It might be possible that a fix for this is already in the works (unless if this was intentional, in which case this wouldn't be considered an issue), since this is a fairly noticeable difference compared to the previous 2.7.1 beta, but I've seen this to be the case with both player-summoned storms and naturally occurring ones in the recent 2.7.2 beta. In the 2.7.1 beta the sky got noticeably darker, even more so than in the previous versions for 1.7.10 - 1.12.2 which is something I really like. I also like that the light level dropped a bit too the closer you got to a storm in 2.7.1, just like how the light level drops during vanilla thunderstorms.

However, in the 2.7.2 beta the dimming of the sky and the slight dimming of the lighting doesn't seem to happen anymore near storms, or at least not to the extent it did in 2.7.1. The sky does seem to change a little bit, but even when right by a tornado, it's still pretty much blue while the sun remains quite visible. I experienced this on Forge 40.2.0, as well as on the latest CoroUtil, and temporarily removed all other mods and disabled any resource packs I had for the purposes of testing the difference in an unaltered setting where coroutil and weather2 are also the only mods installed, which I guess could be useful info. Here are some screenshots for comparison:

Here's what the sky looks like under a storm in the recent 2.7.2 beta:

And here's what the sky looks like under a storm in the previous 2.7.1 beta (slightly unrelated, but yes, this is a different world):

As you can see, there's a clear difference. Once again, I don't know if this was intentional or not, but in case it isn't, I hope what I typed here was helpful, since I'm completely new to GitHub and proper issue reporting. If this wasn't helpful, I'd appreciate to hear what I have to do and what I could improve on in order to do this properly.

Confirmed. 2.7.2 doesn't even work on server-side either, so I'd stay on 2.7.1 for now.

This is also an issue on the new 2.7.4 version apparently. Seems like this was intentional or they just aren't aware of it.

Yes, this was intentional. See 0b20cf1 . Though it does feel a little too light, as I commented in my issue.

I opened pull request #522 , here's hoping Coro sees it!

Though it does feel a little too light, as I commented in my issue.

i agree it does look too light