Massachusetts, United States · 42.36, -71.06
Today's peak is very high. Skin damage happens fast: roughly 19 min before burning at the worst hour. Avoid direct sun entirely inside the danger window below.
About the UV index in Boston
Boston sits at 42.4° N, in the northern hemisphere. Today's UV peaks at 9: the "very high" band, which uvlevel.net treats as serious danger for unprotected skin at the worst hour.
Boston sees the widest UV swing of the year of any latitude band: a sharp summer peak around June and July, and a winter trough around December and January where midday UV can sit near zero for weeks at a time.
Hour by hour today
| Local time | UV index | Risk |
|---|---|---|
| 00:00 | 0 | No danger |
| 01:00 | 0 | No danger |
| 02:00 | 0 | No danger |
| 03:00 | 0 | No danger |
| 04:00 | 0 | No danger |
| 05:00 | 0 | No danger |
| 06:00 | 0.5 | No danger |
| 07:00 | 1.6 | No danger |
| 08:00 | 3.4 | Caution |
| 09:00 | 5.4 | Caution |
| 10:00 | 7.2 | Danger |
| 11:00 | 8.5 | Serious danger |
| 12:00 | 9 | Serious danger |
| 13:00 | 8.5 | Serious danger |
| 14:00 | 7.2 | Danger |
| 15:00 | 5.4 | Caution |
| 16:00 | 3.4 | Caution |
| 17:00 | 1.6 | No danger |
| 18:00 | 0.7 | No danger |
| 19:00 | 0.2 | No danger |
| 20:00 | 0 | No danger |
| 21:00 | 0 | No danger |
| 22:00 | 0 | No danger |
| 23:00 | 0 | No danger |
| Skin type | Time to burn |
|---|---|
| I · always burns, never tans | 15 min |
| II · burns easily | 19 min |
| III · burns sometimes | 26 min |
| IV · rarely burns | 33 min |
| V · brown skin | 44 min |
| VI · deeply pigmented | 1 h 14 min |
Next 7 days · daily peak
Frequently asked
Is the UV index dangerous in Boston today?
Yes. UV in Boston is forecast to reach 3 or higher from 07:46 to 16:13 local time today, peaking at 9 (estimated from solar position, live forecast data was unavailable).
What time is UV highest in Boston?
UV is highest in Boston at around 12:00 local time today, reaching 9 (estimated from solar position, live forecast data was unavailable).
How long can unprotected skin stay out in Boston today?
At today's peak of 9, fair skin (Fitzpatrick type II) with no sunscreen burns in about 19 min (estimated from solar position, live forecast data was unavailable). Darker skin types take longer. See the table above for every type.
Does the UV index in Boston change with the seasons?
Boston sees the widest UV swing of the year of any latitude band: a sharp summer peak around June and July, and a winter trough around December and January where midday UV can sit near zero for weeks at a time.
Nearby cities
Forecasts and elevation from Open-Meteo. The second UV opinion contains modified Copernicus Atmosphere Monitoring Service (CAMS) information; neither the European Commission nor ECMWF is responsible for how it is used here.
uvlevel.net gives general sun-safety guidance, not medical advice. Photosensitising medication, skin conditions, infants and a history of skin cancer all call for stricter limits than shown here.