Solar astronomy has a lot to do with outdoor photography whether it's landscape or portraiture, or any other type of photography. If the Sun's shining in a particular way, you need to adjust your settings to accommodate it. Knowing ahead of time can help a little with that. So the first two images show how clear/cloudy the sunrise and sunset will be today.
Another important aspect of solar astronomy for photography is the expected strength of the aurora borealis or the northern lights. (I live in the northern hemisphere so apologies to those under southern skies and the aurora australis.) There are 5 websites brought in below that show most of the information about the aurora, at least enough to get you ready for a late night!
Better sunrises and sunsets are shown by warmer colors. Reds are best, dark blues mean pretty solid cloud cover.
Aurora Borealis Information
Visualization of current aurora:
NOAA SWPC Space Weather Overview
Planetary K Index