Thanks for the prayers everyone! I talked to my parents again last night, and they are fine. Although the fire is not yet fully contained, they are starting to get a handle on it, and hopefully will be able to keep it from spreading towards town any more. One helpful factor is that the Prescott airport is a major staging area for the Forest Service firefighting crews in the region, so there was a lot of equipment readily available. My father even gets a couple days off work, since the school he teaches at is being used as an evacuation shelter.
Prescott Daily Courier coverage
Fire near Prescott being held at bay (Arizona Republic)