DermUV
UV Index
Boston, MA
Beach UV Index in Boston, MA
Boston sits at 42 degrees north, so summer UV peaks around 8 to 9, while harbor reflection can push effective exposure noticeably higher. The live UV index for Boston above this page refreshes every minute. During summer, expect peak readings between 10am and 3pm, with values climbing fastest in the hour before solar noon.
Monthly UV Index in Boston
Average UV in Boston 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 Boston is lowest during Jan, Dec.
| Month | Avg UV | Risk |
|---|---|---|
| Jan | 4.0 | Moderate |
| Feb | 5.5 | Moderate |
| Mar | 7.3 | High |
| Apr | 9.2 | Very High |
| May | 10.3 | Very High |
| Jun | 10.7 | Very High |
| Jul | 10.5 | Very High |
| Aug | 9.7 | Very High |
| Sep | 8.1 | Very High |
| Oct | 6.1 | High |
| Nov | 4.4 | Moderate |
| Dec | 3.6 | Moderate |
What the UV Index Numbers Mean For Your Skin
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 Boston, 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.
Sun Protection in Boston, What Dermatologists Recommend
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 Boston-specific point: water and wet sand reflect 15 to 25 percent of UV back up onto your face, so the underside of your jaw and chin burn faster than your shoulders. 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.
Skin Cancer Warning Signs, the ABCDE Rule
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 Boston 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.
UV Index Boston, Frequently Asked Questions
what is the uv index in boston right now
The live UV index for Boston, MA on this page updates every minute from atmospheric model data. During summer, typical Boston 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 boston
UV in Boston 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 boston 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. Boston 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 boston in summer
Yes. Summer UV in Boston 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.
does water reflection raise uv at boston beaches
Yes, significantly. Open water and wet sand reflect 15 to 25 percent of incoming UV back up onto exposed skin, which means your face and the underside of your jaw take a hit even when you are wearing a hat. Beach umbrellas block direct sun but not reflected UV. Reapply sunscreen every 80 minutes when swimming.