I had an issue when creating Named Credentials. When I named it "IBM Cloud Weather", it threw an error saying that it couldn't find "IBM Bluemix Weather" named credential. 
So I edited and renamed the Named Credential to "IBM Bluemix Weather". THEN it tells me it could't find "IBM Cloud Weather" named credential. 

So to fix it, I had to have both named credentials created, then it worked fine. Anyone else have this problem?