Hourly Weather | Today Tuesday, July 21, 2026
Gaithersburg, Maryland
4 AM
Stormy Weather
73°
Feels Like 75°
46
Humidity: 94%
UV Index: 0
Wind: 6 mph
5 AM
Cloudy Weather
73°
Feels Like 79°
24
Humidity: 95%
UV Index: 0
Wind: 6 mph
6 AM
Cloudy Weather
73°
Feels Like 77°
19
Humidity: 95%
UV Index: 0
Wind: 6 mph
7 AM
Cloudy Weather
73°
Feels Like 79°
19
Humidity: 98%
UV Index: 0
Wind: 6 mph
8 AM
Cloudy Weather
73°
Feels Like 81°
20
Humidity: 96%
UV Index: 1
Wind: 6 mph
9 AM
Cloudy Weather
77°
Feels Like 84°
20
Humidity: 91%
UV Index: 1
Wind: 7 mph
10 AM
Cloudy Weather
79°
Feels Like 88°
20
Humidity: 86%
UV Index: 1
Wind: 7 mph
11 AM
Cloudy Weather
81°
Feels Like 91°
20
Humidity: 81%
UV Index: 2
Wind: 8 mph
12 PM
Cloudy Weather
84°
Feels Like 93°
20
Humidity: 74%
UV Index: 3
Wind: 8 mph
1 PM
Cloudy Weather
86°
Feels Like 97°
25
Humidity: 68%
UV Index: 3
Wind: 8 mph
2 PM
Cloudy Weather
88°
Feels Like 99°
34
Humidity: 62%
UV Index: 3
Wind: 9 mph
3 PM
Cloudy Weather
88°
Feels Like 97°
34
Humidity: 64%
UV Index: 3
Wind: 9 mph
4 PM
Cloudy Weather
84°
Feels Like 93°
40
Humidity: 69%
UV Index: 2
Wind: 9 mph
5 PM
Stormy Weather
82°
Feels Like 88°
63
Humidity: 84%
UV Index: 1
Wind: 8 mph
6 PM
Stormy Weather
79°
Feels Like 81°
63
Humidity: 86%
UV Index: 0
Wind: 8 mph
7 PM
Cloudy Weather
81°
Feels Like 86°
49
Humidity: 85%
UV Index: 0
Wind: 9 mph
8 PM
Stormy Weather
79°
Feels Like 81°
61
Humidity: 86%
UV Index: 0
Wind: 9 mph
9 PM
Stormy Weather
77°
Feels Like 82°
54
Humidity: 91%
UV Index: 0
Wind: 8 mph
10 PM
Cloudy Weather
75°
Feels Like 82°
49
Humidity: 96%
UV Index: 0
Wind: 7 mph
11 PM
Cloudy Weather
75°
Feels Like 82°
34
Humidity: 97%
UV Index: 0
Wind: 7 mph

Hourly Air Quality Forecast - AQI (US EPA)

4 AM
26 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 6.26 µg/m³
  • PM10: 6.61 µg/m³
  • O3: 0.018 ppm
  • NO2: 1 ppb
  • SO2: 0.2 ppb
  • CO: 0.18 ppm

Health Recommendations:

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

5 AM
25 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 6.03 µg/m³
  • PM10: 6.36 µg/m³
  • O3: 0.016 ppm
  • NO2: 0.9 ppb
  • SO2: 0.2 ppb
  • CO: 0.16 ppm

Health Recommendations:

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

6 AM
24 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 5.88 µg/m³
  • PM10: 6.18 µg/m³
  • O3: 0.015 ppm
  • NO2: 0.9 ppb
  • SO2: 0.2 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

7 AM
24 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 5.72 µg/m³
  • PM10: 6.03 µg/m³
  • O3: 0.015 ppm
  • NO2: 1.1 ppb
  • SO2: 0.2 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

8 AM
23 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 5.52 µg/m³
  • PM10: 5.84 µg/m³
  • O3: 0.015 ppm
  • NO2: 1.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

9 AM
21 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 5.14 µg/m³
  • PM10: 5.45 µg/m³
  • O3: 0.017 ppm
  • NO2: 1.5 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

10 AM
20 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 4.72 µg/m³
  • PM10: 5.03 µg/m³
  • O3: 0.020 ppm
  • NO2: 1.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

11 AM
22 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.45 µg/m³
  • PM10: 4.76 µg/m³
  • O3: 0.024 ppm
  • NO2: 1.1 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

12 PM
28 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.78 µg/m³
  • PM10: 4.03 µg/m³
  • O3: 0.030 ppm
  • NO2: 0.8 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

1 PM
30 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.13 µg/m³
  • PM10: 3.33 µg/m³
  • O3: 0.033 ppm
  • NO2: 0.6 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

2 PM
32 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.71 µg/m³
  • PM10: 2.88 µg/m³
  • O3: 0.034 ppm
  • NO2: 0.5 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

3 PM
33 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.38 µg/m³
  • PM10: 2.5 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.5 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

4 PM
33 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.23 µg/m³
  • PM10: 2.31 µg/m³
  • O3: 0.036 ppm
  • NO2: 0.6 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 2.02 µg/m³
  • PM10: 2.08 µg/m³
  • O3: 0.035 ppm
  • NO2: 0.7 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.76 µg/m³
  • PM10: 1.81 µg/m³
  • O3: 0.035 ppm
  • NO2: 0.8 ppb
  • SO2: 0.1 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.64 µg/m³
  • PM10: 1.69 µg/m³
  • O3: 0.034 ppm
  • NO2: 1 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.68 µg/m³
  • PM10: 1.74 µg/m³
  • O3: 0.033 ppm
  • NO2: 1.1 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.73 µg/m³
  • PM10: 1.79 µg/m³
  • O3: 0.031 ppm
  • NO2: 1.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.76 µg/m³
  • PM10: 1.82 µg/m³
  • O3: 0.028 ppm
  • NO2: 1.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.71 µg/m³
  • PM10: 1.77 µg/m³
  • O3: 0.026 ppm
  • NO2: 1.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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