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UV index today across the US

Modelled for

UV is highest right now in Atlanta, GA at 7.2 — High. Today's strongest peak among the metros we track is 10.9 in Tucson, arriving around 12pm local time. These are modelled figures, not instrument readings — the distinction matters and we keep it visible.

Every metro we track

#MetroNow Today's peakAt
1 GA Atlanta 7.2 8.6 1pm
2 TX Houston 6.5 9.8 1pm
3 NY New York 5.6 5.6 12pm
4 NM Albuquerque 5.4 10.2 12pm
5 CO Denver 5.1 9.4 1pm
6 CO Fort Collins 5 8.6 12pm
7 PA Pittsburgh 4.9 5 1pm
8 CO Colorado Springs 4.9 8.6 12pm
9 MO St. Louis 4.7 6.7 1pm
10 AZ Tucson 4.6 10.9 12pm
11 AZ Phoenix 4.1 8.7 12pm
12 WI Madison 4 6.2 1pm
13 IL Chicago 3.7 7 1pm
14 MN Minneapolis 3.7 5 2pm
15 UT Salt Lake City 3.5 8.4 1pm
16 WI Milwaukee 3.5 5.9 2pm
17 CA Los Angeles 2.7 9.6 1pm
18 ID Boise 2.7 7.8 2pm
19 NV Reno 2.7 9.5 1pm
20 CA Bakersfield 2.6 9.4 1pm
21 CA Irvine 2.6 9.6 1pm
22 CA Long Beach 2.6 9.6 1pm
23 CA Fresno 2.5 9.1 1pm
24 CA Sacramento 2.1 8.4 1pm
25 WA Spokane 1.7 5.2 1pm
26 OR Eugene 1.6 6.8 1pm
27 CA Oakland 1.3 7.8 1pm
28 WA Seattle 0.3 2.5 2pm

The EPA scale

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.

The scale is open-ended: 11 is not the maximum, it is where the named bands stop. Values above 12 occur at altitude and in the tropics.

Modelled, not measured — and why we say so

Our air-quality numbers come off EPA regulatory monitors: instruments, in places, with identifiers. The UV figures on this site do not. They are computed by the Copernicus atmosphere model and delivered through Open-Meteo's free tier, which is licensed for non-commercial use — which is what this project is.

The honest limits: cloud cover is the model's weakest point, and broken cloud is exactly the condition where a modelled figure and the sky above you diverge. Altitude and reflective ground — snow, water, sand — push real exposure the other way, above what the index implies. Neither correction is applied here, because we do not have the ground truth to apply it with.

We publish it anyway because it is the only free source covering every US location, and a labelled model beats no answer. What we will not do is let it sit next to monitor data and quietly borrow its authority. Our method →

Questions

What is the UV index today?

Across the 28 US metros we track, UV is highest right now in Atlanta, GA at 7.2 (High). Today's strongest peak is 10.9 in Tucson, around 12pm local time.

What UV index is dangerous?

The EPA treats 3 as the point where protection starts being worth it, 6–7 as high, 8–10 as very high, and 11 or more as extreme. That is the agency’s classification of exposure. It is not a statement about your skin, and no index can be — burn time depends on skin type, altitude, reflection and how long you stay out.

Is the UV index measured or forecast?

The numbers here are modelled, not measured. They come from the Copernicus atmosphere model via Open-Meteo. That is a genuine difference from our air-quality pages, where the AQI is read off an EPA regulatory monitor. Cloud cover is the largest source of error in a UV model.

When is UV highest during the day?

Almost always within an hour or two of solar noon, which in most US metros falls between 12pm and 2pm local time — later than people expect, because of daylight saving. Each city page on this site shows the modelled hourly curve and names the peak hour for that location.

Air quality across the USMeasured AQI from EPA monitors and local sensor networks Worst air in the US right nowThe live ranking, refreshed hourly

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