DermUV
UV Index
Fort Collins, CO
Fort Collins UV Index, Live High-Altitude Readings
Live UV for Fort Collins is shown above and updates each minute. Fort Collins sits at 40.6 degrees latitude, with strong seasonal UV swings between very low winters and high summer peaks. The city is currently in summer, when local UV typically reaches the very high band at noon.
Fort Collins UV by Month
Average UV in Fort Collins peaks during May, Jun, Jul, when high sun angles combine with longer days. The deceptive months are usually early spring and early fall, when air temperatures stay mild but UV climbs into the high category by mid-morning. Locals often skip sunscreen on cool, overcast days, which is exactly when UV-A continues to drive long-term skin damage. UV in Fort Collins is lowest during Jan, Dec.
| Month | Avg UV | Risk |
|---|---|---|
| Jan | 4.9 | Moderate |
| Feb | 6.5 | High |
| Mar | 8.5 | Very High |
| Apr | 10.5 | Very High |
| May | 11.7 | Extreme |
| Jun | 12.2 | Extreme |
| Jul | 12.0 | Extreme |
| Aug | 11.1 | Extreme |
| Sep | 9.4 | Very High |
| Oct | 7.2 | High |
| Nov | 5.3 | Moderate |
| Dec | 4.4 | Moderate |
Reading the UV Index, From 1 to 11+
The UV index runs from 1 to 11 and above. A reading of 1 to 2 is low and most people need no protection. From 3 to 5 you should cover up or use SPF. Anything above 6 is high or extreme, which means unprotected fair skin can begin reddening in well under 30 minutes. On a typical summer afternoon in Fort Collins, the reading sits around 12, which puts everyone outside the extreme risk band. Your skin type matters too: your skin type determines how quickly you burn at any given UV. Kids playing outside for an hour at UV 6 with a hat and SPF 30 are well protected, so this is manageable with simple habits.
SPF Guidance for Fort Collins Residents
At UV 3 to 5, SPF 15 broad-spectrum is the baseline. At UV 6 to 7, move to SPF 30. From 8 upward, SPF 30 plus a hat and sunglasses become the standard combination, with SPF 50 for extended outdoor time. One Fort Collins-specific point: thinner air at this elevation delivers more UV than the index alone suggests, so add one full SPF level above what feels intuitive. Reapply every two hours of direct sun and after swimming. One counterintuitive fact: car and home windows block UV-B but most pass UV-A, which still ages skin and contributes to skin cancer risk. Source: American Academy of Dermatology.
ABCDE: How to Check a Mole at Home
The ABCDE rule is the simplest way to check a mole at home. Asymmetry: one half does not match the other. Border: irregular or fuzzy edges. Color: more than one shade. Diameter: larger than 6mm, about the size of a pencil eraser. Evolving: any recent change in size, shape, or feel. Tracking daily UV in Fort Collins matters because skin damage is cumulative, and one bad burn in childhood roughly doubles lifetime melanoma risk. This information is educational only and not a substitute for medical advice. Consult a board-certified dermatologist for personal skin health guidance.
Fort Collins UV FAQ
what is the uv index in fort collins right now
The live UV index for Fort Collins, CO on this page updates every minute from atmospheric model data. During summer, typical Fort Collins UV runs between 3 and 12. The number above this page reflects current cloud cover, time of day, and sun angle. Refresh once or twice if you just stepped outside.
what time of day is uv highest in fort collins
UV in Fort Collins peaks between roughly 11am and 2pm local time, with the absolute maximum near solar noon. In summer, that window shifts slightly because the sun rises and sets at different times. Cloud cover can shave a few points off the peak but rarely flattens it. Plan high-effort outdoor activity for before 10am or after 3pm if you want to keep exposure low.
do i need sunscreen in fort collins today
If the live UV index above this page reads 3 or higher, yes. Below 3, daily SPF 15 is still recommended by the American Academy of Dermatology for routine exposure. Fort Collins sees May, Jun, Jul as its highest UV stretch, when SPF 30 broad-spectrum is the minimum most dermatologists suggest. Cloudy days still let through 80 percent of UV-A, which drives long-term aging.
is uv dangerous in fort collins in summer
Yes. Summer UV in Fort Collins reaches around 12 at its peak, well into the very high or extreme category on the WHO scale. Unprotected fair skin can begin reddening in 15 to 25 minutes at that level. Sunglasses, SPF 30 or higher, and a wide-brim hat are the standard combination.
does altitude make uv worse in fort collins
Yes. Fort Collins sits at about 5003 feet, and UV increases by roughly 8 to 10 percent for every 1,000 meters of elevation. At Fort Collins's altitude that adds roughly 14 percent on top of whatever the index reads. Cold air and snow can hide this entirely. Wear sunscreen on cloudy winter days too.