Only point of feedback I have for you is that the clouds look a little bit off. I personally think it has to do with the color. Often there's some blue to be seen in the darker parts of heavy clouds.
Kind of like these images:
On this image there is a tiny spot in the left upper corner where you can see the color of the sky behind the clouds, and you can see that it's quite close to the dark grey-ish blue in the cloud's shadows.
The shadows here are a tad more purple looking, but there's still a sort of unity between those shades and the sky's color.
Don't get me wrong; your clouds are certainly not bad, not at all. I think the cloud's shading in the upper right corner of your piece is extremely well done, but it's just that the rest looks like it just might be a bit too yellow.
This is photo i've made last year. Then i thought that this is very good practicing photo for using in pastel landscape painting (I realy love that "Lonely Tree").
So the sky on that Photo almost all of it covered by some big spot of clouds and because of that i didn't really knew how to paint it. It was hard task for me. But I still wanted that the main focus would be on the foreground tree. Maybe because of that i didn't worked enough on the sky.
I'll try to add some Blue\Purple color to the cloud mess.