Cloud cover can make or break many kinds of outdoor photographic opportunities and that’s why the website Clear Dark Sky should be bookmarked by any discerning photographer. This website, originally intended for astronomers, will give you a cloud cover forecast for a specific time and location. Whilst most people will immediately imagine using this to predict clear skies at night for astrophotography, there’s no reason why you can’t also use it to predict days of overcast conditions which are often preferred for wildlife and macro photography.
As you can see from the screenshot, the simple charts manage to pack in a lot of useful information including the level of cloud cover, the transparency of that cloud cover, and even the wind speed. If there’s a gale-force wind blowing, it’s going to make steady long exposures at night tricky, so I do appreciate the added weather info on top of the cloud predictions. The darkness indication is also of particular importance to photographers because this takes into account the phase of the moon and the position of it above the horizon. For good astrophotography you want to have the darkest sky possible. This usually means shooting at a time of the month when the phase of the moon is very small, and at a time when it has yet to rise, or has already set. The darkness forecast takes this into account to give you some indication as to when the darkest part of the night will be. Hopefully it coincides with a clear cloud forecast!
BONUS: You can even sign up for alerts using this URL, to be notified whenever there’s going to be a clear sky at night. If astrophotography is your thing, this is pretty awesome! You might also want to consider the Northern Lights alert emails from AuroraWatch.ca. I use this one, and I know a lot of others do as well!