Strange colour in sky ?

Hadn't realised it was to be so nice today and missed any chance of sun rising type photos. Set out later for a dog walk with camera and tripod and quite happy with some of the shots. Tried a circular polarising filter but still getting to grips with it (aka don't know what I'm doing !). Got some nice ones with Ben Lomond but it features all the time, dominating the landscape here as it does. Hence my photo for today is a gentler one, looking over Balloch to the Campsie Fells