National Weather Service Forecast for: Grinnell IA
Issued by: National Weather Service Des Moines, IA
Updated: 10:33 am CDT May 20, 2025
Grinnell
 
This
Afternoon
This Afternoon: A 40 percent chance of showers and thunderstorms.  Mostly cloudy, with a steady temperature around 62. West wind 7 to 11 mph.  New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
T-storms
Tonight

Tonight: A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers between 7pm and 8pm.  Mostly cloudy, with a low around 44. West northwest wind around 14 mph, with gusts as high as 22 mph.  Chance of precipitation is 20%.
Slight Chance
T-storms then
Mostly Cloudy
Wednesday

Wednesday: A 30 percent chance of showers, mainly after noon.  Partly sunny, with a high near 57. Breezy, with a west northwest wind 16 to 18 mph, with gusts as high as 25 mph.
Chance
Showers and
Breezy
Wednesday
Night
Wednesday Night: A 40 percent chance of showers before 1am.  Mostly cloudy, with a low around 43. Northwest wind 10 to 14 mph, with gusts as high as 21 mph.
Chance
Showers
Thursday

Thursday: Partly sunny, with a high near 62. North northwest wind 10 to 13 mph, with gusts as high as 20 mph.
Partly Sunny

Thursday
Night
Thursday Night: Mostly clear, with a low around 42.
Mostly Clear

Friday

Friday: Mostly sunny, with a high near 67.
Mostly Sunny

Friday
Night
Friday Night: A 20 percent chance of showers.  Mostly cloudy, with a low around 46.
Slight Chance
Showers
Saturday

Saturday: A 30 percent chance of showers after 1pm.  Partly sunny, with a high near 66.
Mostly Sunny
then Chance
Showers
Hi 62 °F Lo 44 °F Hi 57 °F Lo 43 °F Hi 62 °F Lo 42 °F Hi 67 °F Lo 46 °F Hi 66 °F

Hazardous Weather Outlook
 

This Afternoon
 
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a steady temperature around 62. West wind 7 to 11 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tonight
 
A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers between 7pm and 8pm. Mostly cloudy, with a low around 44. West northwest wind around 14 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.
Wednesday
 
A 30 percent chance of showers, mainly after noon. Partly sunny, with a high near 57. Breezy, with a west northwest wind 16 to 18 mph, with gusts as high as 25 mph.
Wednesday Night
 
A 40 percent chance of showers before 1am. Mostly cloudy, with a low around 43. Northwest wind 10 to 14 mph, with gusts as high as 21 mph.
Thursday
 
Partly sunny, with a high near 62. North northwest wind 10 to 13 mph, with gusts as high as 20 mph.
Thursday Night
 
Mostly clear, with a low around 42.
Friday
 
Mostly sunny, with a high near 67.
Friday Night
 
A 20 percent chance of showers. Mostly cloudy, with a low around 46.
Saturday
 
A 30 percent chance of showers after 1pm. Partly sunny, with a high near 66.
Saturday Night
 
A 40 percent chance of showers. Mostly cloudy, with a low around 47.
Sunday
 
A 40 percent chance of showers. Partly sunny, with a high near 66.
Sunday Night
 
A 50 percent chance of showers. Mostly cloudy, with a low around 48.
Memorial Day
 
A 40 percent chance of showers. Partly sunny, with a high near 66.

 

Forecast from NOAA-NWS for Grinnell IA.