Add a tackifier to the seed and mulch you're going to use this spring...
this is typically how the hydroseeders keep stuff on slopes.
http://www.agry.purdue.edu/turf/pubs/agry-99.05.htm

Cool season grasses like red fescue, tall fescue, kentucky bluegrass
need cool soil temperatures for a fairly prolonged period of time to
germinate and establish well. Get that seed down as soon as practical.

Kay