National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Gaithersburg - Montgomery County Airport (KGAI)

Lat: 39.17°NLon: 77.17°WElev: 495ft.

Fair

74°F

23°C

Humidity 57%
Wind Speed Calm
Barometer 30.16 in (1022.2 mb)
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Last update 21 Aug 10:56 am EDT
Extended Forecast for

Olney MD

  • Today

    Today: Mostly sunny, with a high near 81. Northeast wind 3 to 5 mph.

    High: 81 °F

    Mostly Sunny

  • Tonight

    Tonight: A chance of showers, mainly after 3am. Patchy fog between 4am and 5am. Otherwise, increasing clouds, with a low around 66. Calm wind. Chance of precipitation is 30%.

    Low: 66 °F

    Mostly Cloudy
    then Chance
    Showers and
    Patchy Fog

  • Saturday

    Saturday: Showers and thunderstorms before noon, then showers likely and possibly a thunderstorm between noon and 4pm, then a chance of showers and thunderstorms after 4pm. High near 77. East wind 3 to 6 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

    High: 77 °F

    Showers

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms, mainly between 1am and 2am. Mostly cloudy, with a low around 65. Light and variable wind. Chance of precipitation is 40%.

    Low: 65 °F

    Chance
    T-storms then
    Chance
    Showers

  • Sunday

    Sunday: A slight chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 82. West wind 3 to 8 mph. Chance of precipitation is 20%.

    High: 82 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 62.

    Low: 62 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 80.

    High: 80 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 61.

    Low: 61 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 79.

    High: 79 °F

    Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 81. Northeast wind 3 to 5 mph.
Tonight
A chance of showers, mainly after 3am. Patchy fog between 4am and 5am. Otherwise, increasing clouds, with a low around 66. Calm wind. Chance of precipitation is 30%.
Saturday
Showers and thunderstorms before noon, then showers likely and possibly a thunderstorm between noon and 4pm, then a chance of showers and thunderstorms after 4pm. High near 77. East wind 3 to 6 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.
Saturday Night
A chance of showers and thunderstorms, mainly between 1am and 2am. Mostly cloudy, with a low around 65. Light and variable wind. Chance of precipitation is 40%.
Sunday
A slight chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 82. West wind 3 to 8 mph. Chance of precipitation is 20%.
Sunday Night
Mostly clear, with a low around 62.
Monday
Sunny, with a high near 80.
Monday Night
Mostly clear, with a low around 61.
Tuesday
Sunny, with a high near 79.
Tuesday Night
Partly cloudy, with a low around 64.
Wednesday
A chance of showers and thunderstorms. Mostly sunny, with a high near 81. Chance of precipitation is 30%.
Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 68. Chance of precipitation is 50%.
Thursday
A chance of showers and thunderstorms. Partly sunny, with a high near 81. Chance of precipitation is 50%.
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ABOUT THIS FORECAST

 
Point Forecast:
Olney MD
 39.14°N 77.1°W (Elev. 449 ft)
Last Update:
10:52 am EDT Aug 21, 2026
Forecast Valid:
11am EDT Aug 21, 2026-6pm EDT Aug 27, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation