The Mountainwatch detailed forecast is provided by our in-house team of alpine meteorologist Aaron Cook and mountain forecaster Steve Lee. This forecast is issued three times per week and updated as required. It's intended to provide an additional human element to the automated forecast data provided above. Sometimes we won't agree exactly with the model data - but if we ever call something significantly different we'll do our best to explain why. Got feedback for us on our fine forecasts? Email aaron@weathersense.com.au and fire away.
Australian Alps Forecast Analysis
Thursday 2 September 2010
By Steve Lee and Aaron Cook
Summary:
Not a lot of good news to give you all in this forecast period. A day or two of mild and dampish conditions into the weekend then a whole bunch of rain and wind is expected Saturday. Our model is saying anywhere from 50mm across the NSW resorts, 60-70mm in Hotham and Buller and a staggering 99mm in Falls Creek, no wonder there is a big Hydro electricity dam at Falls! Add strong warm wind to that, and damage to the snowpack will be inevitable.
Bust out the superlatives, cats and dogs, build an ark, all of that. To make matters worse, it will be a warm rain too. Freezing levels will be around 3500m, the highest in some time.
So what can we expect this to do to our beautiful snowpack, no doubt it will certainly shrink somewhat. Our saving grace: the snow is deep and mostly dry, so it will have the capacity to absorb a lot of that rain. It will certainly be beat up, compressed and packed down (not always a bad thing), however with warm and strong winds the peaks and ridges will bear the brunt and I suspect it will go close to taking some of the most exposed areas right back to terra firma.
We can however rest a little easy. While it will certainly be no fun while it happens, it is in no way a "season-ender". All resorts have 1.5+m of natural snowpack and across manmade areas anywhere up to 2.5m. We will comfortably ride this rain event out. Come Sunday/Monday the groomers will have pushed the snow around, dragging some out of stockpiled areas behind snow fences and sheltered areas and spreading the deep manmade cover to repair and rebuild our favourite runs. A few days of nice weather next week and the weekend's rain will be a distant memory.
Post weekend we have some nice spring weather on the way to enjoy. Following the snow loss this weekend we will still enjoy pretty good cover especially across the vast manmade areas, so September is on track to deliver us some great spring conditions.
Synoptic Outlook:
The last few forecasts have been straightforward. This one is not. The general story is that we start with a weak southerly flow on Thursday, but a big juicy low pressure system is going to form out of a trough lying over central Australia. This low will drag winds north-easterly over the resorts Friday.
Freezing levels are going to skyrocket with the northerly flow, then on Saturday, when the centre of the low is lying over western Victoria there's going to be some Old Testament style rain over the resorts. There will be some relief on Sunday when the flow turns southerly again.
Thursday 2 September:
Weak southerly winds and a shower/snow flurry or two.
Friday 3 September:
North-easterlies develop and there could be a shower or two.
Saturday 4 September:
You don't need skis - you need a kayak. Get the picture? 100mm of rain today won't be a surprise, especially in those areas that like a strong northerly. Expect winds of 70km/h gusting 100km/h as well.
Sunday 5 September:
Winds will be south-westerly and the freezing level down to 1800m by midday, so we could see 8 to 12cm of snow.
Extended Synoptic Outlook:
A high pressure system looks like it will develop, leading to a couple of days of mostly fine weather before northerlies redevelop Wednesday.
Be sure to check the daily condition reports and forecast info and maps daily to keep your finger on the pulse.
