National Weather Service Forecast for: Johnston IA
Issued by: National Weather Service Des Moines, IA
Updated: 5:01 pm CST Dec 17, 2025
 
Tonight

Tonight: Rain, mainly after midnight. Low around 36. South southeast wind around 14 mph becoming west after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Mostly Cloudy
then Rain

 Thursday

Thursday: A chance of rain and snow before 4pm, then a slight chance of snow between 4pm and 5pm. Cloudy through mid morning, then becoming mostly sunny, with a temperature falling to around 21 by 5pm. Wind chill values as low as 5. Windy, with a west wind 15 to 20 mph increasing to 23 to 28 mph in the afternoon. Winds could gust as high as 44 mph. Chance of precipitation is 30%. Little or no snow accumulation expected.
Windy. Chance
Rain then
Slight Chance
Snow
 Thursday
Night
Thursday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 13. Wind chill values as low as zero. Windy, with a northwest wind 18 to 23 mph decreasing to 6 to 11 mph after midnight. Winds could gust as high as 39 mph.
Mostly Cloudy
and Windy
then Mostly
Clear
 Friday

Friday: Mostly sunny, with a high near 35. Wind chill values as low as 5. West northwest wind 5 to 13 mph becoming south southeast in the afternoon. Winds could gust as high as 22 mph.
Mostly Sunny

 Friday
Night
Friday Night: Mostly cloudy, with a low around 29. South wind 9 to 13 mph, with gusts as high as 21 mph.
Mostly Cloudy

 Saturday

Saturday: Partly sunny, with a high near 40.
Partly Sunny

 Saturday
Night
Saturday Night: Partly cloudy, with a low around 21.
Partly Cloudy

 Sunday

Sunday: Mostly sunny, with a high near 38.
Mostly Sunny

 Sunday
Night
Sunday Night: Mostly cloudy, with a low around 28.
Mostly Cloudy
Lo 36 °F Hi 39 °F⇓ Lo 13 °F Hi 35 °F Lo 29 °F Hi 40 °F Lo 21 °F Hi 38 °F Lo 28 °F

Wind Advisory
 

Tonight
 
 Rain, mainly after midnight. Low around 36. South southeast wind around 14 mph becoming west after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Thursday
 
 A chance of rain and snow before 4pm, then a slight chance of snow between 4pm and 5pm. Cloudy through mid morning, then becoming mostly sunny, with a temperature falling to around 21 by 5pm. Wind chill values as low as 5. Windy, with a west wind 15 to 20 mph increasing to 23 to 28 mph in the afternoon. Winds could gust as high as 44 mph. Chance of precipitation is 30%. Little or no snow accumulation expected.
Thursday Night
 
 Mostly cloudy, then gradually becoming mostly clear, with a low around 13. Wind chill values as low as zero. Windy, with a northwest wind 18 to 23 mph decreasing to 6 to 11 mph after midnight. Winds could gust as high as 39 mph.
Friday
 
 Mostly sunny, with a high near 35. Wind chill values as low as 5. West northwest wind 5 to 13 mph becoming south southeast in the afternoon. Winds could gust as high as 22 mph.
Friday Night
 
 Mostly cloudy, with a low around 29. South wind 9 to 13 mph, with gusts as high as 21 mph.
Saturday
 
 Partly sunny, with a high near 40.
Saturday Night
 
 Partly cloudy, with a low around 21.
Sunday
 
 Mostly sunny, with a high near 38.
Sunday Night
 
 Mostly cloudy, with a low around 28.
Monday
 
 Partly sunny, with a high near 45.
Monday Night
 
 Mostly cloudy, with a low around 34.
Tuesday
 
 Partly sunny, with a high near 46.
Tuesday Night
 
 Mostly cloudy, with a low around 28.
Wednesday
 
 Partly sunny, with a high near 42.

 

Forecast from NOAA-NWS for Johnston IA.