In a country far away and a long time ago, I was sitting in a primary school class (then known as infants school), listening to a teacher explain to us that no two snow flakes were ever alike! Believe it or not I have never forgotten that statement and never stopped wondering about the explanation of ....Why?.........

In a country not so far away and not so long ago, I was tossing about in bed half asleep and in a dreamscape of atoms! -   there were billions of them all moving about, and moving in all directions, then in the middle of this strange vision a few of these atoms bonded together and grew larger very quickly.... atoms were coming from every where and flying into the rapidly enlarging object, then more separate larger pieces started to appear.  Some were revolving around other larger pieces and then others were joining to each other - within microseconds there were millions of flying silvery identities all moving around - some were crashing into others and were themselves smashed to smaller bits which in turn collided with other larger pieces. All this went on for some time, and then a huge star-like object appeared moving through the multitude of smaller bits and sweeping them up - the star shape grew bigger very rapidly and started to fall.... the mist of silvery particles suddenly refocussed before me into a cascade of star shaped glistening objects, all falling downward - some were getting so large the edges were curling upwards and some were folding over on themselves and turning into ball shapes, others lost pieces of their arms, occasionally a gust of wind would blow them all together and they took on the shape of mammatus as they crowded together..........I woke up from my weird dream.......  After all these years of asking Why? my brain was suddenly satisfied with an answer!  I suddenly understood why no two snowflakes looked alike!!

I looked around  the dark room, still  disoriented. I focused on the clock it was 3am..... thirty minutes later I was driving northward..... 

A field of cold air was moving towards Victoria behind a fast moving cold front, a small satellite low had developed west of Tasmania and this would help slingshot the cold air straight through central Victoria - the snow line was expected to drop close to 500 metres. It was only a bit more than an hour's drive into the central hills of Victoria. I was a little puzzled at the rather high temperatures as I passed through Geelong showing 7°C. The near full moon was showing up a band of cumulonimbus edging northward across Bass Strait. Within the hour I was passing through Ballan and the temperature was still rather high at 4°C, why was it so mild? A strong southerly had sprung up and stars shone brightly in the still dark sky. I continued to be puzzled at the weak lapse rate as my altitude increased to above 500 metres, the explanation though was behind me.... Bass Strait! -  the low level flow was being strongly modified by warming after passing over the relatively warm water  off the Victorian coastline which was around 14°C.  No sooner had I travelled a few more kilometres north into the central hills and barely ascended another 100m and all of a sudden the temperature started to fall rapidly, as I approached the local crest of the road along the dividing range at 717m the temperature had declined to 0.5°C. Although I had passed through some sleet a little earlier there was still no snow, but  with the temperature now near zero my confidence was up that it would be cold enough for snow.

As I left the highest point of the road and headed for Daylesford I was suddenly enveloped into an absolute fog of snow, visibility was almost zero, my windscreen wipers became clogged with ice and would barely work, and within minutes the surrounding countryside was white. The arrival of the snow was accompanied by a squall that blew snow dust everywhere, snowflakes cascaded in all directions....it was dreamlike!!! ...as I arrived at Daylesford the ground and town were covered in a magnificent layer of brilliant white, all was transformed. I stopped and pulled over in the main street still deserted except for a baker standing outside his bakery. I stepped outside and was engulfed into the flying crystals -  the coldness made me cough as the sudden shock of cold air filled my lungs. I walked about for awhile crunching the snow underfoot. Soon shivering I made my way back to the car and wiped the snow from the windshield. I left Daylesford behind and headed east towards Trentham, the outside temperature showing  0°C. The trip from Daylesford to Trentham was a nightmare at times, I was blinded by the falling snow as each individual flake flew towards me and almost made me dizzy, the roads became very dangerous and I slowed. In places the snow was so thick it made a strange roaring sound as it was thrown away from the car tyres and under the body of the car. Not far from Trentham the snow suddenly fell away in intensity and in the dim morning light I could see that very little snow had fallen here.

I drove into Trentham and found the town virtually free of snow, within minutes the snow squall arrived, I had driven ahead of the main snow belt and now the town disappeared into a wall of blowing snow, the heaviest I had seen in years, and again within minutes the town was a blanket of white. I drove south to Newbury which approaches 800 metres and I was in a winter wonderland of snow 6 to 8cm thick, and all of it had fallen within the last hour. The roads were treacherous, I found more than a dozen cars abandoned including four wheel drives. Over the next four hours it was Disneyland in the snow, as I studied all the different types if snow from large flakes mixed with freezing drizzle, to snow pellets and even hail, and occasionally without warning the snow would turn to rain even with the temperature near 0°C. Occasionally the sky would grow very dark and then an almighty gust of blowing snow would almost obliterate everything from view. I drove east towards Woodend and as if someone had changed the day I went from snow covered fields to green grass just west of Woodend and the temperature had only risen two degrees. At the summit of Mt Macedon there was 10 to 12cm on the ground and all powdery the strong winds were blowing drifts across the road as the Temperature sank to -3°C (1003m). By late morning the temperatures started to rise and over the next two hours as I drove west through Trentham in heavy rain and sleet, snow still covered the ground - at Musk and Lyonville 6 to 8cm were stilled piled over everything........I returned to my dream,  the vision of my surreal trip blurred with the reality of the day.

Sometimes you need a vivid imagination to understand things, I never tire of such thoughts, I will always want to know why the atmosphere works the way it does and it all starts with one atom!!!!

1: Snowfall at Musk (Wheelers Hill ~800m) near Daylesford - 6 to 8cm       2: Weak sun through retreating snow shower over a farm track - snow depth 6 to 8cm - temp -1.3°C      3: Church at Lyonville ~1400hrs. Lyonville had received about 8cm

4: Snowfall at Newbury     5: Snowfall at Musk       6: The design of modern cars with fancy inlets and spoilers does not work well in heavy snow,as I found out on 28th June 2002. The build up of snow and ice blocked the air intake to the point my engine started to overheat! (even with an air temp of 0°C), also you may notice the right side headlight is covered in ice, I thought I had blown a headlight, there was insufficient heat from the headlight to melt the build up of snow.     

MSL - 4am 28/06/2002                                                       MSL - 10am 28/06/2002

Vic IR - 0630 28/06/2002                                                     Vic IR - 0830  28/06/2002

Vic IR - 0930 28/06/2002                                                     Vic IR - 1230  28/06/2002

Melbourne Sounding - 10pm 27th June

Melbourne Sounding - 10am 28th June

Locality map around Trentham

 

JCU IR image - ~0429AEST