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Los Angeles, CA UV Index Today

Modelled for · GMT-7

5.4 Moderate

EPA suggests shade around midday, a hat and sunglasses.

Today's peak is 8.5 (Very High) at about 1pm local time.

When is UV strongest in Los Angeles today?

UV in Los Angeles peaks at 8.5 (Very High) around 1pm local time (GMT-7). It stays at 6 or above — the high band — for 4 hours, roughly 11am to 3pm. UV is 3 or above for 7 hours.

Local time, midnight to midnight. Bar colour is the EPA UV band, never restyled.

Los Angeles today, in numbers

Latitude
34.0°N — 92 of 121 from the north
Today's peak
8.5 (Very High) — 17 of 121 nationally
Peak arrives
1pm local (GMT-7)
At or above 6
4 hours, 11am to 3pm
At or above 3
7 hours, 10am to 5pm

The window from 11am to 3pm is the practical answer for Los Angeles today. Nationally today the spread runs 11.4 in Hilo (20°N) to 1.3 in Fargo (47°N). Why latitude and the clock decide this →

The marine layer decides the peak hour

Two parts of this metro can post very different UV days at the same hour. From late spring into early summer the marine layer pushes inland off the Pacific, and it does not clear everywhere at once. The coastal strip forms cloud first and holds it longest; the San Fernando and San Gabriel Valleys break out earliest. A strong push fills the basin and reaches the inland valleys. A weak one stops a mile or two from the water. Crossing the Sepulveda Pass in June can take you from one regime to the other in ten minutes.

Timing is why that matters. Los Angeles sits east of the 120th meridian that defines Pacific time, so the sun reaches its highest point near 12:53 p.m. on daylight time, give or take the seasonal drift. In the valleys the deck has usually broken by then. Near Venice or Santa Monica it often has not, and the day’s maximum arrives later and lower than the number published for the city as a whole suggests.

The season has local names, May gray and June gloom, and it lands squarely on the weeks when the sun is highest. By late August and September the deck breaks earlier in the day and forms less often, so the coastal strip’s clearest, strongest afternoons tend to arrive well after the solstice rather than on it. Ten miles inland that inversion never applied.

Nearest metros we model

UV changes with latitude, not with a city boundary, so a neighbour a hundred miles north reads differently for a reason.

What does Los Angeles’s UV index mean today?

5.4 is Moderate. EPA suggests shade around midday, a hat and sunglasses. Today Los Angeles also reaches Very High at its peak — a different band from the one it is in right now, which is why the hour matters as much as the day.

The scale is open-ended: 11 is where the named bands stop, not the maximum. All five bands, with the EPA guidance for each →

Modelled, not measured

The UV figures for Los Angeles are computed by the Copernicus atmosphere model, not read off an instrument here — unlike the AQI on our air-quality pages, which comes from a regulatory monitor. Cloud is where a UV model is weakest. What that means in practice →

Questions about UV in Los Angeles

What is the UV index in Los Angeles today?

5.4 right now (Moderate), peaking at 8.5 around 1pm local time. UV stays at 6 or above for 4 hours, from about 11am to 3pm. This is a modelled value, not a ground measurement.

When is UV strongest in Los Angeles today?

Around 1pm local time (GMT-7), not at noon — solar noon drifts across a timezone and daylight saving moves it later on the clock.

Is this measured or modelled?

Modelled. The figures come from the Copernicus atmosphere model via Open-Meteo, unlike the AQI on our air-quality pages, which is read from an EPA regulatory monitor. Cloud cover is where a UV model is weakest.

Updated