Why autumn this year is more spectacular than usual

This autumn has been quite spectacular here in the southwest. Vibrant colours that I associate with parts of the US. The last time I remember it being so colourful was the autumn of 2003 - after we'd had a hot and dry summer.

The colours we see are always there but are usually masked by the green chlorophyll. It's only in the autumn, when the days are shorter and cooler and the trees stop making clorophyll, that we see them.

The red and purple anthocyanins and yellow and orange carotenoids come to the fore and we see the hidden colours of the leaves.

Apparently, the best conditions for intense leaf color to develop are dry, sunny days followed by cool (but not freezing) nights. This autumn certainly has been dry and not cold. And so that's why this autumn seems more spectacular than usual.