Developer Abdullah Almuntassir has shared some previews of environment changes within Ultra Weather v2.6 compared to v2.5 over on the Ultra Weather XP Facebook group.
The screenshots below show the enhanced sky colours that will be released with version 2.6 compared to the same screenshot with version 2.5. The screenshots are taken with the same aircraft at the same altitude at the same time of day. Do bear in mind that this these shots are still a work in progress.
Although we have no timeframe for the update, Abdullah does mention that the update will be free for users of v2 of Ultra Weather XP.
If you don’t currently own Ultra Weather for X-Plane, you can purchase it here at the X-Plane store.