Avalanche Awareness and off piste skiing tips from Henry's Avalanche Talk

Keep informed - Big high pressure, an early spring before winter returns

Since we last wrote there has been another 10-20cm.  the season rides on.   

 

Weather

There were big winds and a little snow on Tuesday. (See Andreas report below)  The bulletin points out that there may be some wind slab especially higher up

 

There is a huge high pressure (1040MB) dropping in now and it looks to be settled for all of next week.  Any snow or rain will be confined to the Eastern Alps and Austria.

 

So welcome to an early spring.  Lots of sunshine mild afternoon temperatures, Snow re freezing at night.  We could see spring like conditions next week.  Cold powdery snow where it is high and north facing.  Sun transformed snow on South ish facing slopes.

 

Next week offers the prospect of beautiful skiing, but you will have to hunt intelligently for good off piste - there will be plenty to be found.

 

If you believe long term weather models, they show winter returning from 4th or 6th February.  If they are right there will be lots of fresh snow for the half term school holidays

 

Safety

The snow pack seems to be stabilising (see Henry's comments below).  But look out for slides on the south side is the sun starts to have a big effect (wait and see)

 

Look out for wind slab on the North sie following the big winds on Tuesday as per the bulletin, but they say this is limited in scope.

 

As always you need to apply judgement at all times

 

Looking for the best snow

We gave this advice last week, but it seems even more relevant given the weather forecast for next week, so I left it in.    With the warmer weather that is forecast and a lot of sunshine next week.  It will be more important to look at slope aspect when you are judging where to find good snow.  At this time of year south east to south west slopes catch the sun and this will change the snow as the temperature goes up.  Slopes from north east to north west remain largely shady and it is here that you will find more powdery snow.  This is very apparent when you ski down gulley's and the character of snow changes as you ski from side to side.  Remember that is is not just slope angle but also slope aspect that affects how the snow responds to the sunshine.  Steep North facing slopes get no sun.   Low angle north facing slopes get oblique sun,  Low angle south facing slopes get some sun, but steep south facing slopes get intense solar radiation.  You can observe the effects of this by noticing the different types of snow you encounter as you ski around.

Still complicated but great fun

Today was the best day I have had for some time.  30cm fresh powder and glorious sunshine
See pictures in the La Plagne photo albums

La Plagne declared a risk factor of 3 today and it seemed like there were no slides triggered by skiers despite many people going on steep slopes immediately after the snowfall and against the advice of the Piste Patrol

The snow is stable in many places but we also saw a number of natural avalanches on slopes above 40 degrees on all aspects
On SE aspects we saw the snow continue to slide off the grass and cracks appear.

So watch out the situation remains complicated. 
More snow Monday night

Complicated situation evolving

Since we last wrote there has been at least another 30cm of new snow.  When the recent snow fell it was wet and heavy (see Roddy's reports)

 

Also we just heard on radio that English snowboarder got killed in avalanche in Tignes in the Tufs couloir. When we get some more info, we will post it on the blog.

 

It is now a complicated week for conditions and stability.  The risk level is 3 above 2000m.  This means that natural avalanches are unlikley but a single skier could trigger an avalanche when on any 30 degree or steeper slope oir when crossing at the base of a steeper slope.

 

There have been relatively few slides given how much snow fell, but be careful, as well as the Tufs incident today we know of another incident on the orientation table route on Bellevarde where a seasonnaire got taken over a small cliff and survived but was very shaken.

 

On the brighter side, the wet and heavy snow has all dried out above 2000m due to a dry clear night and there is plenty of nice snow to be had if you know where to stay safe.  If you are not sure play on lower angle slopes and keep an eye out for steeper slopes above you or convexities below you.

 

The Guides may be seen on the steeper slopes, since some of them are OK, but if you do not know how to tell which is OK and whihc is not then play safer when the bulletin shows a risk level fo 3.

 

The situatrion is likely to change rapidly but it is hard to predict.

 

If it stays warmish as forecast for the next 2 days, then the current snow will settle well and form a good layer for the next snowfall to bond with.  But this may not happen and our big advice is to track the conditions each day to see how the base layer evolves.  If you do that, then you will be in a stronger position to judge how unstable the situation will be when the next snow arrives on Friday night Saturday morning.

 

We are expecting some good colder snow on Saturday early morning provided the cold front from the west makes it through to displace the southerly weather system we have predicted for Thursday and Friday.

 

The longer term outlook shows more snow later next week on Monday and Wednesday.  There will be plenty of great skiing to be had.  Spotting where it is safe is a bigger challenge.

