UV index in St John today
St John in England sits inland at 50.4°N, where dry air and fewer clouds often mean harsher UV than the temperature suggests. Summer middays typically reach 8–10 (very high). This is cool-temperate Britain: 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 St John
Peak UV, temperature and conditions for St John. 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 St John can still sit at protection levels. Why you burn on cloudy days.
When St John needs sun protection
Sun protection is needed in St John 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 St John need sun protection?
- Whenever the UV index is 3 or above. In St John that is typically from May through September, and any clear spring or fall day UV reaches 3. The UK Health Security Agency and WHO use the same UV Index scale worldwide.
- Does St John need sun protection in winter?
- Not every day. Midwinter middays in St John 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 St John?
- Yes. UV is not heat. A cool, windy or lightly cloudy day in St John 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.