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Oakland, CA UV Index Today

Modelled for · GMT-7

What is the UV index in Oakland right now?

4.7 Moderate

EPA suggests shade around midday, a hat and sunglasses.

Today's peak is 6.7 (High) at about 1pm local time.

When is UV strongest in Oakland today?

UV in Oakland peaks at 6.7 (High) around 1pm local time (GMT-7). It stays at 6 or above — the high band — for 3 hours, roughly 12pm to 3pm. UV is 3 or above for 6 hours.

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

Oakland today, in numbers

Latitude
37.8°N — 74 of 121 from the north
Today's peak
6.7 (High) — 62 of 121 nationally
Peak arrives
1pm local (GMT-7)
At or above 6
3 hours, 12pm to 3pm
At or above 3
6 hours, 10am to 4pm

The window from 12pm to 3pm is the practical answer for Oakland 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 Hills Behind Oakland Thin The Fog

Marine air reaches the Bay Area through one narrow opening, the Golden Gate, and hits San Francisco’s western neighborhoods first. Oakland lies ten to fifteen miles across the water on the far side of that push, and the Berkeley Hills rise immediately behind the city, capping how far east a shallow deck can spread. Whatever does get across usually thins as the ground on this side heats.

The result is that Oakland clears while San Francisco stays under stratus, on the same morning, at the same hour. A summer afternoon sitting in the low 60s under fog on the city’s ocean side can be in the low 80s here. Coastal fog statistics for this stretch of California do not transfer across the Bay, and Oakland’s sky is open a good deal more often than a San Francisco figure would suggest.

Fog season peaks in July and August, driven by coastal upwelling bringing cold water to the surface while inland heat pulls the resulting fog in through the Gate. Even in those months the deck usually breaks here before it breaks to the west, so the split between the two sides of the Bay is widest in the part of the year the sun is highest.

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.

San Jose, CA 38 mi · 37.3°N peak 7.2 Stockton, CA 55 mi · 38.0°N peak 6.7 Sacramento, CA 69 mi · 38.6°N peak 6.8

What does Oakland’s UV index mean today?

4.7 is Moderate. EPA suggests shade around midday, a hat and sunglasses. Today Oakland also reaches 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 Oakland 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 Oakland

What is the UV index in Oakland today?

4.7 right now (Moderate), peaking at 6.7 around 1pm local time. UV stays at 6 or above for 3 hours, from about 12pm to 3pm. This is a modelled value, not a ground measurement.

When is UV strongest in Oakland 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.

Oakland air qualityThe AQI, from a regulatory monitor rather than a model UV across the USWhere Oakland sits against every metro we track

Updated