Updating Ember-CLI fails

I'm trying to update ember-cli (and then ember in my projects) following these instructions: http://ift.tt/1ysP6WQ
and
http://ift.tt/1nQpekV

which tells me to do:

npm uninstall -g ember-cli
npm cache clean
bower cache clean
npm install -g ember-cli@2.5.0

This is finishing without errors. I just got a warning:

npm WARN deprecated lodash-node@2.4.1: This package has been discontinued...
npm WARN deprecated graceful-fs@3.0.8: graceful-fs v3.0.0 and before will 0.0 as soon as...

When I then do a

ember -v

afterwards I still get

version: 1.13.7
node: 4.2.1
npm: 2.13.3
os: win32 x64 // win10

Any suggestions why I cant get ember-cli updated?