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

Heavy Rainfall in the Southern Plains and Mississippi Valley; Thunderstorms in Eastern Colorado on Thursday

A multiple day heavy rainfall event will begin to set up from the Southern Plains into the Mississippi Valley Thursday, peaking in intensity over the holiday weekend. Widely scattered thunderstorms are expected to develop across eastern Colorado Thursday afternoon and evening. Large hail will be the primary hazard. Read More >

Current conditions at

Granby-Grand County Airport (KGNB)

Lat: 40.09°NLon: 105.92°WElev: 8207ft.

Fair

32°F

0°C

Humidity 96%
Wind Speed Calm
Barometer 30.20 in
Dewpoint 31°F (-1°C)
Visibility 10.00 mi
Last update 21 May 2:15 am MDT
Extended Forecast for

Grand Lake CO

  • Overnight

    Overnight: Mostly clear, with a low around 26. Calm wind.

    Low: 26 °F

    Mostly Clear

  • Thursday

    Thursday: A slight chance of rain and snow showers between 9am and noon, then a chance of rain showers. Some thunder is also possible. Partly sunny, with a high near 57. Light and variable wind becoming west southwest 5 to 10 mph in the morning. Winds could gust as high as 18 mph. Chance of precipitation is 40%. Little or no snow accumulation expected.

    High: 57 °F

    Slight Chance
    Rain/Snow
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: Rain and snow showers likely before 3am, then a chance of snow showers. Some thunder is also possible. Mostly cloudy, with a low around 27. Southwest wind 3 to 7 mph. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.

    Low: 27 °F

    Rain/Snow
    Likely then
    Chance
    Rain/Snow

  • Friday

    Friday: Mostly sunny, with a high near 56. Calm wind becoming west 5 to 7 mph in the afternoon.

    High: 56 °F

    Mostly Sunny

  • Friday Night

    Friday Night: A chance of rain showers before midnight, then a chance of rain and snow showers between midnight and 3am, then a chance of snow showers after 3am. Mostly cloudy, with a low around 28. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 30%.

    Low: 28 °F

    Chance
    Showers then
    Chance
    Rain/Snow

  • Saturday

    Saturday: A slight chance of snow showers before 9am, then a slight chance of rain and snow showers between 9am and noon, then a chance of rain showers after noon. Some thunder is also possible. Mostly sunny, with a high near 60. Chance of precipitation is 30%.

    High: 60 °F

    Slight Chance
    Rain/Snow
    then Chance
    Showers

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 30.

    Low: 30 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 69.

    High: 69 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 34.

    Low: 34 °F

    Partly Cloudy

Detailed Forecast

Overnight
Mostly clear, with a low around 26. Calm wind.
Thursday
A slight chance of rain and snow showers between 9am and noon, then a chance of rain showers. Some thunder is also possible. Partly sunny, with a high near 57. Light and variable wind becoming west southwest 5 to 10 mph in the morning. Winds could gust as high as 18 mph. Chance of precipitation is 40%. Little or no snow accumulation expected.
Thursday Night
Rain and snow showers likely before 3am, then a chance of snow showers. Some thunder is also possible. Mostly cloudy, with a low around 27. Southwest wind 3 to 7 mph. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.
Friday
Mostly sunny, with a high near 56. Calm wind becoming west 5 to 7 mph in the afternoon.
Friday Night
A chance of rain showers before midnight, then a chance of rain and snow showers between midnight and 3am, then a chance of snow showers after 3am. Mostly cloudy, with a low around 28. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 30%.
Saturday
A slight chance of snow showers before 9am, then a slight chance of rain and snow showers between 9am and noon, then a chance of rain showers after noon. Some thunder is also possible. Mostly sunny, with a high near 60. Chance of precipitation is 30%.
Saturday Night
Mostly clear, with a low around 30.
Sunday
Sunny, with a high near 69.
Sunday Night
Partly cloudy, with a low around 34.
Memorial Day
A chance of showers and thunderstorms after noon. Mostly sunny, with a high near 72.
Monday Night
A slight chance of showers and thunderstorms. Mostly cloudy, with a low around 35.
Tuesday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 68.
Tuesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 33.
Wednesday
A chance of showers and thunderstorms. Mostly sunny, with a high near 70.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Grand Lake CO
 40.25°N 105.82°W (Elev. 8386 ft)
Last Update:
12:46 am MDT May 21, 2026
Forecast Valid:
2am MDT May 21, 2026-6pm MDT May 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