Opinion 2015 Season Prediction Thread

Chowder11

Part of the Furniture
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Oct 21, 2003
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Lost me after this:
"The snow came early in 2014 and cold weather kept it from melting away."

Warmest august on record. Never seen so much snow melt so fast...
Was good early, didn't stay though. So 1/2
 

Rush

Pool Room
Jul 26, 2000
45,199
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Lost me after this:
"The snow came early in 2014 and cold weather kept it from melting away."

Warmest august on record. Never seen so much snow melt so fast...
Last snow event occurred on the first weekend of August.
 

Gerg

One of Us
Sep 8, 2001
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Regarding Mr Peterson, we did all this last year ... but one more time:

Peterson: "The line has a slope of 7.0 cm/decade. With (sic) a probable error of 4.7 cm/decade. This is a 1.48 P.E. result, meaning that no slope at all has a 32% chance of being correct."

I don't get "probable error" in the context.¹ No matter, the regression slope is about 7 cm/decade² and the standard error in that is about 4.7 cm/decade.³ And yes, that is a t-score of about 1.48. The rest is rubbish. The probability that the slope is not negative (i.e. that it's zero or positive) is approximately P( t>1.48, 1-tail ).⁴ In fact P( t>1.48, 1-tail, 57df) = 7% ... so where the hell does 32% come from?​

Peterson: "The Kolmogorov-Smirnov Test was used to obtain the probability that the distribution of snow depths had a random distribution, with no linear trend."

Nope. K-S is a test of normalness -- not randomness -- and says nothing definitive about the presence or absence of trends.​

Peterson: "The result of the Kolmogorov-Smirnov Test is that there is 31% chance that the snow depth distributions from 1954 through 2013 represent a random distribution with no linear trend."

The inference is simply wrong. What he's testing is whether the peak depths, taken as a whole, fit a normal distribution with the mean and standard deviation of the sample. I haven't repeated the test, but a 31% chance that they do (or does he mean don't?) could be somewhere near right. But regardless, that says nothing meaningful about the presence or absence of a trend.​


If you really must follow Mr Peterson go right ahead, but be aware that he's mostly talking rubbish.⁵


Notes:
1. The term usually refers to the half-width of a distribution.
2. These days I'd probably exclude the heavily under-sampled 1954 outlier, making the slope nearer 9 cm/decade.
3. Actually it's 4.5 cm/decade (including 1954), but who's counting.
4. Subject to a range of assumptions that aren't quite met here, but near enough.
5. I wouldn't care, except that his plausible-looking but highly erroneous calculations give the impression that the downtrend in our snow depths is statistically very weak. It isn't. In fact, excluding the dubious 1954 peak depth, the probability that there is no downtrend is only about 2.8%. That means that the downtrend is highly statistically significant.
 
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Gerg

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Sep 8, 2001
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And I was still skiing on it at Perisher on the 7th of October.

No, you were skiing on intensely managed, largely artificial snow. (I was there in early October too -- skiing backcountry, and walking a lot.) I agree that it was a "good" season ... by modern standards, which have slipped. A lot.
 

Normo

Mostly Harmless
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Sep 21, 2011
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No, you were skiing on intensely managed, largely artificial snow. (I was there in early October too -- skiing backcountry, and walking a lot.) I agree that it was a "good" season ... by modern standards, which have slipped. A lot.
I agree that Perisher did a fantastic job of managing the snow and providing "artificial" snow whenever possible, but.......there is no snowmaking around Eyre T-bar and we were skiing around there into October.
The big snow event, late June, provided a very good base and while there were only a few follow-up falls, the freeze/thaw combined with very effective grooming/ management, gave us a season that went the distance.
I've got no doubt that Perisher will put in a similar effort in season 2015 to maximise the playing surface for us all. I also recognise that the challenge is getting tougher and that great natural snow events in Australia will become fewer and farther between. The Northern Hemisphere also faces it's challenges, though they have a bit more natural advantage over Oz.
 

Claude Cat

On my bike
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Jul 6, 2001
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From my summary of snow bearing systems last year:

I had a look through the major systems that brought snow this winter. I have not included systems that were rain bearing.

June 23-30 (Snowmageddon I) 50-100cm across all major mainland resorts. A good way to get the winter rocking.

July 4-13 (Snowmageddon II) 50-80cms, a good follow-up to the first system.

July 15-18th: 20-40cms

July 29th - August 1st: 20-30cms

August 16-20th: 20-30cm: favoured higher NSW resorts.

September 1-5th: 10-15cms​
 
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DidSurfNowSki

One of them
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Jan 19, 2014
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No, you were skiing on intensely managed, largely artificial snow. (I was there in early October too -- skiing backcountry, and walking a lot.) I agree that it was a "good" season ... by modern standards, which have slipped. A lot.
@Gerg Whenabouts in April are you putting your prediction up using your Spencers Creek snow depth prediction model - mark IV ?
 

Telemark Phat

Pass the butter
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Jun 21, 2008
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And I was still skiing on it at Perisher on the 7th of October. The big melt didn't start there until very late August. Was a very good season!
My prediction for 2015? I predict that I will be optimistic :D

Mt P fell apart early last year. Perisher did a good job of pushing snow around onto a couple of trails, but the rest of the hill was much barer than it usually is.
 

