Does Lake Berryessa need sun protection in winter?

Not every day. Midwinter middays in Lake Berryessa 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 Lake Berryessa?

It can. The lake surface 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 Lake Berryessa today

Lakeside Lake Berryessa (CA) is 38.6° south. Time on the water or the foreshore adds reflection on top of a January sky that commonly reaches 8–10 (very high). This is cool-temperate America: 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 Lake Berryessa

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

When Lake Berryessa needs sun protection

Sun protection is needed in Lake Berryessa typically from May through September, and any clear spring or fall day UV reaches 3. Lake glare adds a second dose on top of the sky reading, the same way a beach does.

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 Lake Berryessa need sun protection?: Whenever the UV index is 3 or above. In Lake Berryessa 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 Lake Berryessa need sun protection in winter?: Not every day. Midwinter middays in Lake Berryessa 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 Lake Berryessa?: It can. The lake surface 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.