 

2 top tips

Track what happens to the current snow as the weather changes over the next 2 days

Stay on lower angle slopes if you are not sure about the risks until it is clearer that the risk levels have subsided.

 

Finding good snow in variable conditions

Having been out around Bellevarde and Tignes over the past 3 days, we have seen a marked change due to the effect of a southerly wind.  On Monday this wind reached 50km/hr above 2500m.

it is now 7 days since it last snowed and the temperatures remain very cold -10 to -15C so the snow is holding up well and remains in fantastic condition on the pistes, but if you are going off piste you need to look harder to find the best snow.  It probably requires expert guidance to work it out now. 

The recent snowfall fell in a NW wind or no wind.  This south wind is re arranging the snow.  Much of the obvious off piste is quite enjoyable but the condition is variable between, wind blown, wind crusted, slightly sun crusted on the south facing and some delightful patches of powder.

The Meteo France Bulletin tells us the snow pack is stabilising and the risk factor is now level 2 .  Keep an eye out for wind slab created by this southerly wind.  The bulletin tells us to be careful of the NW facing slopes.

We are expecting  glorious sunshine on Thursday and then some sun and cloud and milder weather this weekend.  Some forecasts say there will be snow, but this seems unlikely.

 

Some weather models point to a classic cold front coming in from the NW on Tuesday in time for Christmas.  But not all models say this, so we will have to wait and see

it is now 7 days since it last snowed and the temperatures remain very cold -10 to -15C so the snow is holding up well and remains in fantastic condition on the pistes, but if you are going off piste you need to look harder to find the best snow.  It probably requires expert guidance to work it out now. 

The recent snowfall fell in a NW wind or no wind.  This south wind is re arranging the snow.  Much of the obvious off piste is quite enjoyable but the condition is variable between, wind blown, wind crusted, slightly sun crusted on the south facing and some delightful patches of powder.

The Meteo France Bulletin tells us the snow pack is stabilising and the risk factor is now level 2 .  Keep an eye out for wind slab created by this southerly wind.  The bulletin tells us to be careful of the NW facing slopes.

We are expecting  glorious sunshine on Thursday and then some sun and cloud and milder weather this weekend.  Some forecasts say there will be snow, but this seems unlikely.

 

Some weather models point to a classic cold front coming in from the NW on Tuesday in time for Christmas.  But not all models say this, so we will have to wait and see

What a week! now for the sunshine.

With off piste skiing, it seems we are either waiting for more snow or fretting about the avalanche risk.  At the moment I would worry about the avalanche risk.  Val is reporting level 4 risk after a week in which between 1m and 1.5m of snow fell and fell rapidly not slowly.

Dom and his friends sucking up the powder in the Grand Montets near Chamonix today
see Cham photo album

 

The most stable conditions are created when the snow falls steadily in small amounts 10-20cm at a time and builds up slowly.  What we have now is 1m of fresh snow on top of a weak layer (especially above 2200m).  Above 2200m there has been no warming or rain.  Below that level the temperatures have been more volatile. which will stabilise things a bit more.  However from reading the bulletin great caution is needed every where.

 

Risk level 4 means it is possible to trigger a slab avalanche on a steep slope when you are on a less steep slope below it.  So with this risk factor, you not only need to avoid slopes greater than 30 degree angle, but you also need to ensure you do not ski too closely underneath a steep slope.  Or if you do, ski quickly lightly and one at a time, ensuring you gather together in islands of safety.

 

The outlook is for stable cold and sunny weather as far ahead as the forecasters can reasonably predict.  So a great sunny cold weekend awaits.

 

 

Future ezines will be on Thursdays - next one on 19th December

Weather forecast Val d'Isere

Issued Wednesday, December 12, 2007, 19:30
Status and trends
The anticyclone sticks
Sustained dry and cold (at least until Tuesday night).
The snow and cold is tempting but dangerous over 1700m.
There will be ample time to enjoy later.

Tomorrow, Thursday, Dec. 13:
You can still see low clouds linger, but perhaps less
Today. The sky was clear in the mountains, day and night, and a little windy
in the east.
Pressure 1032 mb
In plain: -5 / +6 ° C, low wind East
At 1500m off-: -4-> -1 ° C, wind ENE / 8 knots then low
At 3000m off-: -8 ° C, wind Est/14-> 9-> NE/15 knots
Iso 0 °: 100/1400m
Iso -10: 3300-> 3900m
Iso -20: 4800-> 5300m

Friday, December 14:
The northeast wind becomes strong enough in altitude.
Some clouds are possible without consequence in the afternoon.
Pressure 1034-> 1030 mb
In plain: -5 / +6 ° C, low wind NE
At 1500m off-: -1-> -4 ° C, wind NE/9-> 13-> East / 8 knots
At 3000m off-: -5-> -9 ° C, wind NE/15-> 28-> (night) 23 knots
Iso 0 °: 100/1500m
Iso -10: 4000-> 3200m
Iso -20: 5300 -> 4900m

Saturday, December 15:
Perhaps partly cloudy on the Southern Alps, but not here.
The cold increases, the wind decreases, the valleys of the south can lug of
The afternoon clouds.
Pressure 1029 mb
In plain: -7 / +4 ° C, low wind
At 1500m off-: -4-> -8 ° C, wind Is> SE / 7 knots
At 3000m off-: -9-> -15 ° C, wind NE/20-> SE / 9 knots
Iso 0 °: 0/900m
Iso -10: 3100-> 2000m
Iso -20: 4900-> 3900m

Sunday and Monday
Beautiful and cold in a moderate easterly flow.

Weather Forecast Savoie Haute Savoie

Issued Sunday, December 9, 2007, 19:16

Tomorrow, Monday, December 10:
It rains frequently with snow above 1200 and 800m, fairly abundant
Around 2400 in a strong westerly wind and Northwest more moderate.
The contribution of snow expected exceeds hardly 25cm for the day, contributing
Yet the accumulation of slabs.
Pressure 1001 -> 1014 mb
In plain: 5 ° C, wind SW/10-> West / 6 knots
At 1500m off-0-> -3 ° C, wind Ouest/20-> NW/14 knots
At 3000m off-: -10-> -12 ° C, wind Ouest/35-> NW/24 knots
Iso 0 °: 1300-> 900m
Iso -10: 2900-> 2500
Iso -20: 4100m

Tuesday, December 11:
The cold increases, 
There is still a little more snow in the morning from 500m
(+10 / 15 cm on average mountain)
Pressure 1014 -> 1025 mb
In plain: 3 ° C, wind WNW/6-> NNW/10 knots
At 1500m off-: -3-> -6 ° C, wind Nord/14-> 18-> 14 knots
At 3000m off-: -13 ° C, wind Nord/25-28 knots
Iso 0 °: 1000-> 600m
Iso -10: 2400m
Iso -20: 4000m

Wednesday, December 12:
The air is much drier, the sky was clear from the night to 1600m and

Pressure 1026-> 1032 mb
In plain: 0 / 3 ° C, wind north / 7 knots decreasing
At 1500m off-: -6 ° C, wind NNE/14-> ENE / 9 knots
At 3000m off-: -13-> -9 ° C, wind NE/24-> 10 knots
Iso 0 °: 500-> 900-> 0m
Iso -10: 2500-> 3200m

Thursday
Good weather calm, cold still significant risks.

Weather forecast 5th December

Issued Wednesday, December 5, 2007, 15:25
 
Status and trends
The weekend looks perfectly Atrocious;

   
From 1800 to 3000, the heights of snow seem to vary from 30 to 90 cm, which is
good for the season.  See our snow depths webpage for tracking data on this

   

Thursday, December 6:
Rainfall continued in the north Alps with warm night
Early returns in the mountains in a fairly strong wind from the north, but the valleys
Although likely to remain encumbered by clouds this will Scatter the afternoon while thick veils invade the skies at High altitude. The night becomes very cloudy at all altitudes

Pressure 1025 mb
At 1500m off-: 0 / 4 ° C, wind NW/10-> (night) WSW / 9 knots
At 3000m off-: -7-> -2 ° C, wind NW/20-> 30-> 15-> 20 knots
Iso 0 °: 1600-> (night) 2400m
Iso -10: 4100-> 4700m
   
Friday, December 7:
The rains came during night and north of 45 degrees latitude  all day. We must look at the snow over 2000m, but The night temperatures fall and snow must reappear to 1200m at midnight.
Pressure 1021 -> 1011 mb
At 1500m off-: 5-> 0 ° C, wind Ouest/12 knots
At 3000m off-: -2-> -11 ° C, wind WNW/26-> 20 knots
Iso 0 °: 2400-> 1300
Iso -10: 4700-> 2800m
   
Saturday, December 8:
Precipitation should be extended throughout the morning with the
Snow 900m and calm in the afternoon, with some thinning of
Consolation.
Pressure 1011 -> 1015-> 1008 mb
In plain: 3 ° C, wind NW/8-> faible-> SSW / 8 knots
At 1500m off-: -1-> -4-> (night) +2 ° C, wind NW/17-> faible-> SW/16 knots
At 3000m off-: -13-> -3 ° C, wind NW/28-> 22-> 34 knots
Iso 0 °: 1300-> 800-> (night) 1900m
Iso -10: 2700-> 2400-> 4400m
   
Sunday
Precipitation from morning to night in a strong wind from west to the mountains. The iso 0 °
Should the yoyo between 1200 and 2300m with a severe chill in the evening.
To this day, one can fantasize about bringing 45cm of snow at 2700 m.

