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Today Hourly 7 days 30 days Air Quality
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Hourly Weather | Today › Tuesday, July 21, 2026
Active Weather Warnings
Caldwell, Idaho
3 AM
Cloudy Weather
79°
Feels Like 75°
0
Humidity: 36%
UV Index: 0
Wind: 9 mph
4 AM
Cloudy Weather
77°
Feels Like 73°
0
Humidity: 37%
UV Index: 0
Wind: 9 mph
5 AM
Cloudy Weather
75°
Feels Like 72°
0
Humidity: 40%
UV Index: 0
Wind: 9 mph
6 AM
Cloudy Night
75°
Feels Like 72°
0
Humidity: 40%
UV Index: 0
Wind: 8 mph
7 AM
Cloudy Weather
73°
Feels Like 72°
0
Humidity: 42%
UV Index: 1
Wind: 8 mph
8 AM
Cloudy Weather
73°
Feels Like 72°
0
Humidity: 44%
UV Index: 2
Wind: 8 mph
9 AM
Cloudy Weather
77°
Feels Like 79°
0
Humidity: 38%
UV Index: 3
Wind: 8 mph
10 AM
Cloudy Weather
81°
Feels Like 82°
0
Humidity: 34%
UV Index: 4
Wind: 8 mph
11 AM
Cloudy Weather
84°
Feels Like 88°
0
Humidity: 30%
UV Index: 5
Wind: 8 mph
12 PM
Cloudy Weather
88°
Feels Like 91°
0
Humidity: 27%
UV Index: 7
Wind: 7 mph
1 PM
Cloudy Weather
90°
Feels Like 97°
0
Humidity: 25%
UV Index: 8
Wind: 7 mph
2 PM
Cloudy Weather
93°
Feels Like 99°
0
Humidity: 23%
UV Index: 8
Wind: 7 mph
3 PM
Cloudy Weather
95°
Feels Like 99°
0
Humidity: 22%
UV Index: 6
Wind: 7 mph
4 PM
Cloudy Weather
97°
Feels Like 99°
0
Humidity: 21%
UV Index: 4
Wind: 7 mph
5 PM
Cloudy Weather
99°
Feels Like 100°
0
Humidity: 20%
UV Index: 3
Wind: 8 mph
6 PM
Cloudy Weather
100°
Feels Like 100°
0
Humidity: 20%
UV Index: 2
Wind: 8 mph
7 PM
Cloudy Weather
99°
Feels Like 97°
0
Humidity: 21%
UV Index: 1
Wind: 7 mph
8 PM
Cloudy Weather
97°
Feels Like 93°
0
Humidity: 24%
UV Index: 0
Wind: 7 mph
9 PM
Cloudy Weather
93°
Feels Like 91°
0
Humidity: 27%
UV Index: 0
Wind: 6 mph
10 PM
Cloudy Night
90°
Feels Like 88°
0
Humidity: 31%
UV Index: 0
Wind: 7 mph
11 PM
Cloudy Night
88°
Feels Like 84°
0
Humidity: 34%
UV Index: 0
Wind: 7 mph

Hourly Air Quality Forecast - AQI (US EPA)

3 AM
167 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 87.12 µg/m³
  • PM10: 88.13 µg/m³
  • O3: 0.076 ppm
  • NO2: 1.6 ppb
  • SO2: 0.6 ppb
  • CO: 0.43 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

4 AM
166 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 86.17 µg/m³
  • PM10: 87.16 µg/m³
  • O3: 0.069 ppm
  • NO2: 1.6 ppb
  • SO2: 0.6 ppb
  • CO: 0.42 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

5 AM
165 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 83.53 µg/m³
  • PM10: 84.52 µg/m³
  • O3: 0.063 ppm
  • NO2: 1.6 ppb
  • SO2: 0.5 ppb
  • CO: 0.41 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

6 AM
164 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 81.19 µg/m³
  • PM10: 82.2 µg/m³
  • O3: 0.057 ppm
  • NO2: 1.6 ppb
  • SO2: 0.4 ppb
  • CO: 0.40 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

7 AM
162 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 78.75 µg/m³
  • PM10: 79.8 µg/m³
  • O3: 0.051 ppm
  • NO2: 1.7 ppb
  • SO2: 0.4 ppb
  • CO: 0.39 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

8 AM
162 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 77.59 µg/m³
  • PM10: 78.69 µg/m³
  • O3: 0.047 ppm
  • NO2: 2 ppb
  • SO2: 0.3 ppb
  • CO: 0.39 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

