Hourly Weather | Today Wednesday, May 20, 2026
Active Weather Warnings
Tucson, Arizona
3 PM
Cloudy Weather
91°
Feels Like 93°
0
Humidity: 7%
UV Index: 4
Wind: 9 mph
4 PM
Cloudy Weather
90°
Feels Like 90°
0
Humidity: 8%
UV Index: 3
Wind: 10 mph
5 PM
Cloudy Weather
88°
Feels Like 88°
0
Humidity: 8%
UV Index: 2
Wind: 10 mph
6 PM
Cloudy Weather
86°
Feels Like 84°
0
Humidity: 9%
UV Index: 1
Wind: 9 mph
7 PM
Cloudy Weather
84°
Feels Like 81°
0
Humidity: 10%
UV Index: 0
Wind: 8 mph
8 PM
Cloudy Night
81°
Feels Like 79°
0
Humidity: 12%
UV Index: 0
Wind: 7 mph
9 PM
Cloudy Night
79°
Feels Like 75°
0
Humidity: 14%
UV Index: 0
Wind: 7 mph
10 PM
Cloudy Night
75°
Feels Like 73°
0
Humidity: 16%
UV Index: 0
Wind: 6 mph
11 PM
Cloudy Night
73°
Feels Like 72°
0
Humidity: 18%
UV Index: 0
Wind: 5 mph

Hourly Air Quality Forecast - AQI (US EPA)

3 PM
51 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.69 µg/m³
  • PM10: 11.57 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.1 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

4 PM
52 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.81 µg/m³
  • PM10: 12.19 µg/m³
  • O3: 0.055 ppm
  • NO2: 0.1 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

5 PM
50 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.96 µg/m³
  • PM10: 12.93 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.1 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

6 PM
49 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.06 µg/m³
  • PM10: 13.51 µg/m³
  • O3: 0.053 ppm
  • NO2: 0.1 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

7 PM
48 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.16 µg/m³
  • PM10: 14 µg/m³
  • O3: 0.052 ppm
  • NO2: 0.1 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

8 PM
47 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.34 µg/m³
  • PM10: 14.93 µg/m³
  • O3: 0.051 ppm
  • NO2: 0.2 ppb
  • SO2: 0 ppb
  • CO: 0.07 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

9 PM
47 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.57 µg/m³
  • PM10: 16.14 µg/m³
  • O3: 0.050 ppm
  • NO2: 0.2 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

10 PM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.74 µg/m³
  • PM10: 16.42 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.3 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 PM
39 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.92 µg/m³
  • PM10: 16.48 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.5 ppb
  • SO2: 0 ppb
  • CO: 0.08 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Weather Alerts and Warnings for Tucson

Air Quality Alert

Air Quality Alert issued May 20 at 1:56PM MST by NWS Tucson AZ
May 20, 2:56 PM May 21, 3:00 PM
The Pima County Department of Environmental Quality (PDEQ) has
issued an Ozone Action Day for the Tucson Metro area until 8 PM MST
this evening.

This means that forecast weather conditions combined with existing
ozone levels are expected to result in local maximum 8-hour ozone
concentrations that pose a health risk. Adverse health effects
increase as air quality deteriorates.

Ozone is an air pollutant which can cause breathing difficulties for
children, older adults, as well as persons with respiratory
problems. A decrease in physical activity is recommended.

You are urged to car pool, telecommute, or use mass transit. The use
of gasoline-powered equipment should be reduced or done late in the
day.

For details on this Action Day, visit the PDEQ website at
www.pima.gov/deq or call 520-724-6885.
Updated: May 20, 3:30 PM Source: NWS Alert