Promising start to December

The snow arrived ..... finally.  Last week we told you it would snow at the weekend.  What actually happened was it started snowing on Sunday evening at 20.00 and did not stop until Tuesday lunchtime, so the situation is quite transformed and the best we have seen it in early December for 10 years.  (see our snow depths tracking page)

Snow news

That is not all,  The snow is forecast to come back with a vengeance this weekend and especially on Sunday.  Temperatures may fluctuate considerably bringing rain below 2000m for a while.  But there will also be snow down to 1000m at times.  This makes it very uncertain how stable the resulting snow pack will be, we will need to study the bulletins to get the opinion of the experts.  Large falls of snow in a short time tend to be unstable, but fluctuating temperatures will stabilise the pack more rapidly.  The situation is further complicated by the very high winds. which has stripped some higher exposed places and dumped the snow in others creating wind slab.

There was also some surface hoar and evidence of a breakdown of the snow pack before the last snowfall.  So be careful, study the bulletins (on our web logs.) and read ski diaries from Henry and Wayne Watson of Alpine Experience

Weekly weather and snow reports starting today

Welcome to a new ski season.  The first weekly ezine from Henry's Avalanche Talk has gone out.  The snow and weather Gods are being kind to us and will allow the lifts to open in Val d'Isere for the opening day on Saturday 1st December.   At HAT we have been busy preparing for a new season, I know that Henry and Andreas are looking forward to meeting many old friends and new faces for this season. 

Snow news

There has been much excitement in the press and amongst tour operators about the new snow that fell in November.  The truth is this mainly affected Switzerland and Austria.  Recent mild weather has depleted snow depths in France.   But we are expecting a major new fall of snow this weekend.  This time it is forecast to come to the French Alps. This should see us off to a perfect start.

The really good news is that with the fluctuating temperatures, the snow is well bonded to the slope and should form a good base for the new falls this weekend.

New information services

We have completely revamped our web based information services.  In addition to this weekly ezine, there are now 4 new blog sites.

Henry's ski diary -  see Henry's discussion of what it is like out there

Val d'Isere - updates on current conditions, photo albums and avalanche forecast translations

Chamonix - updates on current conditions, photo albums and avalanche forecast translations

HAT blog - posts of the ezine articles on avalanche awareness and general HAT news

Each week in this ezine you will find an update on the snow conditions, avalanche awareness tips, weather forecasts, and a translation of the Meteo France off piste safety bulletin.

Looking forward to catching up    Future ezines will be on Thursdays - next one on 6th December

Weather forecast

Wednesday, November 28:
Night generally clear and plain cold and sunny day without
Wind rather mild for the season in altitude.
It is barely a few clouds high are possible in the late afternoon.
Pressure 1024-> 1020 mb
In plain: 1 / 11 ° C, low wind SE
At 1500m off-: 2 / 4 ° C, wind SE> SW / 5 knots
At 3000m off-: -2-> -4 ° C, wind NE/5-> faible-> NW / 6 knots
Iso 0 °: (700 +2500) -> 2200-> (600 +1800) m
Iso -10: 4300m

Thursday, November 29:
Another beautiful day, cooling and may be
low nighttime fog.
Pressure 1015-1019 mb
In plain: -1/10 ° C, low wind
At 1500m off-: 2-> 0 ° C, wind faible-> North / 8 knots
At 3000m off-: -4-> -7 ° C, wind NNW/7-> 15 knots
Iso 0 °: (400 +1600) -> 1900-> (700 +1500) m
Iso -10: 4100-> 3800m

Friday, November 30:
Returning a moderate northerly winds at altitude and threatens to cloud around 1500m on
Morning and evening high altitude from the north.
Pressure 1017 mb
In plain: 2 / 11 ° C, low wind
At 1500m off-0-> 3 ° C, wind NNW / 6 knots
At 3000m off-: -6-> -2 ° C, wind Nord/18-> Ouest/14 knots
Iso 0 °: (800 +1500) -> 2000-> (1100 +2000) -> (1600 +2500) m
Iso -10: 4000-> 4500

Weekend
First wave of precipitation on Saturday morning making snow at 2000m.
Second wave more intense and lasting Sunday with snow at 1400m, in abundance
Above 2000m, but blown around by the storm to West