Chase Report for Friday the 17/04/98
Conditions had been looking good for about 24hours with a nice ridge of low pressure moving inland. Thursday night brought a supercell to Menzies in the Goldfields which dumped 38mms of rain in 20 minutes and caused localised flooding in the town. My chase started from Perth at approximately 1:30pm Friday afternoon. I would have liked to get away earlier in the day but unavoidable work commitments kept me. I had phoned Barry Hanstrum at severe weather earlier in the day and he told me that the most active part of the trough was around Southern Cross and to areas north of Kalgoorlie ( Menzies ) and that the mid levels were very unstable. Shear and CAPE in the area was excellent. I checked the radar and msl charts before I left and also noticed that the trough was also ridging NE of Perth and it looked like it may be unstable there as well. There was also some small activity in this area already. It was an unusual setup as our summer pattern is for them to ridge down the coast and then inland. This trough was already inland and ridging back to the coast. I took a photo of some shelf type cloud over Perth before i left.
I drove out to Northam on the Great Eastern Highway. There were some small cells on the way but nothing of too much interest. I drove up Mt Ommanney which is just before Northam as this is a good look out with 360' views. To the East along Great Eastern Highway I could see some small cells but again nothing huge, mostly just strata q and what looked like left over anvils from activity that had been and gone. I thought at this stage that I had missed everything and was a little disappointed. However to the West and North West I could see two small cells with rain in the back. The one to my left looked weakish. Nothing was really happening so I stayed put for about half an hour to see how they would develop. I didnt think that I would have the time to get out to Southern Cross anyway. The storm to my right started to look good with a squarish back developing and some good updraughts going. I could also hear faint thunder in it. Things were starting to look up. The clouds had an eerie bluish colour similar to those in the Northam Tornado photos. I took another photo at this spot and thought that I'd head up Avon valley rd. This road ran in between the two cells and so I thought I'd drive north for a bit and just see which developed better.
I got to the Toodyay-Goomalling rd intersection and the storm on my right was starting to take shape so I decided to turn right and head towards Goomalling. The storm started to develop a nice base at the rear and I was only about 1-2 k's SW from the base when I stopped to observe it and take some photos for a while. I noted my position on my topographic map and the time was 4:05pm. The base continued to develop nicely with more definition and I stared to get CC* strikes overhead. At 4:20pm the storm produced a lowed cloud base and slow rotation started. I continued to photograph the wall cloud but rotation never really increased. The was some small scud action happening around the bottom of the wall cloud that I kept imagining were funnels. Not to be. At 4:25pm it started to rain heavily on the NE side of the storm and I could see the cold outflow taking over as the wall cloud was quickly dissipating. The rain looked quite heavy and was heading my way quick and I wanted to avoid being caught in this shower as I would lose my visibility. I later found out from the bureau that this storm was also a supercell. It turned east and lasted for a few more hours.
I wondered how the other storm was developing and turned to have a look. I could not see it but my attention was quickly drawn to a large storm over to my right with a massive lowered cloud base. It was so big! I couldn't believe it . I've never seen a base of a storm so large. Although light was poor I had good visibility of it as there was nothing in between it and my position. I estimate it to be about 5-10 k's across and my distance from it was approximately 20-25 k's, this is hard to judge but from later events I worked out it was about this far away. I wasn't even looking at it for a few seconds and didnt even have a chance to take a photo of it when all of a sudden a cloud drops from it. It came down very fast, maybe one or two seconds to go top to ground, as it hit the ground it sent up a small puff of dust and I could easily see it rotating. I couldn't believe what I was looking at! I thought, my god, that's a tornado! I could see small pieces of debris being flung off it and it as it rotated every now and then I could kind of see through it. It looked like it may have been two separate vortices. I cant say for sure it may have just been clear patches in the funnel. I estimate that it was rotating at about one revolution per 5 seconds. I was so nervous that I was fumbling around with my camera and as it was some distance away my auto focus wouldn't work, so I went to manual. I took two photos and then the funnel changed shape very quickly. It cleaned up in the middle to a funnel about 1/4 of the size that it had been. As it was doing this the outside kind of broke away and dissipated, bits broke off, did half a lap or so and just fizzed out to reveal this neat thin tornado. I took a photo of this and then I stopped to observe it some more. It was raining slightly towards the front of the storm and I think that the cold outflow of this pushed the tornado along the ground. It moved to the right slowly and stretched it out. It then looked like it kind of had been stretched too far and it came off the ground and just roped out back up into the cloud. I quickly took a photo as it was doing so. I couldn't believe it was over. I estimate it lasted only about 90 seconds. I had taken four photos, these aren't great as I have just brought a new camera and only have a 35-80 lens and was a fair distance away. Still its easily visible. I still couldn't believe what I had just seen. I kind of always imagined that if I ever saw a tornado it would be after chasing a storm, watching a wall cloud develop and then a tornado drop, I never imagined to just turn around and see one. The time was 4:30-4:35pm and I was 22k's along the Toodyay Goomalling road and had been looking due West.
