Today will be etched in my memory for a very long time. I have always wanted to watch a Supercell develop over the Dorrigo/Nymbodia area and follow it north through the Northern Rivers. Finally today I got my wish.
I started mid afternoon in Grafton watching the DP's edge towards 21c and wondering when and if the cap was going to break. It was a lot stronger than I was expecting. With every extra minute it held the more I got excited at the huge amount of CAPE that would become available later on. Re-plotting a GFS sounding for Grafton with 34/21 gave CAPE values of over 3000kj and LI's of -8 ... pretty damn nice!
Around 3pm a small line (running E-W) developed from Clouds Creek to Glenreagh. The line continued to look unorganised for the next two hours although one base caught my interest with some slight rotation and a funnel cloud as it died.
My attention turned to the western most base in the line. It was looking a little darker and had a good strong look to it. I was hopeful this would be the one. Thankfully it was. The base was now separate to the downdraft indicating some good organisation. Time to move closer.
I headed down to Coutts Crossing and watched the base separate from the rain curtain even further and take on a more symmetrical shape. Shortly afterwards a wall cloud developed.
Considering the storm should start moving north and increase in speed I took a gamble and core punched south of Coutts Crossing. The base was now increasing in size and looking very dark and green.
I found my way to the RFD which was now starting to circulate around the southern edge of the base. Upon entering the white rain curtain I was greeted with a blast of wind and hail around the 3-4cm mark. 5 minutes inside there was enough, it was time to move north. The cell had become a fully grown supercell and was now spinning its way north towards South Grafton. North of Coutts Crossing I was safely out of the RFD, or so I though. 10 seconds later the wind and Hail roared across the road in front of me. Tree branches were now snapping off and hail up towards 4cm was falling sporadically onto the ground. At this point I tried to find a clearing away from trees and sit it out for a few minutes whilst the main wind core moved away.
I quickly gave a report to the BOM (who I have been advised didn't have a warning out until that stage .... not sure why)and then proceeded north to Grafton again. The wind was still howling however the initial gusts (~100km/h) had moved on. (I was amazed at the stupidity of some people parking their cars under trees trying to protect themselves from hail as branches fell nearby.)
Finally I got out at South Grafton and headed up the highway north. Near Ulmarra I stopped and watched the supercell advance towards me. The Supercell had now taken on the mature stage and looked nasty.
At the time this photo was taken, Swan Creek (7kms to my SW) was being hammered with reported cricket ball hail.
I continued north east trying to get out of the sporadic hail now falling out of the anvil. Finally I broke through however the views were terrible except for the back end of the Casino supercell MB was on.
I ended up heading all the way to Coraki and watched the supercell advance north. Behind me the Casino Supercell was spitting out some intense CG's from the anvil above.
Finally met up with Michael and watched as the two supercells finally ran out of energy.
