It could just be a run of bad luck. I always have to edit All Natural's .ini, as the default length of any given weather is quite long (8 or 10 hours, I think?). This seems like it takes
forever, especially if you have slowed down the in-game time speed. Occasionally the weather will just switch between stormy and rainy, giving you crappy weather for several days. The chance of poor weather also increases depending on where you are. Leyawiin, for example gets a lot of rain.
Here is what I have in my .ini, it seems to work pretty well:
set ANVars.ClearLength to 12 ; Average duration of a clear weather. (12) set ANVars.CloudyLength to 7 ; Average duration of a cloudy weather. (7) set ANVars.OvercastLength to 5 ; Average duration of a overcast weather. (7) set ANVars.FogLength to 2 ; Average duration of a foggy weather. (7) set ANVars.RainLength to 4 ; Average duration of a rainy weather. (5) set ANVars.StormLength to 2 ; Average duration of a stormy weather. (5) set ANVars.SnowLength to 9 ; Average duration of a snowy weather. (9)
Edit: ok so the average length isn't quite as bad as I remembered, but it sure feels like it after a couple of bad days.
And really, have you ever seen a fog that lasted 7 hours in the middle of a forest?