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

Prolonged, Intense Heat Wave; Excessive Rainfall in the Southern Rockies and Central Plains into the Upper Midwest

Extremely dangerous heat persists through Thursday with widespread daily temperature records. Monsoonal moisture continues to bring heavy rain and flash flooding to New Mexico and west Texas through Thursday, especially in the burn scar areas. Thunderstorms and heavy to excessive rain will continue to bring a flash flood threat from the Central Plains into the Upper Midwest. Read More >

Hazardous Weather Conditions

Current conditions at

Gaithersburg - Montgomery County Airport (KGAI)

Lat: 39.17°NLon: 77.17°WElev: 495ft.

N/A

Humidity NA
Wind Speed NA
Barometer NA
Dewpoint N/A
Visibility NA
Last update *** Not a current observation ***
Extended Forecast for

Ashton-Sandy Spring MD

Heat Advisory June 25, 11:00am until June 25, 09:00pm
Click here for hazard details and duration
Heat Advisory

  • Today

    Today: Isolated showers and thunderstorms after 2pm. Sunny, with a high near 96. Heat index values as high as 105. Calm wind becoming west around 6 mph in the afternoon. Chance of precipitation is 20%.

    High: 96 °F

    Sunny then
    Isolated
    T-storms

  • Tonight

    Tonight: Scattered showers and thunderstorms before 2am, then isolated showers between 2am and 3am. Partly cloudy, with a low around 75. Light north wind. Chance of precipitation is 30%.

    Low: 75 °F

    Scattered
    T-storms then
    Scattered
    Showers

  • Thursday

    Thursday: A chance of showers, then showers likely and possibly a thunderstorm after 2pm. Mostly sunny, with a high near 92. Heat index values as high as 102. Calm wind becoming west around 5 mph in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

    High: 92 °F

    Chance
    Showers then
    Showers
    Likely

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm before 2am, then a chance of showers and thunderstorms between 2am and 5am, then a chance of showers after 5am. Mostly cloudy, with a low around 70. East wind 3 to 5 mph. Chance of precipitation is 70%. New rainfall amounts between a half and three quarters of an inch possible.

    Low: 70 °F

    Showers
    Likely

  • Friday

    Friday: A chance of showers, with thunderstorms also possible after 11am. Mostly cloudy, with a high near 80. East wind around 7 mph. Chance of precipitation is 50%.

    High: 80 °F

    Chance
    Showers then
    Chance
    T-storms

  • Friday Night

    Friday Night: A chance of showers and thunderstorms, mainly before 2am. Mostly cloudy, with a low around 71. Chance of precipitation is 30%.

    Low: 71 °F

    Chance
    T-storms

  • Saturday

    Saturday: A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 88. Chance of precipitation is 50%.

    High: 88 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms before 2am. Mostly cloudy, with a low around 72. Chance of precipitation is 30%.

    Low: 72 °F

    Chance
    T-storms

  • Sunday

    Sunday: A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 89. Chance of precipitation is 50%.

    High: 89 °F

    Mostly Sunny
    then Chance
    T-storms

Detailed Forecast

Today
Isolated showers and thunderstorms after 2pm. Sunny, with a high near 96. Heat index values as high as 105. Calm wind becoming west around 6 mph in the afternoon. Chance of precipitation is 20%.
Tonight
Scattered showers and thunderstorms before 2am, then isolated showers between 2am and 3am. Partly cloudy, with a low around 75. Light north wind. Chance of precipitation is 30%.
Thursday
A chance of showers, then showers likely and possibly a thunderstorm after 2pm. Mostly sunny, with a high near 92. Heat index values as high as 102. Calm wind becoming west around 5 mph in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
Thursday Night
Showers likely and possibly a thunderstorm before 2am, then a chance of showers and thunderstorms between 2am and 5am, then a chance of showers after 5am. Mostly cloudy, with a low around 70. East wind 3 to 5 mph. Chance of precipitation is 70%. New rainfall amounts between a half and three quarters of an inch possible.
Friday
A chance of showers, with thunderstorms also possible after 11am. Mostly cloudy, with a high near 80. East wind around 7 mph. Chance of precipitation is 50%.
Friday Night
A chance of showers and thunderstorms, mainly before 2am. Mostly cloudy, with a low around 71. Chance of precipitation is 30%.
Saturday
A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 88. Chance of precipitation is 50%.
Saturday Night
A chance of showers and thunderstorms before 2am. Mostly cloudy, with a low around 72. Chance of precipitation is 30%.
Sunday
A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 89. Chance of precipitation is 50%.
Sunday Night
A chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 72. Chance of precipitation is 30%.
Monday
Showers likely and possibly a thunderstorm. Mostly sunny, with a high near 90. Chance of precipitation is 60%.
Monday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 74. Chance of precipitation is 60%.
Tuesday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 90. Chance of precipitation is 60%.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Ashton-Sandy Spring MD
 39.15°N 77.01°W (Elev. 449 ft)
Last Update:
4:31 am EDT Jun 25, 2025
Forecast Valid:
7am EDT Jun 25, 2025-6pm EDT Jul 1, 2025
 
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