Snow
Chase!
Well this is the report I never expected to write! I had been thinking about going down to Stanthorpe during a cold outbreak, and this one looked like the best possibility of sleet/snow so far. Unfortunately, work, uni and other commitments would interfere. None the less, I’m too stubborn to let that stop me, and after some decisions on Thursday morning, I had decided to get up early on Friday morning and head out there. It wasn’t much of a sleep, in bed at 11pm, up at 2am – out of the house by 2:30am! Not to mention it was COLD! 3.4C when I left the house, coldest temperature I’ve ever recorded at my house. After stopping at the service station and filling up on fuel (and being eyed off by the service attendant as this person walks in with a ski jacket over his head and gloves on from the cold), I was off! There was a little cloud evident on the sat pics over the granite belt region, and the 12Z soundings proved moist in the low levels, with the FZL at about 890mb. Just south of Ipswich, I reached negative temperatures (-0.1C), this fluctuated between –0.5C and 6.2C for most of the journey on the Cunningham Hwy. It wasn’t until just north of Warwick at around 4:30am it dramatically fell, -5.3C! There was nothing I could do to stop the windscreen from fogging up except wind down the window! Fortunately, I had taken my dog down to the park the day before and the blanket he sat on was there, so at Warwick I stopped and got the blanket out and wrapped it around my legs. Then I got the spare towel out of the boot and draped it over my head to help keep my face warm. I probably should have setup the tripod and got a photo of me dressed like this, I’m sure it would have provided amusement for all! But it doesn’t matter, it was keeping me warm! Just south of Warwick, I couldn’t see any cloud which was concerning, but I saw a sign that said the highway between Tenterfield and Glenn Innes was closed due to snow, so I decided to keep heading towards Stanthorpe! Stanthorpe looked more promising with lots of low level Cu, some of it with reasonable vertical development! But I thought that I’d had to head further south still. There was the odd patch of ice on the road south of Stanthorpe, temperatures hovered around the zero degrees (-2C to 0C) mark. I stopped off at the BP and talked to a person who was delivering bread (I “undressed” first though!) She said that she had small snowflakes on her windscreen near Tenterfield! I continued to head towards Tenterfield. Dawn was breaking by the time I got to Tenterfield (6:15am) and I saw some CJ’s to the east and west that were precipitating, but there was no way to get there! I was unsure what to do, I really only had aimed to go to Stanthorpe, and I had gone 60km further south then that and still nothing, but I didn’t want to come all this distance for nothing! Since Glenn Innes was about another 100km to the south, and another ~200m in height, I decided to continue down there. I was also hoping to come to the blocked section of the highway. Temperatures now were sitting between –2C and –4C.
About 50km north of Glenn Innes there was an abundance of frost present on the ground, over the next 10km this increased to what appeared to be a combination of frost and snow. I got out of the car to take photos and look around, and then, to my amazement – it finally happened! SNOW!!! I was ecstatic! Only small, fine powdery flakes, but snow none the less! I continued further south and the layer of snow on the ground got thicker...
Until I finally got to Glenn Innes when there was a big jump in the amount of snow on the ground. There was approximately one to two inches covering the ground, there was snow on the roads and the roads were VERY slippery now. I nearly went A over T getting out and walking on the road too from the ice. I pulled over near a park and watched a few families in the field have snowball fights. I made a few snowballs too, but rather then making enemies, I thought I’d be better off throwing them at my car :)
Unfortunately, there was not enough snow to make a Snow-Jimmy, something I was hoping for. The snow present was very soft and powdery, and when you compressed it, it didn’t amount to much! I spoke to a few of the locals (all of them commenting on how I must be feeling the cold because I’m a Queenslander!) It was certainly quite a novelty for me! I had a lot of fun just pottering around and having a look. At about 8am, the snow was starting to melt. I decided to head back to Brisbane at about 8:20am, as it was a 4 and a half hour drive back. Even on the way back, much of the snow and frost to the north of Glenn Innes had already melted. It’s a good thing I didn’t get there any later, or I wouldn’t have seen much at all!
It was an enjoyable drive back to Brisbane, not much traffic on the road at all! All up, the chase was ten hours in duration, and I drove about 780km – well worth it though, and if I have the opportunity, I’d do it all again! Only with a little more sleep this time :) There were two main things present on the charts that (in my opinion) assisted in the cold outbreak extending into northern NSW. The first was the positioning of two upper level highs, one over the Coral Sea and one in the Indian Ocean. This forced the jet down before forcing it northwards over WA, and bringing with it cold air. The high over the Coral Sea assisted in creating the sharp upper level trough, and ensured that as much cold air went in, as as much warmer air went out, again assisting in the advection of cold air. The significant pattern at the surface was the strong ridgiging of a high pressure system over SW WA to the south. This ensured a good flow of cold air at the surface with strong winds and some moisture to the southern areas. Let it snow!!! Many thanks to Jane O'Neill, Michael Bath, Matthew Smith and John Woodbridge for updates and information! |
