Hourly Weather | Today Tuesday, September 1, 2026
Gaithersburg, Maryland
12 PM
Cloudy Weather
88°
Feels Like 97°
14
Humidity: 62%
UV Index: 7
Wind: 7 mph
1 PM
Cloudy Weather
90°
Feels Like 100°
18
Humidity: 57%
UV Index: 7
Wind: 8 mph
2 PM
Cloudy Weather
90°
Feels Like 100°
34
Humidity: 53%
UV Index: 7
Wind: 8 mph
3 PM
Cloudy Weather
91°
Feels Like 100°
34
Humidity: 51%
UV Index: 5
Wind: 8 mph
4 PM
Cloudy Weather
93°
Feels Like 99°
39
Humidity: 49%
UV Index: 4
Wind: 8 mph
5 PM
Cloudy Weather
91°
Feels Like 97°
49
Humidity: 51%
UV Index: 2
Wind: 8 mph
6 PM
Cloudy Weather
90°
Feels Like 95°
49
Humidity: 54%
UV Index: 1
Wind: 7 mph
7 PM
Sunny with a Chance of Thunderstorms
86°
Feels Like 91°
61
Humidity: 70%
UV Index: 0
Wind: 6 mph
8 PM
Cloudy Night
84°
Feels Like 91°
22
Humidity: 71%
UV Index: 0
Wind: 6 mph
9 PM
Cloudy Night
81°
Feels Like 88°
17
Humidity: 80%
UV Index: 0
Wind: 6 mph
10 PM
Cloudy Night
79°
Feels Like 84°
17
Humidity: 88%
UV Index: 0
Wind: 5 mph
11 PM
Cloudy Night
75°
Feels Like 82°
17
Humidity: 94%
UV Index: 0
Wind: 5 mph

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 7.42 µg/m³
  • PM10: 7.94 µg/m³
  • O3: 0.053 ppm
  • NO2: 0.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

1 PM
54 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 6.3 µg/m³
  • PM10: 6.68 µg/m³
  • O3: 0.055 ppm
  • NO2: 0.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 5.09 µg/m³
  • PM10: 5.42 µg/m³
  • O3: 0.055 ppm
  • NO2: 0.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.21 µg/m³
  • PM10: 4.5 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.5 ppb
  • SO2: 0.3 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.86 µg/m³
  • PM10: 4.14 µg/m³
  • O3: 0.052 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.

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

Pollutant Concentrations:

  • PM2.5: 3.69 µg/m³
  • PM10: 3.97 µg/m³
  • O3: 0.051 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.

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

Pollutant Concentrations:

  • PM2.5: 3.73 µg/m³
  • PM10: 4.11 µg/m³
  • O3: 0.042 ppm
  • NO2: 1.3 ppb
  • SO2: 0.2 ppb
  • CO: 0.10 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.86 µg/m³
  • PM10: 4.45 µg/m³
  • O3: 0.032 ppm
  • NO2: 2.2 ppb
  • SO2: 0.2 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.94 µg/m³
  • PM10: 4.76 µg/m³
  • O3: 0.026 ppm
  • NO2: 2.8 ppb
  • SO2: 0.1 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.96 µg/m³
  • PM10: 4.97 µg/m³
  • O3: 0.021 ppm
  • NO2: 2.8 ppb
  • SO2: 0.1 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

10 PM
17 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 3.98 µg/m³
  • PM10: 5.15 µg/m³
  • O3: 0.018 ppm
  • NO2: 2.7 ppb
  • SO2: 0.1 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

11 PM
16 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 3.92 µg/m³
  • PM10: 5.24 µg/m³
  • O3: 0.016 ppm
  • NO2: 2.7 ppb
  • SO2: 0.1 ppb
  • CO: 0.12 ppm

Health Recommendations:

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