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Spring 2009 Weather Prediction
Posted: 08 January 2009 10:22 AM  
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From Kairn.com

http://www.kairn.com/news_nature_66547.previsions-meteo-experimentale-mois.html

January 2009
Cold dissapates rapidly on the weekend of 10/11 Jan with the arrival of a west then south westerly air stream bring sunny and warmer weather to the Alps, sometimes springlike.

February
A regular high pressure centered over the north of Europe brings springlike and dry weather however a weather front bring snow is possible. Cold in the morning. Temperatures warming in the second half of the month with an early start to Spring.

March
Unsettled seasonal weather with very springlike weather. Sun and warmth, heat even.

April
An atlantic high pressure will bring hot and sunny weather. A month between a hot spring and warm summer.

May
An atlantic depression will bring warm unstable air with storms at the end of the day. High summer temperatures.

June
Similar to may, very hot unstable and sometimes stormy weather. Some long hot days that are not broken by storms in the evening.

July
Low pressure over Spain brings hot stormy weather.

August
Potential heat wave.

Now I must go back and check the Winter 2009 predictions!

 
 
Posted: 08 January 2009 02:14 PM   [ # 1 ]  
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Heat and more heat! Sounds like I need to swap my skis for a wakeboard… The only mention of cold is in the very first part of the first month…

 
 
Posted: 08 January 2009 02:39 PM   [ # 2 ]  
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davidof - 08 January 2009 10:22 AM

From Kairn.com

August
Potential heat wave.

I bet you need a PhD to be able to forecast that.

I wonder why these seasonal forecasters never show a track of past “predictions” and the comparison with the real weather.

Honestly, I value these as much as the horoscopes.

 
 
Posted: 09 January 2009 02:51 PM   [ # 3 ]  
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I think the researchers who are really into this don’t publish specific forecasts.
Instead they run there models lots and lots of times with perturbations of the starting data—to get a _distribution_ of projected outcomes for Temperature and Precipitation—then publish maps that show deviations of the distributions from historical averages.
Last I checked they were showing normal Precip distributions for the Alpes du Nord this winter + spring, with Temperature distributions a bit on the warm-ish side, similar to how its been for the last several years.

Ken

 
 
Posted: 16 January 2009 12:29 AM   [ # 4 ]  
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The serious researchers did another large set of runs of their models to get a distribution of Precipitation and Temperature possibilities. For the Alps, looks mostly like the previous set of runs from last month:
Precip distribution about like historical norm.
Temperature distributions into April shifted to a bit warmer than long-term historical (or we might see “typically” warmer like in more recent years).
But then around May the distributions are shifting toward significantly warmer than long-term historical for Switzerland and Tirol + nearby northeast Italy, and more notably warmer for most of the Alps of France and nearby northwest Italy.

My take on this latest difference getting into May is that snow coverage for high tours depends more on Precip than Temp, so it’s a reasonable bet to hope for good tours in late April + early May—but maybe more hiking w carrying skis to get to them.

Anyway, all that is just skewing of distributions (which I don’t think are strictly even probability distributions). The reality later this season will be what it will be—and lots of times the actual outcome is very different from the center of the hump of the projected distribution.

Ken

 
 
Posted: 24 February 2009 02:27 PM   [ # 5 ]  
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I am so happy that these long term weather predictions are worth absolutely nothing!!

Here in the Northern French Alps and in Western Switzerland the snow conditions have been better than I’ve seen in years. Media reports are saying that for Switzerland, most weather stations are reporting more snow accumulation than we normally get for the entire season. Some are even close to twice the ammount (Ticino and central Switz). What’s most amazing, is that low level resorts (900m to 1200m) in the Jura have literally been running without interuption since christmas.

So not only has it been cold in Dec to Feb (right around the 20 year average), but on top of that the precip is largely excessive of 20y averages in most areas.

I appreciate meteorologists developing their complex models (and hope they succeed!), but for the time being I believe it is safe to consider that they are a long way from any “usable” long term weather forecasting.