It is raining.
I can hear the hypnotic splattering of drops on leaves and in puddles.
It is making patterns in the Thames, patterns that slowly change. Remember mixing oil based paint and water, twirling the mixture round and then placing paper on top to capture the abstract image?
It is like that, but born of river water, wind, rain, current, tides, gusts and vortices caused by buildings and the subtle changes in rain rates.
I can't take a picture as it's too faint and the camera vibrates just that little too much, but I suddenly realised what it reminded me of - the planet Solaris (above).
Must be time to sleep and dream......