# Idaho air quality today — live AQI by metro

> Source: https://breathecheck.com/air-quality/us/idaho/
> Live AQI for 2 Idaho metros, updated hourly from EPA AirNow. Where the state's air is worst right now, and how far apart its cities are.

# Idaho air quality today

Updated 14 Sep 2026, 22:12 UTC · LIVE 2 metros tracked

Across the 2 Idaho metros BreatheCheck measures, air is worst right now in Boise at AQI 32 (Good) and cleanest in Idaho Falls at AQI 22 .

## Which Idaho city has the worst air quality right now?

| # | Metro | AQI | UV now | Dominant |

| 1 | Boise | 32 Good | 3.6 | O3 |

| 2 | Idaho Falls no page yet | 22 Good | 3.2 | PM2.5 |

## What is the UV index in Idaho today?

The strongest UV in Idaho today is 6.3 (High) in Idaho Falls, arriving around 1pm local time. The mildest of the 2 metros we model here peaks at 5.9 in Boise.

UV is modelled, not measured — unlike the AQI above it, which comes off an instrument. Hour by hour in Boise →

## Smoke the state schedules, and smoke it doesn't

Idaho regulates agricultural smoke field by field and day by day. Crop residue burning requires a permit from the Department of Environmental Quality, covers every harvested field, pasture, CRP acre and food plot regardless of size, and is approved or denied through a daily burn decision published by 11:00 a.m. All of it stops when DEQ issues an air quality forecast, caution, alert, warning or emergency. The operating guidance goes further than a yes or no, telling burners to hold off during radiation inversions and treating subsidence inversions as a judgment about where the smoke will travel once it is up.

The smoke Idaho does not schedule is the larger share. Summer fire smoke reaches the state from Oregon, Washington, California and British Columbia at least as readily as from Idaho’s own fires, and DEQ spends a good part of every summer issuing advisories for smoke it did not permit and cannot call off. Winter runs on the opposite mechanism. The Snake River Plain and the Treasure Valley around Boise are broad, low, open basins that fill with cold air on clear calm nights, and vehicle exhaust, wood heat and industrial emissions stay under that layer until a weather system removes it.

Our own coverage of Idaho stops at Boise. Coeur d’Alene, Idaho Falls, Pocatello and Twin Falls have no page; the northern panhandle in particular is a separate airshed — narrow, mountainous, and much nearer the Canadian fire seasons than the Treasure Valley is.

## Where do these Idaho readings come from?

2 of the 2 metros here report from a named regulatory monitor — Boise, Idaho Falls. The dominant pollutant across Idaho today is O3 in some metros, PM2.5 in others.

We track 2 metropolitan areas in Idaho, not the whole state, and 1 of them has a page of its own. There is no state-wide average here on purpose: averaging 2 metros into one figure would invent a value for all the ground between them. How we measure, and what we refuse to estimate →

## Neighbouring states

Smoke and inversions do not stop at a state line, so when Idaho looks wrong the answer is often next door.

## Related

Updated 14 Sep 2026, 22:12 UTC