National Weather Service Forecast for: Johnston IA
Issued by: National Weather Service Des Moines, IA
Updated: 2:36 am CDT Apr 6, 2026
 
Today

Today: A 40 percent chance of showers, mainly after 3pm.  Increasing clouds, with a high near 46. North wind 7 to 10 mph.
Mostly Cloudy
then Chance
Showers
Tonight

Tonight: A chance of rain showers before 10pm, then a slight chance of snow showers after 5am.  Cloudy, with a low around 28. North wind around 7 mph becoming east northeast after midnight.  Chance of precipitation is 30%. New snow accumulation of less than a half inch possible.
Chance
Showers then
Slight Chance
Snow Showers
Tuesday

Tuesday: A chance of snow showers before 1pm, then rain likely, possibly mixed with snow showers.  Cloudy, with a high near 40. East southeast wind 7 to 14 mph, with gusts as high as 21 mph.  Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.
Chance Snow
Showers then
Rain/Snow
Likely
Tuesday
Night
Tuesday Night: Rain likely, possibly mixed with snow showers before 7pm, then a chance of rain showers.  Mostly cloudy, with a low around 36. Southeast wind around 14 mph, with gusts as high as 24 mph.  Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.
Rain/Snow
Likely then
Chance
Showers
Wednesday

Wednesday: A chance of showers, with thunderstorms also possible after 4pm.  Partly sunny, with a high near 67. Windy, with a south southwest wind 16 to 22 mph, with gusts as high as 33 mph.  Chance of precipitation is 50%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
Showers and
Windy
Wednesday
Night
Wednesday Night: Showers likely and possibly a thunderstorm before 1am, then a chance of showers.  Mostly cloudy, with a low around 46. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Showers
Likely

Thursday

Thursday: Showers likely, mainly after 1pm.  Mostly cloudy, with a high near 61. Chance of precipitation is 60%.
Showers
Likely

Thursday
Night
Thursday Night: A 50 percent chance of showers.  Mostly cloudy, with a low around 43.
Chance
Showers

Friday

Friday: A 30 percent chance of showers after 1pm.  Partly sunny, with a high near 61.
Partly Sunny
then Chance
Showers
Hi 46 °F Lo 28 °F Hi 40 °F Lo 36 °F Hi 67 °F Lo 46 °F Hi 61 °F Lo 43 °F Hi 61 °F

 

Today
 
A 40 percent chance of showers, mainly after 3pm. Increasing clouds, with a high near 46. North wind 7 to 10 mph.
Tonight
 
A chance of rain showers before 10pm, then a slight chance of snow showers after 5am. Cloudy, with a low around 28. North wind around 7 mph becoming east northeast after midnight. Chance of precipitation is 30%. New snow accumulation of less than a half inch possible.
Tuesday
 
A chance of snow showers before 1pm, then rain likely, possibly mixed with snow showers. Cloudy, with a high near 40. East southeast wind 7 to 14 mph, with gusts as high as 21 mph. Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.
Tuesday Night
 
Rain likely, possibly mixed with snow showers before 7pm, then a chance of rain showers. Mostly cloudy, with a low around 36. Southeast wind around 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.
Wednesday
 
A chance of showers, with thunderstorms also possible after 4pm. Partly sunny, with a high near 67. Windy, with a south southwest wind 16 to 22 mph, with gusts as high as 33 mph. Chance of precipitation is 50%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
 
Showers likely and possibly a thunderstorm before 1am, then a chance of showers. Mostly cloudy, with a low around 46. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday
 
Showers likely, mainly after 1pm. Mostly cloudy, with a high near 61. Chance of precipitation is 60%.
Thursday Night
 
A 50 percent chance of showers. Mostly cloudy, with a low around 43.
Friday
 
A 30 percent chance of showers after 1pm. Partly sunny, with a high near 61.
Friday Night
 
A 50 percent chance of showers. Mostly cloudy, with a low around 46.
Saturday
 
Showers likely. Mostly cloudy, with a high near 65. Chance of precipitation is 60%.
Saturday Night
 
Showers likely. Cloudy, with a low around 56. Chance of precipitation is 60%.
Sunday
 
Showers likely. Mostly cloudy, with a high near 75. Breezy. Chance of precipitation is 70%.

 

Forecast from NOAA-NWS for Johnston IA.