Julian is popular year-round but has two distinct high seasons. Autumn (September to November) is apple season — orchards are open for picking, the bakeries are at full capacity, and the mountain landscape turns gold and orange. This is when Julian is busiest; weekends in October can be very crowded, and parking becomes difficult. Go early or on a weekday.
Spring is quieter and equally beautiful — wildflowers bloom in the meadows and the days are warm without the summer heat. Summer is pleasant in the mountains when San Diego is baking, with temperatures typically around 25°C. Snow falls occasionally in winter, which sends crowds of Californians up to see it; the town can be unexpectedly busy after a snowfall.