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

68°F

20°C

Humidity 38%
Wind Speed SE 6 mph
Barometer 29.88 in (1013.1 mb)
Dewpoint 41°F (5°C)
Visibility 10.00 mi
Last update 21 Mar 5:56 pm EDT
Extended Forecast for

Olney MD

  • Tonight

    Tonight: Patchy fog after 5am. Otherwise, partly cloudy, with a low around 47. Calm wind becoming southeast around 6 mph in the evening.

    Low: 47 °F

    Partly Cloudy
    then Patchy
    Fog

  • Sunday

    Sunday: Patchy fog before 8am. Otherwise, partly sunny, with a high near 81. Southwest wind 6 to 10 mph, with gusts as high as 20 mph.

    High: 81 °F

    Patchy Fog
    then Mostly
    Sunny

  • Sunday Night

    Sunday Night: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 2am. Low around 48. Southwest wind around 8 mph becoming north in the evening. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 48 °F

    Chance
    T-storms then
    Showers

  • Monday

    Monday: Showers and possibly a thunderstorm before 8am, then a slight chance of rain between 8am and 2pm. High near 56. Northwest wind 14 to 16 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 56 °F

    Showers then
    Slight Chance
    Rain

  • Monday Night

    Monday Night: Mostly clear, with a low around 32. North wind 7 to 10 mph, with gusts as high as 18 mph.

    Low: 32 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 50.

    High: 50 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 36.

    Low: 36 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 58.

    High: 58 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 42.

    Low: 42 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Patchy fog after 5am. Otherwise, partly cloudy, with a low around 47. Calm wind becoming southeast around 6 mph in the evening.
Sunday
Patchy fog before 8am. Otherwise, partly sunny, with a high near 81. Southwest wind 6 to 10 mph, with gusts as high as 20 mph.
Sunday Night
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 2am. Low around 48. Southwest wind around 8 mph becoming north in the evening. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Monday
Showers and possibly a thunderstorm before 8am, then a slight chance of rain between 8am and 2pm. High near 56. Northwest wind 14 to 16 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Monday Night
Mostly clear, with a low around 32. North wind 7 to 10 mph, with gusts as high as 18 mph.
Tuesday
Sunny, with a high near 50.
Tuesday Night
Mostly cloudy, with a low around 36.
Wednesday
Partly sunny, with a high near 58.
Wednesday Night
Mostly cloudy, with a low around 42.
Thursday
Partly sunny, with a high near 64.
Thursday Night
A chance of rain. Mostly cloudy, with a low around 45. Chance of precipitation is 50%.
Friday
A chance of rain. Partly sunny, with a high near 57. Chance of precipitation is 30%.
Friday Night
A chance of rain. Mostly cloudy, with a low around 32. Chance of precipitation is 30%.
Saturday
Mostly sunny, with a high near 50.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Olney MD
 39.16°N 77.06°W (Elev. 486 ft)
Last Update:
6:07 pm EDT Mar 21, 2026
Forecast Valid:
6pm EDT Mar 21, 2026-6pm EDT Mar 28, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation