Here's another sky type I have been working on:

Heavy Dark Rain Clouds

I don't think the recce/obs types will like this one very much! Fortunately, you will only see this cloud type on rainy days.

I think I am almost finished tinkering with the new types. When I am finished, it looks like I will be adding approximately 10 new skies, which will provide an even greater variety of cloud conditions to fly in. The update will also have a few minor revisions to a few of the existing cloud types in the current mod. I also recently discovered a setting which controls some of the fog or haze on the horizon, and I will be interested in tinkering around with that setting, as well.

Edit: Can anyone tell me why my picture appears so large and doesn't show an attachment at the bottom of the post? I copied the link to the pic from Photobucket, but obviously I am not doing it right.