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Pittsburgh, PA UV Index Today

Modelled for · GMT-4

Right now

5 Moderate

EPA suggests shade around midday, a hat and sunglasses.

Today's peak is 5 (Moderate) at about 1pm local time.

Hour by hour today

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

What the number means

0–2 Low No protection needed for most people.
3–5 Moderate EPA suggests shade around midday, a hat and sunglasses.
6–7 High EPA suggests shade between 10am and 4pm, plus a shirt and sunscreen.
8–10 Very High EPA suggests avoiding the sun between 10am and 4pm where you can.
11+ Extreme EPA describes unprotected skin as at risk of burning in minutes.

Bands and the guidance beside them are the EPA's classification of the WHO scale. They describe exposure, not your skin — we are not going to tell you how long you personally can stay out, and anyone who does is guessing.

Where this number comes from, and how it can be wrong

This is a modelled value, not a measurement. The AQI on our air-quality pages comes off a regulatory monitor — an instrument, in a place, with a serial number. UV here does not. It is computed by the Copernicus atmosphere model and served through Open-Meteo.

The practical consequence: cloud cover is the biggest source of error. The model's idea of the sky over Pittsburgh at noon may not match the sky you are standing under. On a clear day the figure is reliable; under broken cloud it can overstate what reaches the ground. Altitude and surface reflection push the other way — snow and water raise real exposure above what a flat model suggests.

We publish it because it is the best free source that covers every US location, and we label it as modelled every time rather than letting it borrow the authority of the monitor data next door. How we measure, and what we refuse to estimate →

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

Updated