DermUV
UV Index
Chicago, IL
Today's UV Index for Chicago
Chicago is currently in summer. Chicago sits on Lake Michigan, where summer water reflection adds roughly 10 percent to UV exposure for anyone at the lakefront. This page tracks the live UV index, hourly forecast, and Fitzpatrick-skin-type burn time, refreshed every minute from atmospheric model data.
Seasonal UV Patterns in Chicago
Average UV in Chicago 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 Chicago is lowest during Jan, Dec.
| Month | Avg UV | Risk |
|---|---|---|
| Jan | 4.1 | Moderate |
| Feb | 5.6 | Moderate |
| Mar | 7.4 | High |
| Apr | 9.2 | Very High |
| May | 10.3 | Very High |
| Jun | 10.7 | Very High |
| Jul | 10.6 | Very High |
| Aug | 9.8 | Very High |
| Sep | 8.2 | Very High |
| Oct | 6.2 | High |
| Nov | 4.5 | Moderate |
| Dec | 3.7 | Moderate |
How UV Index Numbers Map to Burn Risk
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 Chicago, the reading sits around 11, which puts everyone outside the very high 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.
Sunscreen & Sun Safety in Chicago
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 Chicago-specific point: haze and high humidity in summer feel cooling but filter very little UV, which is why people get burned on overcast days. 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.
Early Skin Cancer Detection, the ABCDE Method
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 Chicago 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.
Common Questions About UV in Chicago
what is the uv index in chicago right now
The live UV index for Chicago, IL on this page updates every minute from atmospheric model data. During summer, typical Chicago UV runs between 3 and 11. 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 chicago
UV in Chicago 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 chicago 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. Chicago 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 chicago in summer
Yes. Summer UV in Chicago reaches around 11 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.
is winter sun in chicago actually dangerous
It can be. Fresh snow reflects up to 80 percent of UV back onto your face, and that reflection happens at low sun angles your skin is not used to. Skiers and dog walkers often get burned on bright January days when the air feels freezing. The UV index might read 2 but effective exposure can match a summer afternoon.