When does Denver need sun protection?

Whenever the UV index is 3 or above. In Denver that is typically from May through September, and any clear spring or fall day UV reaches 3. The EPA Sun Safety action steps apply at the same threshold used worldwide.

Does Denver need sun protection in winter?

Not every day. Midwinter middays in Denver often sit below UV 3, but clear late-winter and early-spring days cross the threshold before summer fully arrives. Check the live index.

Does city shade protect you from UV in Denver?

Only while you stay in it. Buildings cut some sky, but plazas, crossings and glass bounce UV onto uncovered skin. The live index on this page is the open-sky reading. Treat lunch outside as full-sun time whenever it is 3 or above.

UV index in Denver today

The Mile High City gets more UV per unit of sunlight than sea-level cities because of altitude. Denver's sunny climate and outdoor culture mean long exposure windows from spring through fall, with snow glare a winter wildcard.

Live reading · data by Open-Meteo · reference monitoring by ARPANSA

Today and tomorrow in Denver

Peak UV, temperature and conditions for Denver. Tomorrow’s peak is the number to plan around if you’re heading out in the middle of the day.

Weather conditions right now

Cloud and rain cut heat more than they cut UV. A partly cloudy day in Denver can still sit at protection levels. Why you burn on cloudy days.

When Denver needs sun protection

Sun protection is typically needed from April through October in Denver, and on sunny winter days whenever UV reaches 3.

The threshold, per SunSmart and ARPANSA: whenever UV reaches 3 or above, Slip on covering clothing, Slop on SPF 50+ sunscreen, Slap on a hat, Seek shade and Slide on sunglasses. Read the full sun safety guide.

Where the UV adds up in Denver

Long, happy hours outdoors are where exposure quietly accumulates. Local favourites where the five S’s earn their keep:

City Park and Cheesman Park
Red Rocks trails
Cherry Creek Trail
Washington Park loop

The UV scale at a glance

0–2Low
3–5Moderate
6–7High
8–10Very high
11+Extreme

Frequently asked questions

When does Denver need sun protection?: Whenever the UV index is 3 or above. In Denver that is typically from May through September, and any clear spring or fall day UV reaches 3. The EPA Sun Safety action steps apply at the same threshold used worldwide.
Does Denver need sun protection in winter?: Not every day. Midwinter middays in Denver often sit below UV 3, but clear late-winter and early-spring days cross the threshold before summer fully arrives. Check the live index.
Does city shade protect you from UV in Denver?: Only while you stay in it. Buildings cut some sky, but plazas, crossings and glass bounce UV onto uncovered skin. The live index on this page is the open-sky reading. Treat lunch outside as full-sun time whenever it is 3 or above.