I think it would be great if you added a config to this plugin with the option of being able to add/subtract a value from your plugin's atmospheric brightness settings. This would make certain things easier for us with the way the weather works now. For example, I prefer to use timeofday to freeze the date to keep full moon full, while using your plugin for weather. However this also means using timed execute to also adjust the brightness manually depending on in-game time of day. Since this plugin frequently overwrites atmospheric brightness settings (as it should, tbh).... I believe it is now necessary to add two atmospheric brightness modifiers which are applied to any current settings this plugin is using. One for day time and one for night time. 

For example

Atmospheric Brightness Day : 1.5

Atmospheric Brightness Night : 3.0

This would, in theory, add 1.5 brightness to whatever value set by the plugin during the day, and 3.0 brightness value at night.