Air quality index for Phoenix, as of (America/Phoenix). Values update hourly — see this page for the current reading and hourly forecast. Today's peak: AQI 61 at 11:00 local time.

airindex·today

Air Quality in Phoenix

Air quality in Phoenix is at its worst point for the day right now — AQI 61 (moderate). Today's main contributor is coarse particulate matter (PM₁₀), at 47 µg/m³. The WHO 24-hour guideline is 45 µg/m³, so today's level runs at about 1× that value.

Now, Oct 17at 11:00
61Moderate
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

By pollutant

  • PM₁₀ coarse particles · sets the index nowAQI 61
  • PM₂.₅ fine particlesAQI 44
  • O₃ ozoneAQI 32
  • NO₂ nitrogen dioxideAQI 1
  • CO carbon monoxideAQI 1
  • SO₂ sulfur dioxideAQI 0
Unusually sensitive people should consider reducing prolonged or intense outdoor activity

Modeled forecast data. AQI values come from atmospheric models (CAMS via Open-Meteo), not local monitoring stations. Readings can differ from ground-level conditions — for exact street-level values, consult an official air quality station near you. The forecast is calculated for a grid square, roughly 11 km across Europe and 45 km elsewhere, and air quality can vary within one square.

The next 48 hours

Hourly air quality index for Phoenix · Local time (MST)

Today, Oct 17
Tomorrow, Oct 18
50
Peak 61 · 11:00
Peak 41 · 18:00
0:00
6:00
12:00
18:00
0:00
6:00
12:00
18:00

Good ≤ 50

Now
Show hourly data table
TimeAQIPM₂.₅µg/m³PM₁₀µg/m³O₃µg/m³NO₂µg/m³SO₂µg/m³COmg/m³°C
Today
00:00529.672762.50.40.1424°
01:00529.170732.20.50.1424°
02:00529.271712.10.50.1423°
03:00539.572702.10.50.1422°
04:00539.572702.20.60.1423°
05:00549.570692.50.60.1422°
06:00559.770673.30.60.1522°
07:00561070644.40.60.1521°
08:00571171644.90.60.1622°
09:00581168684.30.60.1622°
10:00591072753.20.60.1524°
11:00617.547802.40.60.1426°
12:00616.234842.00.60.1427°
13:00596.334862.00.60.1428°
14:00586.435872.20.60.1429°
15:00576.028872.60.60.1429°
16:00564.817843.40.70.1528°
17:00554.69.7805.10.70.1529°
18:00546.08.3719.00.70.1727°
19:00527.48.659140.70.1827°
20:00517.17.751170.70.1921°
21:00485.86.351150.60.1821°
22:00444.85.356110.60.1621°
23:00413.94.2597.80.50.1521°
Tomorrow
00:00393.94.6586.80.50.1420°
01:00364.46.2566.60.50.1520°
02:00345.18.1546.50.50.1521°
03:00315.711546.10.50.1520°
04:00295.69.2555.80.60.1522°
05:00284.44.9565.90.60.1521°
06:00273.94.3566.80.60.1521°
07:00264.64.9578.00.60.1618°
08:00265.56.0608.40.60.1720°
09:00265.45.9677.00.60.1623°
10:00275.16.9764.80.60.1524°
11:00286.318843.00.60.1527°
12:00306.917892.10.60.1428°
13:00326.58.8921.60.60.1429°
14:00347.915931.60.60.1328°
15:00368.114950.10.60.1229°
16:00388.013950.00.60.1228°
17:00408.312874.20.70.1426°
18:0041141665220.80.2323°
19:0041212335460.90.3423°
20:0038252713631.00.4122°
21:003325277.0651.00.4221°
22:003524268.0591.00.3921°
23:0038232410530.90.3520°

Today at a glance

Worst hour
11:00
peaks at AQI 61
Tomorrow
Better, peak 41
peak at 18:00

The week, hour by hour

The index backs off tomorrow, peaking at AQI 41 (good) around 18:00. Over the 5-day forecast the daily peaks run Saturday (moderate), Sunday (good), Monday (moderate), Tuesday (moderate), and Wednesday (good), so today is the worst of the stretch.

Each cell is one forecast hour, coloured by air quality band. A ring marks the day's worst hour. The blue ring marks the current hour.

TodayOct 17
Peak 61 at 11:00
Drizzle29° / 21°
SunOct 18
Peak 41 at 18:00
Rain29° / 18°
MonOct 19
Peak 55 at 12:00
Light drizzle29° / 19°
TueOct 20
Peak 53 at 00:00
Overcast31° / 25°
WedOct 21
Peak 43 at 00:00
Light drizzle31° / 25°

Pollutants right now

Every pollutant on the same AQI scale as the big number above. The index only ever equals the worst score — pollutants don't add up.

050100150+
PM₁₀coarse particles · sets the index now
61
PM₂.₅fine particles
44
O₃ozone
32
NO₂nitrogen dioxide
1
COcarbon monoxide
1
SO₂sulfur dioxide
0
GoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardous

The colors cover a wide area, not a street. The forecast works in squares of roughly 11 km across Europe and 45 km elsewhere, so the air where you actually are can differ from the shade under the city.

Check air quality in: Tempe Junction · Deer Valley · Mesa · Surprise · Maryvale

About Phoenix

CountryUnited States, Arizona
TimezoneAmerica/Phoenix (UTC-7)
Coordinates33.45° N, 112.07° W
Population≈ 1.65M

Air quality in Phoenix — common questions

What is the air quality in Phoenix right now?

The current air quality index (AQI) in Phoenix is 61 (Moderate). Today's forecast peak is AQI 61 (Moderate) at 11:00 local time, and tomorrow's forecast peak is AQI 41. These values come from the CAMS forecast model, not from a local monitoring station.

