Samsung Galaxy S8 weather app widget is available for download courtesy of xda developers. It is made around material design so looks very elegant with plane and modern wallpapers. There are two ways to install it, first is using own your android’s custom recovery.
For that, download the file from here and put it on the root of your phone’s storage. Boot into recovery and browse for the file that you downloaded earlier. Flash it and reboot.
You will find it in the widget’s section. For some strange reason, S8 weather app widget works only with Samsung’s own touchwiz UI. We tried using it with Nova and it did not work. The earlier weather widget from touchwiz did work with nova. After doing this update it disappear from the widget selection while using nova.
There is another way to install it. Open the zip and search for the 2 apps in the zip file and install.
We have only tried the first method which worked on our non rooted stock s7 edge with nougat and Galaxy S8 home launcher. I just updated the apps and working perfectly. There is no need to root or have custom recovery installed.
It also said to be not working with AOSP ROMs. If it does not, simply uninstall it.