Express installed via npm global, but cmdlet not found

Following Azure's node.js tutorial at this url: http://www.windowsazure.com/en-us/documentation/articles/web-sites-nodejs-store-data-mongodb/

I am unable to run 'express' after installing it, given the following error:

The term 'express' is not recognized as the name of a cmdlet, function, script file, or operable program.

I can see that express successfully installed to %APPDATA%\Roaming\npm\node_modules\express

The only solution I know of to this problem is manually adding this directory to the PATH variable, which is undesirably inconvenient and not mentioned in the tutorial.