The shockwave hit at about 10am this morning. I find the IPS magnetometer plots a very good guide to whether an aurora is worth looking for (in Canberra, at least)
http://www.ips.gov.au/Geophysical/1/1
Another very useful indicator used to be high frequency flutter on the audio for the BBC's shortwave transmissions (from London) on 15.070 mHz. The short path takes it to high southern latitudes on its way to Oz, and auroral activity modulates the signal in an easily identifieable way. Not sure if the BBC still uses that frequency, but any 19 metre band transmission from London should work.
DN