I now live in Dallas, TX, USA and we have almost nothing but pink/purple lightning with our storms. The local meteorologists say it has mostly to do with the high concentration of pollen that blows in from the Rocky Mtns and across the plains and our pollution levels. Growing up in the Tennessee rurals I only ever remember blue. This time of year we get supercells about once every 10-12 days and even as I type this there is a storm approaching off to the west and it is bright pink fork and dark purple sheet.
