Tombstone sits at 4,540 feet elevation in the Sonoran Desert, which moderates what would otherwise be brutal Arizona heat. Summers (June–August) are warm rather than scorching, with temperatures in the upper 80s to low 90s Fahrenheit, and afternoon monsoon storms roll through from July onward — dramatic but usually brief. Winters are mild and sunny, with occasional cold nights but rarely freezing.
The best times to visit are spring (March–May) and fall (September–November), when temperatures are ideal — typically 65–80°F during the day — and the crowds are manageable. Avoid major holiday weekends and Helldorado Days (usually held in October), when the town becomes very crowded and accommodation prices jump.
Helldorado Days itself is worth knowing about: Tombstone's major annual festival, running since 1929, fills the streets with reenactors, parades, and period events over three days in mid-October. If you enjoy that kind of thing, it is an excellent time to visit; if you prefer the town quieter, avoid it. The annual Wyatt Earp Days in late May draws a smaller but enthusiastic crowd of history buffs.
For the most atmospheric visit, arrive early on a weekday morning. The reenactments don't start until mid-morning, and the few minutes when Allen Street is empty and the light is coming over the Dragoon Mountains to the east are the best Tombstone has to offer.