The 47-year-old, identified as Sallie Brady was found on couch in the living room of the home on Talina Court in Ramsey just after 5:45 a.m.
She was taken to Good Samaritan Hospital in Suffern, where she was pronounced dead.
The fire appears to have started in the kitchen possibly from a faulty dishwasher and was apparently simmering for some time, and the cause is under investigation. It is not believed to be suspicious.
Firefighters struggled with the closet hydrant, but still knocked down the flames in 15 minutes.
Firefighters also had trouble finding the house because of the thick fog overnight.
A dog in the house was rescued.
