When does Ottawa need sun protection?

Whenever the UV index is 3 or above. In Ottawa that is typically from May through September, and any clear spring or fall day UV reaches 3. Health authorities use the same UV Index threshold worldwide.

Does Ottawa need sun protection in winter?

Not every day. Midwinter middays in Ottawa often sit below UV 3, but clear late-winter and early-spring days cross the threshold before summer fully arrives. Check the live index.

Does city shade protect you from UV in Ottawa?

Only while you stay in it. Buildings cut some sky, but plazas, crossings and glass bounce UV onto uncovered skin. The live index on this page is the open-sky reading. Treat lunch outside as full-sun time whenever it is 3 or above.

UV index in Ottawa today

Ottawa's riverside paths and Rideau Canal corridor see strong summer UV on clear days. Reflective water and open greenspace add dose on top of the sky reading.

Live reading · data by Open-Meteo · reference monitoring by ARPANSA

Today and tomorrow in Ottawa

Peak UV, temperature and conditions for Ottawa. 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 Ottawa can still sit at protection levels. Why you burn on cloudy days.

When Ottawa needs sun protection

Sun protection is typically needed from April through September in Ottawa, and on any clear day the UV index reaches 3.

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.

Where the UV adds up in Ottawa

Long, happy hours outdoors are where exposure quietly accumulates. Local favourites where the five S’s earn their keep:

Rideau Canal paths
Gatineau Park trails
Major's Hill Park
Dow's Lake

The UV scale at a glance

0–2Low
3–5Moderate
6–7High
8–10Very high
11+Extreme

Frequently asked questions

When does Ottawa need sun protection?: Whenever the UV index is 3 or above. In Ottawa that is typically from May through September, and any clear spring or fall day UV reaches 3. Health authorities use the same UV Index threshold worldwide.
Does Ottawa need sun protection in winter?: Not every day. Midwinter middays in Ottawa often sit below UV 3, but clear late-winter and early-spring days cross the threshold before summer fully arrives. Check the live index.
Does city shade protect you from UV in Ottawa?: Only while you stay in it. Buildings cut some sky, but plazas, crossings and glass bounce UV onto uncovered skin. The live index on this page is the open-sky reading. Treat lunch outside as full-sun time whenever it is 3 or above.