When does Seattle need sun protection?

Whenever the UV index is 3 or above. In Seattle that is typically from May through September, and any clear spring or fall day UV reaches 3. The EPA Sun Safety action steps apply at the same threshold used worldwide.

Does Seattle need sun protection in winter?

Not every day. Midwinter middays in Seattle 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 the water make UV worse in Seattle?

It can. Sand and water reflect ultraviolet, so skin that is not covered (including under the chin and on the tops of feet) picks up extra dose on top of the direct sun. The live UV index on this page is the sky reading; reflection is on top of that.

UV index in Seattle today

Seattle's reputation for grey skies makes it easy to skip sunscreen, but clear summer days push the UV index well above the protection threshold. Alpine day trips and snow reflection add extra dose on top of the city reading.

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

Today and tomorrow in Seattle

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

When Seattle needs sun protection

Sun protection is typically needed from May through September in Seattle, with late-spring and early-fall clear days crossing UV 3 before summer fully arrives.

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 Seattle

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

Discovery Park bluff trails
Alki Beach
Gas Works Park
Lake Washington boulevard rides

The UV scale at a glance

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

Local support in Washington

Cancer Council WA: West Australian sun-safety campaigns and SunSmart schools.

Frequently asked questions

When does Seattle need sun protection?: Whenever the UV index is 3 or above. In Seattle that is typically from May through September, and any clear spring or fall day UV reaches 3. The EPA Sun Safety action steps apply at the same threshold used worldwide.
Does Seattle need sun protection in winter?: Not every day. Midwinter middays in Seattle 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 the water make UV worse in Seattle?: It can. Sand and water reflect ultraviolet, so skin that is not covered (including under the chin and on the tops of feet) picks up extra dose on top of the direct sun. The live UV index on this page is the sky reading; reflection is on top of that.