It’s Autumn’s million dollar question: when do the fall colors peak in the Sky Islands of southern Arizona?
Here’s what climatology tells us. For those who can’t wait to do some leaf-peeping, head to the White Mountains. Colors climax in early to mid October. Closer to Tucson, Mount Lemmon sees the peak of Fall colors mid to late October. Foliage typically fades after Halloween.
November colors are usually confined to the Huachuca Mountains outside of Sierra Vista, including Ramsey Canyon.
Three elements help change the colors in the leaves: chlorophyll, carotenoids and anthocyanins. Chlorophyll gives leaves their green color & is an important piece to the photosynthesis puzzle. Shorter days this time of year shuts down the photosynthesis process & chlorophyll.
This shut-down allows carotenoids to come out in orange and shimmering yellows, like the aspens atop Mount Lemmon. Anthocyanins also join the leaf peeping party, showing up as radiant reds in maples and oaks.