Not much info for us to work with, like oil vs. gas, etc. First thing to check is your plain old circuit breakers or fusebox, to see if it tripped. The only thing I would try - if it is an OIL furnace, is to press the reset button on the burner unit. It might have been tripped by the power outage. This might just fix it. If it comes back on and then later keeps tripping off, then don't keep pressing this button as it can really muck things up. Have you had your annual furnace inspection/cleaning maintenance yet? This could be a good time to do it.