Actually, in my experience, it is most prominent in early spring during cool but warming temps. In hot summer temps, especially when accompanied by occasional rain showers, the algae becomes much less of a probelm. In winter it is not visible.
By the way, what you are seeing is actually the last life stages of the algae. It starts on your pond bottom...look closely in water 1 to 3 feet deep and you should see it forming. At some point, it releases its attachment to the bottom and becomes the floating mats of scum that everyone abhors. It actually does a service, as do most things in nature...it utilizes nutrients from the water. It is harmless but not pleasant to look at or throw a fishing line over. It does provide cover for fish, on the positive side. I hope I have helped.
