Go look outside (but be sure to come back). If you can see sky, it's probably a rich, deep blue. Unless you pay attention to the sky all year, you may not realize just how blue the sky can be during the Fall. In the summer, we tend to spend more time outside, and because of that, cameras stay busy. But if you watch the summer sky, you'll notice that the sky can often be grey, or a pale blue. Deep blue skys are much more appealing than the grey ones, especially in photos.
The culprit is humidity. Autumn tends to bring cooler temperatures and lower humidity (especially for southern states). When there's less moisture in the air, the blue color of the sky is intensified. If you want the richest color, be sure to use a polarizing filter. It will help saturate the color of the sky, making your photos even stronger.
So, keep your camera handy during the Fall events with your congregation... this deep blue sky won't last forever.
Want to learn more? Check out this article.