I jumped in my car and headed towards the storm. It only took me about 15mins to get within a good distance of the storm base. At one point a wall cloud came down so I stopped took two photos, it went back up and so I kept driving. I was now parallel to the storm and about 5k's south. The hwy was heading away from the storm so I stopped to have a look at my topographic map for any small roads that may head in the direction that I wanted. As I was stopped another wall cloud dropped down. This one was more defined than the first and rotation was faster. It was so close to the ground it was unbelievable. It was almost on the ground and as it rotated bits where hitting the ground but it never really seemed to connect properly, the photos certainly show some small pieces on the ground. I took five photos here.
I then found a road about 500m up, Nunile rd that headed NW exactly parallel to the storm. I turned up it and about one kilometre up it came out on a ridge parallel to the storm and only about 2k's away. I was in perfect position. I got out and started to photograph the new wall cloud. I started to get CG's* within about 1 kilometre or less from me and this along with some incredible loud thunder claps quickly encouraged me to get back into my car. The wall cloud was really starting to crank up and the lighting was coming fast and close. Every clap made the ground shake and sent shivers up my back as it was so close. The wall cloud was becoming better defined and rotation was increasing. It had widened out to about 500m to 1000m across. I could feel the air all around me being pulled in to it. Its the most incredible sight I have ever seen. The atmosphere was just amazing. A weird noise also started to build and I can only describe it as similar to the sound of slow leaking gas only sucking. I thought to myself here we go. I was sure that a tornado was about to drop and I was in perfect position. The time was 4:50pm.
The wall cloud was starting to move away and I headed up the road took a left turn and started to head back in towards it. I was quite close and decided to turn the car around away from the storm in case a quick exit was required. A passing farmer stopped and asked, "what the f--k are you doing, you'll get struck by lightning". I assured him I was safe in my vehicle and he headed off. I was now facing the rear of the storm and noticed what looked like rain in the back. The wall cloud was starting to crap out and it looked like the cold air was taking over and the storm was going to dump it guts in the form of rain and hail. Thinking back now and talking to the guys at the bureau I think that rotation would have had to have lasted about another five or so minutes for a tornado to have formed. I took off as I thought I might be able to beat the rear flank downdraught so I took a few shots of a now ill defined wall cloud, still rotating however and very close to the ground and headed off west. As I got closer to the rain I noticed the tell tale white streaks of hail and I thought uh oh. It started to rain and almost immediately and hail started to fall spasmodically. The time was 5:10pm. Then the rain and hail started to really increase and I had to slow right down just to see where the road was. The next two or three minutes was what I can only describe as some of the most frightening and intense of my life. The hail started to come in heavy and fast, stones were about 1-2 in diameter. The hail wasn't just falling but the wind was driving it. I had to stop the car completely as I could not even see where the road was and were the paddock was. Visibility was about 5m. The wind was incredible, I estimate the speed to be around 140/160 kph. I have been on Gooseberry hill escarpment when they have recorded 106kph winds and I can tell you that this was much stronger. The hail was coming in sideways from my left going from west to east. It was bouncing off the road. The noise of it hitting my car was unbelievable. The wind was, well I really cant describe it, you'd have to experience it, its just not possible to say in words. I felt so helpless. I now have a small understanding of what tornado and cyclone victims must go through. I couldn't see passed the front of the car and I knew that I had large trees to my left and right. I was debating whether or not to get out of my car. One look out the window at the speed and size of the hail made up my mind quick enough. At around this time I thought that I felt my car moving about and so ripped on the handbrake. The wind then tore the tarp off my ute which I found later up the paddock to my east, with all the straps torn off one side. I managed to take three photos of all this as it was happening. It then stopped as fast as it had started and the paddocks just looked like snow with huge streaks of water running down them. As the rain cleared I noticed that my car was on the far right shoulder of the road and a medium sized gum tree with a diameter of about 2-3 foot was snapped off about 3m from my car!! I got out and checked my car for damage. It has clean spots from the hail that should polish out but luckily only small dents. I also noticed slide marks where my car had been pushed across the road several feet. This and the close approximately of the tree just made me feel sick. It was then that I noticed the passing farmers car that had spoken to me earlier was a few hundred metre's up off to the side of the road. I drove up to see if he was alright and he said he was fine. I said to him "did you see all that". He said "I didnt see a f-----g thing". Then he goes "I pulled up over there" and pointed to the other side of the road". His car was off the road and at a 45 angle to the road about three feet from a tree.
I headed back into Toodyay as I was running out of light and I just wanted to be as far away as possible. I phoned my flat mate and explained to him how to get the radar images off the internet for me. He said to me on the phone "are you alright man, you sound like you've just had an accident or something".
So for once I made the right call and was in the right spot. Thus ended my best chase ever and one of the most humbling experiences of my life.