It had been a long time since the previous storm event, October was an incredibly slow month, with only light rain events and mostly cool weather, it had felt more like the autumn doldrums as I call them, the warm dry period that usually occurs most autumns. However finally we had a low come down, and after triggering some massive storms in NE South Australia overnight, we had some good moisture to work with the next day. Combined with a nice overhead jet, warm temperatures and a decent shear profile and very steep mid level lapse rates, we had a highly unstable atmosphere which delivered widespread large hail, and some of the worst hail damage seen in decades to some areas.
I’m not going to write too much about the other storms that occurred this day but it was a very significant outbreak. Many splitting cells occurred, with many supercells resulting. Large hail was recorded from at least half a dozen cells, with the Adelaide area, mid north, riverland and murraylands and even Kangaroo Island all experiencing this. Damaging winds were widespread, with locally destructive winds in the east extending into NSW and Vic associated with thunderstorms. Two cells in particular were the big ones in this state, one that formed off the eastern Mount Lofty Ranges, originating near Gawler, formed a huge high based supercell which died near the border. The second, forming off the northern Mount Lofty Ranges near Burra, tracked across the Riverland, eventually forming a squall line and MCS which tore through Mildura and kept on going for another hundred kilometres before weakening out and dissipating eventually. This was the cell I was on, and I tracked it from the moment the cap broke.
I had decided to stay behind this cell for a couple of reasons. Given it was out ahead of the trough at this time and after noticing the storms to my west, despite being strong storms lacked any features and just looked grey, I decided to tail it and watch it do its thing. I feel like this was a good move, the structure was far better and more interesting from this side judging by pictures I have seen. At that stage I had little idea it would become arguably the cell of the day, possibly producing a tornado west of Mildura, a long lived RFD driven hailstorm with extensive hail and local wind damage in the riverland, and probably the best lightning show in Australia so far this storm season. Secondly I had work very early the next day and simply could not commit to following the cells interstate to their best potential, would have loved to have been in Mildura for the epicness but I’m more than happy with my day.
The Cap broke in the mid arvo, and I felt the first few drops from this developing cell just to the east of Burra. I had chose this area as a target as I noticed the trough was still well west of where it was forecast, and having been burnt in the past rushing onto the triggerless flats, i decided that my best bet was the ranges of the northern Mount Lofties for something to trigger. I noticed some decent motion in this first cell, with scuddy inflow already occurring in one area. I let it drift to the east for 15 or so minute to get a full view of the updraught, and then basically followed this cell to near Waikerie, watching it gradually become more severe until the drive involved dodging downed trees and litter debris. The anvils from storms to my north completely obscured the updraught of the cell I was on until i was following nothing more than a flickering heavy rainshaft.
I abandoned it soon, and watched an epic lightshow in a featureless sky to the north, before dropping south to intercept a left mover which decided to die 20km short of me, taken out by a rogue right mover by the looks, and then had a new cell develop overhead on the ferry in Waikerie, where 5 flangs in quick succession hit, the closest couldn’t have been further than 150m. All in all a good day, we’ve been a bit spoilt in South Australia this year. Latest estimates suggest this storm has caused at least 100 million dollars in the Riverland, a huge blow for the region unfortunately.
Some impacts of this storm.
Some radar images of the storms.
And finally satellite.