We had a bit of a discussion about this on the now defunct Australian Ethnobotany last year.

It seems like it's happening again. Roadside Acacias (unidentified, they're like weeds over here) seem to be flowering profusely again quite early.

Last year at AE it was speculated that the species in general has a genetic memory (not in those specific words, I'm paraphrasing) and that Acacias just seem to know when an unusually hot dry season is approaching and flower early as some sort of adaptation. Some speculated that it could be an indicator of extraordinary upcoming fire season. Given the affinity Acacia seeds have with fire and heat it is certainly plausible.

It also seems to be a very plausible theory as Australia is an ancient land with many species that have adapted to fire & reproduced successfully with fire for eons.

Last year (2012) the observations did indeed prove to be correct and we had a severe fire season where bushfires wreaked havoc all around the country. Several days during mid/late summer I recorded temps over 48 deg celcius in my own back yard and one day the mercury hit 50 with less than 5 % RH.

I hope I'm wrong, let's hope it's just a seasonal flash in the pan so to speak.