Normo

Mostly Harmless
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Three fantastic weeks with the rest of the season being average to poor.
We must have been at a different Mt P.
I skied every day of the season (123 days) and my stats were very heavy in Mt P involvement.
2012 was better, marginally. But 2014 will do me any time. I guess it's all in the eyes of the beholder, but I rate it as a great season. Fingers crossed for 2015.
Mind you, I wear mittens so I can keep my fingers crossed all the time! :D
 
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neck_deep

Addicted
May 10, 2011
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Cracking season, close to 30 days (nearly 10 containing at least one faceshot) , several thousand km's working full time and a big smile. If 2015 is as good this little black duck will be pretty content.
 

Boodwah

A Local
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Jun 20, 2006
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Skied May - October = 6 months in the southern hemisphere 2012.
May - Oct 2013 but only b/c skied France June and July when Oz was pretty bare.
Only 5 at a stretch last year which was disappointing considering the great start... pretty much all over by the end of September.
Never skied April, but November a few times.
Here's to a 7 month 2015!
 

PMG

One of Us
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Jan 3, 2011
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Which were the three fantastic weeks in 2013? I call 2013 the little season that couldn't (except for my afternoon with thigh deep freshies on Eyre).
I seem to remember there were 3 weeks that were quite good too. Then it really fell away again. Can't remember which weeks though.
 

Angus_McCrory

Old n' Crusty
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Oct 22, 2005
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2014 had potential.... July was cursed with unstable snow pack for serious BC. Little follow up... and way too short as seesm to be the norm. Can well remember skiing from late June into October when I first started.
 

DidSurfNowSki

One of them
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Jan 19, 2014
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Which were the three fantastic weeks in 2013? I call 2013 the little season that couldn't (except for my afternoon with thigh deep freshies on Eyre).
2013%20vs%202014_zpsr9qiix2m.jpg
 

Telemark Phat

Pass the butter
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Jun 21, 2008
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There were three weeks of snow, but there were still little rain events in August which kept adding a layer of crust. Most of August was dust on crust, don't get me wrong, it was good skiing, but it wasn't excellent.
 

kaegee

One of Us
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Jun 23, 2014
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Its funny how the chart doesn't really tell you what's happened on the ground. The place where the two years intersect at the first week of spring at eg Friday Flat ..13 was grass by the 6 th ....no lift running .14 ..24 cm on the 2nd ran maybe til the season end .
 

Legs Akimbo

Grumblebum
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Mar 3, 1999
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Its funny how the chart doesn't really tell you what's happened on the ground. The place where the two years intersect at the first week of spring at eg Friday Flat ..13 was grass by the 6 th ....no lift running .14 ..24 cm on the 2nd ran maybe til the season end .
The chart is Spencers Creek, a lot higher than Friday Flat.
 

DidSurfNowSki

One of them
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Jan 19, 2014
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There were three weeks of snow, but there were still little rain events in August which kept adding a layer of crust. Most of August was dust on crust, don't get me wrong, it was good skiing, but it wasn't excellent.
Eating Big Eyre burgers under gum trees + top to bottom skiing in the Eyre bowl = excellent skiing IMO. I can't ski powder very well, so it's wasted on me :D
 

Oldie

Hard Yards
May 1, 2002
307
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Outer SE Melbourne
Since nobody has yet posted a prediction with no scientific basis just based on folklore, I submit the following...

Outside my house there is a street tree which has a kind-of miniature apple fruit. This year the tree was absolutely loaded with fruit, much more than usual. Old codger who walks his dog past most days said that that is a sign of a cold winter coming. I hope he is right!;)
 

ScottGN

A Local
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Apr 14, 2010
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Since nobody has yet posted a prediction with no scientific basis just based on folklore, I submit the following...

Outside my house there is a street tree which has a kind-of miniature apple fruit. This year the tree was absolutely loaded with fruit, much more than usual. Old codger who walks his dog past most days said that that is a sign of a cold winter coming. I hope he is right!;)
Those kind-of miniature apple fruits are crabapples, you make jam out of them. FWIW the harvest bounty has been plentiful here in NZ too. Does it augur well for a cold, and more importantly a snowy winter? I've got no bloody idea.
 
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rocketboy

One of Us
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Sep 9, 2010
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Feels average this year. Mild east coast summer, autumn seems normal so far. Plenty of moisture along the coast. Dry west of the divide as it usually is. And down south the usual complaints about the weather and a lack of altitude at Buller. And the usual debate about which year was crappier. All sounds pretty normal to me.

So put me down for 165 cm peaking - sept 25.
 

ice_man

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Aug 21, 2008
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Melbourne
Lost me after this:
"The snow came early in 2014 and cold weather kept it from melting away."

Warmest august on record. Never seen so much snow melt so fast...

Snow stopped falling at the start of August. Rest of month was dry but quite cold in Vic.

Also think this year will be fairly poor - autumn so far has been quite cool in southern Vic but also dry. My bet at this stage is a continuation of that, cold enough but not a lot falling out of the sky. That being said the opposite could happen...
 
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