Searching Google for \'Qt5 - Windows 10 - VS 2015\' only brought up a blog post from April stating that support for VS 2015 is in the works (link).
The Qt5 downloads
I just wrote a small article explaining how to compile Qt 5.5.1 (with QtWebkit) with Visual Studio 2015.
I realize this is by no mean a good answer: while it does the job, that article mostly relies on helper Windows batch files you can download from my site. As a consequence, while I don't plan to pull my site or the article itself, other SO users or admins would be in their right to flag this answer as too volatile...
Anyways, until Qt folks offer official pre-built binaries built with Visual Studio 2015, I believe my article saves the day. Hope that helps.