A Western Diamondback Rattlesnake sitting outside of its den in late November. Days later, it disappeared into the rock pile to hibernate.
In Maricopa County, ingress to their selected overwintering sites typically concludes by about the second week of November, unlike Spring emergence, which is a longer process of basking and social behavior that puts them on the surface every day for weeks or more, getting to the den itself is typically less active.
Females and young snakes tend to disappear immediately, likely to avoid burning off the moisture and energy stored throughout the year. Males, especially the larger and older individuals, may continue to bask and conduct social dominance behavior for awhile, before again disappearing to stable, hidden conditions.
For homeowners, this means that the locations where they may be found change dramatically in nature. Unlike pass-through rattlesnake encounters from the Fall, a snake found from November through February is a long-term resident. This also means that these situations are also very fixable. The stable environmental conditions offered by something like an unused wood pile, access under an old shed, or other easy thermostable situation, are very useful. Once the snake is relocated, the homeowner should receive the information about the situation needed to solve the real issue.
