Another tree that's flowering now and also does well on the Front Range is the Canada Red Flowering Cherry (Prunus virginiana 'Schubert') , aka chokecherry.
My tree does not appear to produce fruit every year but when it does, the berries become a territorial bird feast. A robin will often watch the tree from a distance and immediately swoop down to chase away any visiting birds. In a matter of a few weeks, the tree is picked dry.
More info on the Canada Red.