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

Dangerous Heat and Possible Flooding

Dangerous heat will persist across the Southwest U.S. through Saturday with daytime highs of 110-115°F. Extreme Heat Warnings remain in effect. Dangerous heat will build across the southern Plains again beginning this weekend. Heavy to excessive rain over the Carolinas Friday may lead to isolated areas of flash flooding. Read More >

Hazardous Weather Conditions

Current conditions at

Oelwein Municipal Airport (KOLZ)

Lat: 42.68°NLon: 91.98°WElev: 1070ft.

Fair

81°F

27°C

Humidity 48%
Wind Speed NW 5 mph
Barometer 30.10 in
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Heat Index81°F (27°C)
Last update 28 Aug 4:55 pm CDT
Extended Forecast for

Sumner IA

  • Tonight

    Tonight: A 30 percent chance of showers, mainly after 5am. Mostly cloudy, with a low around 64. South wind 5 to 11 mph, with gusts as high as 18 mph. New precipitation amounts of less than a tenth of an inch possible.

    Low: 64 °F

    Partly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: Showers likely, mainly before 11am. Cloudy, then gradually becoming mostly sunny, with a high near 79. Windy, with a south wind 13 to 21 mph, with gusts as high as 31 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 79 °F

    Showers
    Likely and
    Breezy then
    Chance
    Showers and
    Windy

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 69. Breezy, with a south wind 13 to 18 mph, with gusts as high as 29 mph.

    Low: 69 °F

    Partly Cloudy
    and Breezy
    then Partly
    Cloudy

  • Sunday

    Sunday: A slight chance of showers before 10am, then a slight chance of showers and thunderstorms between 10am and 1pm. Mostly sunny, with a high near 86. South southwest wind around 15 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.

    High: 86 °F

    Slight Chance
    T-storms

  • Sunday Night

    Sunday Night: A 20 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 72. South wind 10 to 13 mph, with gusts as high as 20 mph.

    Low: 72 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Monday

    Monday: Partly sunny, with a high near 88.

    High: 88 °F

    Partly Sunny

  • Monday Night

    Monday Night: A 40 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 71.

    Low: 71 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 87.

    High: 87 °F

    Slight Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70.

    Low: 70 °F

    Chance
    T-storms

Detailed Forecast

Tonight
A 30 percent chance of showers, mainly after 5am. Mostly cloudy, with a low around 64. South wind 5 to 11 mph, with gusts as high as 18 mph. New precipitation amounts of less than a tenth of an inch possible.
Saturday
Showers likely, mainly before 11am. Cloudy, then gradually becoming mostly sunny, with a high near 79. Windy, with a south wind 13 to 21 mph, with gusts as high as 31 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.
Saturday Night
Partly cloudy, with a low around 69. Breezy, with a south wind 13 to 18 mph, with gusts as high as 29 mph.
Sunday
A slight chance of showers before 10am, then a slight chance of showers and thunderstorms between 10am and 1pm. Mostly sunny, with a high near 86. South southwest wind around 15 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.
Sunday Night
A 20 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 72. South wind 10 to 13 mph, with gusts as high as 20 mph.
Monday
Partly sunny, with a high near 88.
Monday Night
A 40 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 71.
Tuesday
A 20 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 87.
Tuesday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70.
Wednesday
Mostly sunny, with a high near 87.
Wednesday Night
Mostly clear, with a low around 70.
Thursday
Mostly sunny, with a high near 87.
Thursday Night
A 30 percent chance of showers. Partly cloudy, with a low around 69.
Friday
Mostly sunny, with a high near 87.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Sumner IA
 42.85°N 92.1°W
Last Update:
2:21 pm CDT Aug 28, 2026
Forecast Valid:
5pm CDT Aug 28, 2026-6pm CDT Sep 4, 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