9 AM
162 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 77.63 µg/m³
  • PM10: 78.78 µg/m³
  • O3: 0.045 ppm
  • NO2: 2.1 ppb
  • SO2: 0.3 ppb
  • CO: 0.39 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

10 AM
161 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 76.28 µg/m³
  • PM10: 77.51 µg/m³
  • O3: 0.051 ppm
  • NO2: 1.9 ppb
  • SO2: 0.3 ppb
  • CO: 0.37 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

11 AM
160 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 74.81 µg/m³
  • PM10: 76.05 µg/m³
  • O3: 0.053 ppm
  • NO2: 1.9 ppb
  • SO2: 0.3 ppb
  • CO: 0.37 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

12 PM
159 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 72.97 µg/m³
  • PM10: 74.19 µg/m³
  • O3: 0.055 ppm
  • NO2: 1.9 ppb
  • SO2: 0.3 ppb
  • CO: 0.36 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

1 PM
156 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 66.26 µg/m³
  • PM10: 67.21 µg/m³
  • O3: 0.067 ppm
  • NO2: 1.5 ppb
  • SO2: 0.3 ppb
  • CO: 0.34 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

2 PM
151 AQI
Unhealthy air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 56.85 µg/m³
  • PM10: 57.64 µg/m³
  • O3: 0.071 ppm
  • NO2: 1.2 ppb
  • SO2: 0.2 ppb
  • CO: 0.31 ppm

Health Recommendations:

Everyone may begin to experience health effects; sensitive groups may experience more serious effects.

3 PM
143 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 52.75 µg/m³
  • PM10: 53.42 µg/m³
  • O3: 0.073 ppm
  • NO2: 1.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.29 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

4 PM
135 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 49.33 µg/m³
  • PM10: 49.92 µg/m³
  • O3: 0.076 ppm
  • NO2: 0.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.27 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

5 PM
126 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 45.84 µg/m³
  • PM10: 46.43 µg/m³
  • O3: 0.076 ppm
  • NO2: 0.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.26 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

6 PM
122 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 44.17 µg/m³
  • PM10: 44.79 µg/m³
  • O3: 0.076 ppm
  • NO2: 0.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.25 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

7 PM
128 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 45.56 µg/m³
  • PM10: 46.23 µg/m³
  • O3: 0.078 ppm
  • NO2: 1.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.25 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

8 PM
132 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 48.26 µg/m³
  • PM10: 48.97 µg/m³
  • O3: 0.079 ppm
  • NO2: 1.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.26 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

9 PM
138 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 50.41 µg/m³
  • PM10: 51.15 µg/m³
  • O3: 0.077 ppm
  • NO2: 1.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.27 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

10 PM
141 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 51.87 µg/m³
  • PM10: 52.67 µg/m³
  • O3: 0.074 ppm
  • NO2: 1.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.27 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

11 PM
142 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 52.25 µg/m³
  • PM10: 53.12 µg/m³
  • O3: 0.068 ppm
  • NO2: 1.4 ppb
  • SO2: 0.1 ppb
  • CO: 0.27 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Caldwell

Air Quality Alert

Air Quality Alert issued July 20 at 8:21AM MDT by NWS Boise ID
Jul 20, 8:21 AM → Jul 21, 8:30 AM
WHAT: Air Quality Advisory because of degraded air quality.

Air Quality Index is forecast to be Unhealthy.

WHERE: Ada, Canyon, Gem, Payette, and Washington Counties.

WHEN: UNTIL 3 PM MDT WEDNESDAY.

IMPACTS: Everyone may begin to experience health effects; members
of sensitive groups may experience more serious health effects.
+ Read More
Air pollutants can cause breathing difficulties for children, the elderly, as well as persons with respiratory problems. Those individuals who are sensitive to increased particulate matter or smoke are encouraged to avoid prolonged or strenuous outdoor activity during this advisory. Open burning is prohibited by air quality rule. It is also recommended that all other individuals limit prolonged or strenuous activity outdoors. THIS STATEMENT IS ISSUED BY THE IDAHO DEPARTMENT OF ENVIRONMENTAL QUALITY, AIR QUALITY GROUP FOR MORE INFORMATION, CONTACT DEQ's Boise Regional Office at (208) 373-0550
Updated: Jul 21, 1:31 AM Source: NWS Alert

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