|A particularly useful site that gives a real-time graph of geomagnetic activity as seen from the UK is
http://www.dcs.lancs.ac.uk/iono/aurorawatch/. The site will also send a email or text message in the event of major activity.
For southern hemisphere information look at
The site www.spaceweather.com is an excellent source of information on the state of solar activity and also gives warnings about other astronomical events.