Snow Watch 2012

We are sleeping at Ifidi cave 16 June......

@ MtTiska - Care to give us an educated guess?

Hi Boerkie-
check the forecasts five days before 16 June and in the days leading up to 16 June if possible. These are called the deterministic forecasts. Any forecast of the precise weather conditions (e.g. snow in morning of 16 June) prior to about 10 June will be rubbish. The closer to 16 June, the better the forecast of 16 June.

The next best is the statistical chances of getting snow in mid June based on previous events. That's like saying Boks will beat England in Durban on 9 June because we've beaten them x times out of y in the past. In this method, the current form has no bearing on the statistical probability of winning. Different teams played in the past and there were different coaches. Hopefully we now have a better coach. In the case of the snow, the previous events have no real bearing on whether there will be a big high pressure over the subcontinent on 16 June (and so no snow) or two cold fronts following each other (in which case the second front can often bring snow). Hope this helps.

Hi Boerkie, two years ago, end of July, Snowforecast.com showed the whole berg in green and patches of orange (5-10cm of snow)so we decided, last minute, to drive up to Sehlabathebe. The day before we left, Table mountain, the Tsitsikamma mountains and the Karoo got snow, and the forecast still looked solid for the berg, so we thought our chances would be almost 100% of getting snow. The morning we left, it was pouring with rain all the way to East Londen, by now we were getting really excited, but to our horror, as soon as we crossed the Kei, the clouds made way for blue skies, and we could see this massive cloud bank just moving out to sea, taking all the chances of snow away with it. The hike ended up being a typical dry winter hike with no clouds at all, or snow for that matter.
So even the predictions aren't always spot on.

Nice example Plouw.
In that case, a mechanism was needed to budge the very large High that sits over the sub-continent in winter and maintains the blue skies and that mechanism was wrong in the forecasts.

Loads of cold fronts move through the W.Cape but the waves in the upper air maintain the high over the interior so preventing the action from passing over Lesotho. Interactions between the waves are intricate and depend on very small changes. This is where that forecast most likely went wrong. There isn't much data to the west of SA to stick into the models at the start of the forecast process. In fact most of that data is essentially invented by fancy statistical routines.

Email conversation between myself and another first timer on the GT this year prior to leaving:

Her: what equipment are you taking in case it snows?
Me: I have the standard waterproof stuff, but not worrying about snow - it rarely snows in late April and its usually melted within an hour any way.

GT Day 1 - sleet
GT Day 2 - small snow fall, as per my prediction it was all gone in a few minutes
GT Day 3:


Day 6 was the last time we saw that snow - in the shade on the side of Mafadi, small bits of it hadn't melted yet...

To paraphrase what Gary Kirsten said at the coaching clinic I attended last weekend: "all I know about life and statistics is that predictions are almost always wrong"...

Yes! I'll be in the berg this weekend and the next. I see the forecast for Saturday, Mont Aux Sources -12!

there is a light snow prediction the weekend of the 22/23 June according to Accu Weather.com, and im meant to be doing Rhino Traverse.

wonder what this weekend holds, weather reports are suggesting some snow - I'll be in the Highmoor/Kamberg area...