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

77°F

25°C

Humidity 100%
Wind Speed Vrbl 6 mph
Barometer 30.08 in (1019.4 mb)
Dewpoint 77°F (25°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 16 Jul 1:56 am EDT
Extended Forecast for

Olney MD

  • Overnight

    Overnight: Mostly cloudy, with a low around 73. Calm wind.

    Low: 73 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Showers and thunderstorms likely, mainly after 5pm. Partly sunny, with a high near 90. South wind 3 to 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 90 °F

    Partly Sunny
    then T-storms
    Likely

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms, mainly before midnight. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 74. Southwest wind around 7 mph. Chance of precipitation is 30%.

    Low: 74 °F

    Heavy Rain

  • Thursday

    Thursday: A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 94. Heat index values as high as 101. West wind 8 to 10 mph. Chance of precipitation is 30%.

    High: 94 °F

    Mostly Sunny
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms before 8pm. Partly cloudy, with a low around 75. West wind around 6 mph. Chance of precipitation is 30%.

    Low: 75 °F

    Chance
    T-storms then
    Partly Cloudy

  • Friday

    Friday: A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 88. Chance of precipitation is 40%.

    High: 88 °F

    Mostly Sunny
    then Chance
    T-storms

  • Friday Night

    Friday Night: A chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 70. Chance of precipitation is 30%.

    Low: 70 °F

    Chance
    T-storms then
    Mostly Cloudy

  • Saturday

    Saturday: A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 85. Chance of precipitation is 50%.

    High: 85 °F

    Partly Sunny
    then Chance
    T-storms

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Chance of precipitation is 40%.

    Low: 71 °F

    Chance
    T-storms

Detailed Forecast

Overnight
Mostly cloudy, with a low around 73. Calm wind.
Wednesday
Showers and thunderstorms likely, mainly after 5pm. Partly sunny, with a high near 90. South wind 3 to 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
A chance of showers and thunderstorms, mainly before midnight. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 74. Southwest wind around 7 mph. Chance of precipitation is 30%.
Thursday
A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 94. Heat index values as high as 101. West wind 8 to 10 mph. Chance of precipitation is 30%.
Thursday Night
A chance of showers and thunderstorms before 8pm. Partly cloudy, with a low around 75. West wind around 6 mph. Chance of precipitation is 30%.
Friday
A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 88. Chance of precipitation is 40%.
Friday Night
A chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 70. Chance of precipitation is 30%.
Saturday
A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 85. Chance of precipitation is 50%.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Chance of precipitation is 40%.
Sunday
A chance of showers, then showers likely and possibly a thunderstorm after 2pm. Mostly cloudy, with a high near 87. Chance of precipitation is 70%.
Sunday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 70. Chance of precipitation is 60%.
Monday
A chance of showers and thunderstorms. Partly sunny, with a high near 84. Chance of precipitation is 40%.
Monday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 68. Chance of precipitation is 30%.
Tuesday
A chance of showers and thunderstorms. Partly sunny, with a high near 85. Chance of precipitation is 40%.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Olney MD
 39.16°N 77.09°W (Elev. 449 ft)
Last Update:
1:30 am EDT Jul 16, 2025
Forecast Valid:
2am EDT Jul 16, 2025-6pm EDT Jul 22, 2025
 
Forecast Discussion
 
Get as KML Get as XML

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