UV index in Fort Lyon today

Inland Fort Lyon (CO) is 38.1° south. Without sea haze, January UV commonly runs 8–10 (very high), and a cool morning is no reason to skip sunscreen. This is cool-temperate America: summer UV still climbs into the very high band, and spring arrives before the weather feels hot.

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

Today and tomorrow in Fort Lyon

Peak UV, temperature and conditions for Fort Lyon. 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 Fort Lyon can still sit at protection levels. Why you burn on cloudy days.

When Fort Lyon needs sun protection

Sun protection is needed in Fort Lyon typically from May through September, and any clear spring or fall day UV reaches 3. Inland heat or a cool change does not change the UV index; go by the number, not how the day feels.

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.

The UV scale at a glance

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

Frequently asked questions

When does Fort Lyon need sun protection?
Whenever the UV index is 3 or above. In Fort Lyon 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 Fort Lyon need sun protection in winter?
Not every day. Midwinter middays in Fort Lyon often sit below UV 3, but clear late-winter and early-spring days cross the threshold before summer fully arrives. Check the live index.
Can you burn on a cool day in Fort Lyon?
Yes. UV is not heat. A cool, windy or lightly cloudy day in Fort Lyon can still sit at UV 3 or above, especially from spring through autumn. Temperature on this page is for context only; the UV number is what decides protection.

Live UV nearby