday 2nd April.

 

AUSTRIA The recent gift of snow has work wonders for many of our featured resorts as spring conditions were beginning to hinder skiing in some areas. Thanks to the fresh snow many pistes and off piste areas have been revitalised. They are still heavier conditions on resort runs which is to be expected at this time of year but if you're heading out for a holiday this coming Easter then you will be in for a treat. The Ski Welt region of Niederau (50/115cm), Wildschonau (50/115cm) and Alpbach (50/115cm) have seen their depths increase comfortably to provide fresh pistes and pockets of fresh powder. The temperature has been sitting around the zero mark which is great news for the fresh snow. There were reports of light rainfall in the lower resorts, Igls (30/100cm) being one of them but light snow flurries were seen at higher altitude.

 

FRANCE It has been a very mixed week with heavy precipitation in the Northern Alps earlier in the week bringing some wet weather and heavy snow conditions on piste, making off piste challenging, and increasing the avalanche risk. The temperature dropped in the middle of the week providing very firm snow conditions in places. As elsewhere in Europe, strong winds have been one of the most significant factors this week, really limiting the skiing on higher slopes. The winds eased for Thursday 2nd April though allowing many of the recently closed higher lifts to reopen. In the Espace Killy (100/195cm) only 37 out of 79 lifts were operating on the afternoon of Wednesday 1st April. On Thursday 68 lifts were open, really expanding the amount of terrain that was accessible for visitors to Tignes and Val d’Isere. In the Southern Alps and Pyrenees there has not been the precipitation of the more northern resorts, with mostly sunny weather this week providing excellent spring skiing. The forecast for the coming days in France is quite mixed, with sun and cloud accompanied by an elevating freezing level. Further clouds are expected over the weekend in the Northern Alps which could see further light snowfall then brighter weather from Sunday 5th April through the first half of next week. It is expected to be cloudier over this period in the Southern Alps and Pyrenees which could see some wet weather as the freezing level will increase to over 2,500m across the French resorts. Cloudier skies could move back in to the Northern Alps in the second half of next week, and again wet weather could result.

 

SWITZERLAND Large amounts of snow fell at the start of the week and it continued to fall throughout the week. Over a metre of snow has fallen in some areas, improving the overall skiing conditions. When all of the higher lifts open the skiing should be superb on the upper slopes.The resort of Grimentz (30/225) reported up to a mere of fresh snow on Tuesday 31st March and the webcams are showing fantastic slopes and lots of fresh powder. The resort had nearly all of their lifts running. Avalanche warnings are high at the moment so take extra care and adhere to all safety warnings.There are currently strong winds residing at high altitude in many of our Swiss resorts, particularly in Saas Fee (65/320cm), which has been closed recently but reopened on Thursday 2nd April however only 9 lifts were operating.The forecast is predicting the clouds will fade in time for Friday 3rd April but the further into the weekend it could be cloudy yet again but there could also be more snow falling.

 

ITALY Skiing in Italy, as elsewhere in Europe, has been impacted the stormy winds. The good news is that this severe weather has brought fresh snow to many resorts. The Dolomite resorts have not had the fresh snow that the resorts in the Alps have seen but then again they have also not been as affected by the strong winds either Cervinia has been closed for almost all of this week and was once again closed on Thursday 2nd April the resort was closed due to very strong winds Val Senales (35/320cm), another glacier skiing location, has also limited lift operations this week due to the stormy conditions. The good news is that the resort could open more lifts on Thursday and heavy snowfall meant the skiing on offer was excellent, although it was still very windy high up.Firmly packed piste conditions were reported by the Ski Club Leader in the Milky Way resort of Sauze d'Oulx (80/100cm) on Wednesday 1st April. It was a sunny day on Thursday with some light clouds moving over, providing excellent visibility to enjoy the skiing on offer. With 52 out of a possible 69 lifts operating there was plenty of skiing available too.

 

GERMANY The skiing conditions really improved for Thursday 2nd April across Germany with the recent strong winds easing, allowing the majority of the recently closed resorts to reopen. The only exceptions were the Zugspitze ski area at Garmisch (25/415cm) and Lenggries (15/65cm). The Classic area at Garmisch was open on Thursday offering some great skiing. Storm damage means that Lenggries currently remains closed. The conditions at our other featured German resorts were very good on Thursday following heavy snowfall on Wednesday 1st April lasting throughout Thursday. This did reduce the visibility but the fresh snow more than made up for this.

 

EUROPEAN WEATHER OUTLOOK Changeable weather is expected across the northern Alps over the coming weekend. By Friday 3rd April it should be nice and clear by the middle of the afternoon but the weekend is when it will be more varied. Both Austria and Italy should see a mixture of sunshine and cloud, with the odd flurry of snow. Western Italy looks brighter over the weekend but the east should be cloudier with a good chance of yet more snow. Switzerland looks fairly consistent with sunshine on Friday and cloudy and light snow on the Saturday 4th April.

[J10]

The last blog of the season has now been published here. https://forum.netweather.tv/blog/189/entry-4882-alps-weather-forecast-3-april-2015/

[J10]

I just had a look at snow webcams and there was plenty of snow higher up in the Portes du Soleil today.

 

One first glance, a typical spring scene down in Morzine however on closer inspection you can easily see the snow line on the trees towards the top of the Pleney amongst other areas. . 

 

http://www.snoweye.com/grabs/0018/03.jpg

 

Looking at historical webcams there was snow even in Morzine resort level earlier today

 

http://www.bergfex.com/morzine/webcams/c3222/

Edited April 5, 2015 by J10

[Blessed Weather]

With ‘spring conditions’ across most of the Alps this coming week, here’s a good example of the effects of radiative cooling at ground level under clear skies, once the sun goes down.

 

My first chart is from Meteo France and shows the  Monday 6th April forecast for La Plagne at 1,250m. I’ve marked it up to highlight the key aspects. You will see that during the 24 hour period the 0c isotherm (freezing level) rises from 1,500m in the morning to 2,000m later that night. I’ve also shown two GFS 850hPa charts, one for 06.00 on Monday morning and the other for 18.00 in the evening. These confirm that the temperature at 850hPa (around 1,500m) does indeed rise, with the 0c isotherm moving away as less cold air moves in. But meanwhile, the actual temperature experienced ‘on the ground’ in the resort goes in the opposite direction, dropping from +5c in the morning to -1c at 18.00 and -3c overnight.

 

Meteo France GFS 06.00 18.00

 

Today has been a gloomy day in La Plagne, with the cloud base so low most skiing was in the fog. Ironically, as the lifts closed this evening the clouds finally broke and the sun started peeping out. The webcams show an impressive amount of snow there, so the rest of the week should provide fantastic skiing under largely clear skies. Goggles off, fleeces off, sun-cream on, shades on!