A great time to fish at Deer Lake is when the temperature cools down, overcast skies, and the water is a little choppy from a light breeze. Light rain doesn't hurt fishing either.
I've caught the most fish at Deer Lake when during windy days, but I'm not talking about heavy winds, just enough to cause some ripples in the water.
When there's no wind at Deer Lake, the water colour tends to be blackish. Dead. With wind, the water colour tends to be lighter. As if, the life forms are moving, and as a result, fish tend to be more active, more willing to chase lures.