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

Dangerous Heat and Heavy Rainfall into the Weekend

Hot temperatures and high humidity are forecast to continue across the mid-Mississippi Valley into this weekend. Heat Advisories remain in effect. Heavy to excessive rainfall occurring at times through the weekend could bring areas of flooding to parts of the northern Rockies, upper Midwest, central Great Lakes, and southern New England. Read More >

Current conditions at

Gaithersburg - Montgomery County Airport (KGAI)

Lat: 39.17°NLon: 77.17°WElev: 495ft.

Fair

69°F

21°C

Humidity 66%
Wind Speed Vrbl 6 mph
Barometer 30.18 in (1022.8 mb)
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Last update 19 Sep 9:56 am EDT
Extended Forecast for

2 Miles NNW Olney MD

  • Today

    Today: Partly sunny, with a high near 77. East wind around 6 mph.

    High: 77 °F

    Partly Sunny

  • Tonight

    Tonight: A slight chance of showers before 4am, then a slight chance of showers after 5am. Mostly cloudy, with a low around 64. East wind around 7 mph. Chance of precipitation is 20%.

    Low: 64 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Sunday

    Sunday: A chance of showers between 2pm and 5pm. Mostly cloudy, with a high near 82. South wind 8 to 11 mph, with gusts as high as 20 mph. Chance of precipitation is 40%.

    High: 82 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: Showers and thunderstorms likely. Mostly cloudy, with a low around 60. Light and variable wind becoming north 5 to 9 mph after midnight. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 60 °F

    Showers
    Likely

  • Monday

    Monday: A chance of showers, mainly after 2pm. Partly sunny, with a high near 70. Northeast wind 8 to 10 mph. Chance of precipitation is 30%.

    High: 70 °F

    Chance
    Showers

  • Monday Night

    Monday Night: A chance of showers. Mostly cloudy, with a low around 55. Chance of precipitation is 40%.

    Low: 55 °F

    Chance
    Showers

  • Tuesday

    Tuesday: Showers likely. Mostly cloudy, with a high near 63. Chance of precipitation is 60%.

    High: 63 °F

    Showers
    Likely

  • Tuesday Night

    Tuesday Night: A chance of showers. Mostly cloudy, with a low around 52. Chance of precipitation is 50%.

    Low: 52 °F

    Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers. Mostly cloudy, with a high near 59. Chance of precipitation is 40%.

    High: 59 °F

    Chance
    Showers

Detailed Forecast

Today
Partly sunny, with a high near 77. East wind around 6 mph.
Tonight
A slight chance of showers before 4am, then a slight chance of showers after 5am. Mostly cloudy, with a low around 64. East wind around 7 mph. Chance of precipitation is 20%.
Sunday
A chance of showers between 2pm and 5pm. Mostly cloudy, with a high near 82. South wind 8 to 11 mph, with gusts as high as 20 mph. Chance of precipitation is 40%.
Sunday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 60. Light and variable wind becoming north 5 to 9 mph after midnight. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Monday
A chance of showers, mainly after 2pm. Partly sunny, with a high near 70. Northeast wind 8 to 10 mph. Chance of precipitation is 30%.
Monday Night
A chance of showers. Mostly cloudy, with a low around 55. Chance of precipitation is 40%.
Tuesday
Showers likely. Mostly cloudy, with a high near 63. Chance of precipitation is 60%.
Tuesday Night
A chance of showers. Mostly cloudy, with a low around 52. Chance of precipitation is 50%.
Wednesday
A chance of showers. Mostly cloudy, with a high near 59. Chance of precipitation is 40%.
Wednesday Night
A chance of showers. Mostly cloudy, with a low around 52. Chance of precipitation is 50%.
Thursday
A chance of showers. Mostly cloudy, with a high near 61. Chance of precipitation is 40%.
Thursday Night
A slight chance of showers. Mostly cloudy, with a low around 51. Chance of precipitation is 20%.
Friday
A slight chance of showers. Partly sunny, with a high near 66. Chance of precipitation is 20%.
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ABOUT THIS FORECAST

 
Point Forecast:
2 Miles NNW Olney MD
 39.16°N 77.09°W (Elev. 449 ft)
Last Update:
7:52 am EDT Sep 19, 2026
Forecast Valid:
10am EDT Sep 19, 2026-6pm EDT Sep 25, 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