National Weather Service Forecast for: Johnston IA
Issued by: National Weather Service Des Moines, IA
Updated: 10:46 pm CST Dec 4, 2025
 
Overnight

Overnight: Mostly cloudy, with a steady temperature around 17. Wind chill values as low as 5. South wind around 9 mph.
Mostly Cloudy

 Friday

Friday: Partly sunny, with a high near 34. Wind chill values as low as 5. South wind 7 to 9 mph becoming west in the afternoon.
Partly Sunny

 Friday
Night
Friday Night: Mostly cloudy, with a low around 19. West wind 5 to 9 mph becoming light and variable after midnight. Winds could gust as high as 18 mph.
Mostly Cloudy

 Saturday

Saturday: A 30 percent chance of snow after noon. Mostly cloudy, with a high near 28. Calm wind becoming east southeast 5 to 9 mph in the morning. Little or no snow accumulation expected.
Partly Sunny
then Chance
Snow
 Saturday
Night
Saturday Night: Snow, mainly before midnight. Low around 12. East southeast wind around 9 mph becoming north northeast after midnight. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.
Snow then
Chance Snow
 Sunday

Sunday: Partly sunny, with a high near 18.
Partly Sunny

 Sunday
Night
Sunday Night: Mostly cloudy, with a low around -4.
Mostly Cloudy

 Monday

Monday: Partly sunny, with a high near 27.
Partly Sunny

 Monday
Night
Monday Night: Mostly cloudy, with a low around 19.
Mostly Cloudy
Lo 17 °F Hi 34 °F Lo 19 °F Hi 28 °F Lo 12 °F Hi 18 °F Lo -4 °F Hi 27 °F Lo 19 °F

 

Overnight
 
 Mostly cloudy, with a steady temperature around 17. Wind chill values as low as 5. South wind around 9 mph.
Friday
 
 Partly sunny, with a high near 34. Wind chill values as low as 5. South wind 7 to 9 mph becoming west in the afternoon.
Friday Night
 
 Mostly cloudy, with a low around 19. West wind 5 to 9 mph becoming light and variable after midnight. Winds could gust as high as 18 mph.
Saturday
 
 A 30 percent chance of snow after noon. Mostly cloudy, with a high near 28. Calm wind becoming east southeast 5 to 9 mph in the morning. Little or no snow accumulation expected.
Saturday Night
 
 Snow, mainly before midnight. Low around 12. East southeast wind around 9 mph becoming north northeast after midnight. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.
Sunday
 
 Partly sunny, with a high near 18.
Sunday Night
 
 Mostly cloudy, with a low around -4.
Monday
 
 Partly sunny, with a high near 27.
Monday Night
 
 Mostly cloudy, with a low around 19.
Tuesday
 
 Partly sunny, with a high near 35.
Tuesday Night
 
 A 30 percent chance of rain. Cloudy, with a low around 24.
Wednesday
 
 Mostly cloudy, with a high near 34.
Wednesday Night
 
 Mostly cloudy, with a low around 11.
Thursday
 
 Mostly cloudy, with a high near 25.

 

Forecast from NOAA-NWS for Johnston IA.