When is air quality expected to be worst in Phoenix today?

Today's forecast puts the highest AQI in Phoenix at 11:00 in the morning, reaching 61. The largest contributor right now is PM₁₀. Air quality shifts through the day with traffic, wind, how well the air mixes and sunlight, so the hourly chart above shows the pattern for today and tomorrow.

What will the air quality be in Phoenix tomorrow?

Tomorrow's forecast peak for Phoenix is AQI 41 (Good) around 18:00 local time, lower than today's peak of 61. A next-day forecast is less certain than today's, so check back in the morning for the updated hourly curve.

Which pollutants drive the AQI in Phoenix today?

The air quality index in Phoenix is set by PM₁₀ right now. The modelled level this hour is 47 µg/m³ — 1.0× the World Health Organization's 2021 guideline of 45 µg/m³. The others follow: PM₂.₅ (AQI 44), O₃ (AQI 32), NO₂ (AQI 1), and CO (AQI 1).
Pollutant levels in Phoenix at the current hour
PollutantSub-indexLevelWHO 2021Vs guideline
PM₁₀6147 µg/m³45 µg/m³ (24h)1.0×
PM₂.₅447.5 µg/m³15 µg/m³ (24h)0.5×
O₃3280 µg/m³100 µg/m³ (8h)0.8×
NO₂12.4 µg/m³25 µg/m³ (24h)0.1×
CO10.14 mg/m³4 mg/m³ (24h)0.04×
SO₂00.6 µg/m³40 µg/m³ (24h)0.02×
The overall AQI is the highest of the six sub-indices, so the pollutant with the highest sub-index is the one setting the number shown on this page. Sub-indices are computed over the EPA's averaging periods, while the levels are modelled values for the current hour.

Is air quality improving in Phoenix this week?

Over the 5-day forecast, daily peak AQI in Phoenix falls from 61 to 43. These are peak values: each day still has cleaner and dirtier hours, which the chart above shows.

How is air quality forecast for Phoenix, Arizona, United States?

Air quality for Phoenix is forecast with the Copernicus Atmosphere Monitoring Service (CAMS), operated by ECMWF. CAMS models hourly levels of PM2.5, PM10, ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide. Phoenix lies at 33.4° N in the Northern Hemisphere, which sets the seasonal pattern of sunlight that drives much of the chemistry behind these pollutants. AQI values on this page use the US EPA scale.
About the Air Quality Index

What is the Air Quality Index (AQI)?

The Air Quality Index (AQI) is a tool developed by the U.S. Environmental Protection Agency (EPA) to communicate how clean or polluted the air is and what health effects may be of concern. The AQI runs from 0 to 500 and is divided into six color-coded categories: Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous.

How do I read the AQI values?

Lower AQI values mean cleaner air. An AQI of 0–50 (green) is Good, 51–100 (yellow) is Moderate, 101–150 (orange) is Unhealthy for Sensitive Groups, 151–200 (red) is Unhealthy, 201–300 (purple) is Very Unhealthy, and 301–500 (maroon) is Hazardous. When the AQI exceeds 100, air quality is considered unhealthy — at first for sensitive groups, then for everyone as the AQI rises.

Who are the sensitive groups?

Sensitive groups include people with heart or lung disease, older adults, children and teenagers, people who are pregnant, and people who are active outdoors. These groups are more likely to be affected when air quality is poor. If you are in a sensitive group, you can reduce your exposure by taking fewer and shorter outdoor walks when the AQI is elevated.

Which pollutants are measured?

The AQI covers five major pollutants regulated under the Clean Air Act: ground-level ozone (O₃), particle pollution (PM₂.₅ and PM₁₀), carbon monoxide (CO), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂). An AQI value is calculated for each pollutant, and the highest value determines the overall AQI.

Where does the air quality data come from?

The hourly air quality data comes from the Copernicus Atmosphere Monitoring Service (CAMS), which provides global atmospheric composition forecasts. The data is accessed via Open-Meteo, which provides free, open-source weather and air quality APIs. The AQI categories and health guidance follow the EPA AirNow technical standard (EPA-454/B-24-002).

What are the health effects of poor air quality?

Poor air quality can cause respiratory issues, aggravate asthma and allergies, and increase the risk of cardiovascular problems. Fine particles (PM₂.₅) can penetrate deep into the lungs and bloodstream. The World Health Organization estimates that air pollution causes millions of premature deaths worldwide each year.

How often is the air quality forecast updated?

The CAMS air quality forecast is updated regularly using atmospheric models. Weather data such as temperature and cloud cover comes from Open-Meteo. The forecast provides up to 5 days of hourly air quality predictions.

AQI Levels (US EPA Standard)

Good (0–50) — Air quality is satisfactory — it's a great day to be active outside
Moderate (51–100) — Unusually sensitive people should consider reducing prolonged or intense outdoor activity
Unhealthy for Sensitive Groups (101–150) — Sensitive groups should reduce prolonged or intense outdoor activity. Take more breaks and watch for symptoms such as coughing or shortness of breath
Unhealthy (151–200) — Everyone should reduce prolonged or intense outdoor activity. Sensitive groups should avoid outdoor exertion. Consider moving activities indoors
Very Unhealthy (201–300) — Everyone should avoid prolonged or intense outdoor exertion. Sensitive groups should avoid all outdoor physical activity. Move activities indoors or reschedule
Hazardous (301–500) — Health warning — everyone should avoid all outdoor physical activity. Stay indoors and keep activity levels light. Follow tips for keeping particle levels low indoors

AQI categories and health guidance: EPA AirNow (EPA-454/B-24-002, May 2024). Air quality data: CAMS/Copernicus via Open-Meteo.