T a k i n g   A u s t r a l i a   b y   S t o r m !
Thunderstorms ~ Storm Chasing ~ Severe Australian Weather ~ Media

...from Aussie Storm Chaser David Simpson ~ Melbourne Australia

↑
top

↑
top

↑
top

↑
top

↑
top

STORMPLANET - Severe Event Reports Storm Chase!!


October 15th 2003
Tocumwal & Urana Supercells

This map shows the main path taken for the journey.




Scattered showers and thunderstorms were forecast in the far west of NSW, extending east to the central west and southern inland during the day,  with isolated showers and storms about the south and central coast and ranges in the late afternoon.

0500 Satellite:



0500hrs MSL Analysis (clickable)


0300Z AVN Lifted Index & CAPE plots for the region (clickable):

0600Z AVN Lifted Index & CAPE plots for the region (clickable):



Radar Images

Here's the 0550UTC PPI scan and a corresponding cross-section (RHI scan) which illustrates the 3-dimensionality of the Urana storm.
The RHI scan clearly shows a bounded weak echo region.

Click either image for high-res. Images courtesy BOM NSW.
 

Click here for radar sequence with tweening, at higher speed.

Click here for radar sequence with tweening at slower speed, showing small right mover north of Tocumwal & two left-movers, the Urana cell and the left-mover between Dookie & Wangaratta

Click on any image to below to view, shows 0350UTC to 0700UTC

Timeline 15th October: All images clickable for larger version.

0700hrs: Departed Yarra Glen under cover of Ac, Sc & some Virga.

At 1320hrs this was STA was issued by BOM:

TOP PRIORITY FOR IMMEDIATE BROADCAST
NSW SEVERE THUNDERSTORM ADVICE

Issued at 1:20 PM Wednesday 15 October 2003.

The Bureau of Meteorology in SYDNEY has issued a Severe Thunderstorm Advice
for people in the following weather forecast districts:
Upper Western, Lower Western and Riverina.

1330hrs: Between Barooga & Strathmerton the deck has cleared and a to my NW a line of convection draws my attention:

Soon afterwards one cell looks to be fairly well structured towards the Tocumwal/Finley direction, with frequent lightning static on the radio so I head off to take a closer look.

1350 hours: Stopped in Tocumwal to observe the cell, these two images although from a greater distance show the overall cell as it develops and the inflow band. Later confirmed as a right-mover Supercell, hence the typically smaller size of the cell.

 

Now somewhat closer, strong curved inflow here from the South:
  

I was amazed how quickly this wall cloud formed and started rotating, basically before my very eyes with quite a lot of differential flow in the updraft region as well. I was on the look out for any funnel that may appear from the wall cloud but aside from a couple of possible beginnings, no visible signs of anything on the ground at the time I intercepted:

 

Video from Tocumwal, shows developing & rotating wall cloud. 855kb.

Pan shot showing strong inflow and wall cloud:

 

Mamatus on right hand side & front under Anvil:



Updrafts to the NW of the cell and another cell under development to the south:

 

As the cell drew closer to me more frequent lightning & thunder was observed.

1415hrs: Drove around to the NW flank of this cell, stopping about 3km north of Finley on the Newell Highway. Drove through some small hail and very heavy rain but well clear of the core of the storm. Decided to keep going as I had hoped for a more impressive and easier to access cell further to my North or NE.

THE URANA CELL

1450hrs: On the move again between Finley & Jerilderie, I saw an impressive cell (which I now refer to as the Urana cell) towards Jerilderie/Urana region with quite a dense rain/hail shaft which was outwardly curved indicating a strong downburst or microburst wind (below right). One funnel-shaped lowering curved to the left of the rain shaft with smooth edges and solid form and remained for about 90 seconds before blowing out. From this Southern vantage point adjacent to the inflow region I was unable to properly see the overall structure nor the top of the cell but stayed around for 30 minutes or so to watch development.

Video: Shows rain/hail core in time-lapse. 552kb.

Rainbow fairly low on the horizon adjacent to another nearby storm:

Another cell off to the SE of the Urana cell:


 

1525hrs: Back on the road again to gain a better vantage point for this cell. Driving through Jerilderie I had a fantastic view of the cell but it wasn't as well structured yet as it was to later be. 10km north of Jerilderie I obtained a much better look at the cell, towards Urana. The storm was becoming more organised with a great curved inflow band and rotation evident to the naked eye. The radar image indicates a hook echo (see 0550UTC radar image). Further assistance with footage and radar & discussion with Sydney BOM have confirmed this as a left-mover.

Video: 10km from Jerilderee shows inflow band.

Video: Funnel develops on NW flank, short lived.

Video: Driving towards cell as it moves away into an area with poor road access, this is where I had to leave the storm and it was getting dark, hence poor quality however the overall rotational structure & wall cloud still quite evident.

From here I had a terrific view of the curved inflow bands as seen above. Look at the wall cloud in the 2nd image below, with possible funnel but unable to confirm from this distance.

1830hrs: It's sunset in Wagga and I am beginning to realise that I am probably too far south and too far west to see much of an electrical display tonight. Upon driving into Wagga I do stop to take this sunset photograph:

So I stop and eat some cold Macca's from earlier in the day and grab a coffee from a roadhouse. This is the point where important decisions are made (i.e. where to now!). I was considering driving down to Albury and staying about the North Central/Riverina area until the following day or driving much further north overnight. I decided to do neither as I was very weary and didn't think it safe to drive a long way further so I fired up the laptop to look at the radar and noticed a smallish cell to my NW moving towards Junee between Coolamon and Temora, so with trusty compass in hand drove to Coolamon and found a nice little back country road to watch the lightning display, here's a couple of the shots:

Some time after midnight I was really bushed so I headed back to Wagga and eventually found a safe, quiet suburban street, parked the car and went to sleep until 0500hrs Thursday 16th. A check of the radar and a look at some charts, I decided the best plan was to head back home to start thinking about the next possible chase (Saturday 18th & Sunday 19th October)!

Overall 1550 kms covered and I thoroughly enjoyed it, especially the chili meat pies from the Tocumwal bakery! I was also very pleased to nail my first Supercells on a chase. Next time the video quality and my own positioning will be much better!