National Weather Service Forecast for: Mason City IA
Issued by: National Weather Service Des Moines, IA
Updated: 10:43 pm CDT Jun 29, 2026
 
Overnight

Overnight: A 40 percent chance of showers and thunderstorms, mainly after 2am. Mostly cloudy, with a low around 75. South southwest wind 10 to 15 mph, with gusts as high as 23 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
Showers
 Tuesday

Tuesday: A 10 percent chance of showers before 7am. Mostly sunny, with a high near 93. Heat index values as high as 100. Southwest wind 8 to 14 mph, with gusts as high as 23 mph.
Slight Chance
Showers then
Mostly Sunny
 Tuesday
Night
Tuesday Night: A chance of showers and thunderstorms before 2am, then showers likely and possibly a thunderstorm after 4am. Mostly cloudy, with a low around 72. South southwest wind 7 to 9 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Partly Cloudy
then Showers
Likely
 Wednesday

Wednesday: Showers likely and possibly a thunderstorm before 1pm. Mostly sunny, with a high near 90. Breezy, with a south southwest wind 10 to 17 mph, with gusts as high as 28 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Showers
Likely and
Breezy
 Wednesday
Night
Wednesday Night: Showers and possibly a thunderstorm. Low around 72. South southwest wind 11 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Showers

 Thursday

Thursday: A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 89. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
T-storms
 Thursday
Night
Thursday Night: Showers likely and possibly a thunderstorm. Partly cloudy, with a low around 70. Chance of precipitation is 70%.
Showers
Likely
 Friday

Friday: A 30 percent chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 88.
Chance
T-storms
 Friday
Night
Friday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 69.
Chance
T-storms
Lo 75 °F Hi 93 °F Lo 72 °F Hi 90 °F Lo 72 °F Hi 89 °F Lo 70 °F Hi 88 °F Lo 69 °F

Hazardous Weather Outlook
Extreme Heat Warning
 

Overnight
 
 A 40 percent chance of showers and thunderstorms, mainly after 2am. Mostly cloudy, with a low around 75. South southwest wind 10 to 15 mph, with gusts as high as 23 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tuesday
 
 A 10 percent chance of showers before 7am. Mostly sunny, with a high near 93. Heat index values as high as 100. Southwest wind 8 to 14 mph, with gusts as high as 23 mph.
Tuesday Night
 
 A chance of showers and thunderstorms before 2am, then showers likely and possibly a thunderstorm after 4am. Mostly cloudy, with a low around 72. South southwest wind 7 to 9 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday
 
 Showers likely and possibly a thunderstorm before 1pm. Mostly sunny, with a high near 90. Breezy, with a south southwest wind 10 to 17 mph, with gusts as high as 28 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
 
 Showers and possibly a thunderstorm. Low around 72. South southwest wind 11 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday
 
 A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 89. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Thursday Night
 
 Showers likely and possibly a thunderstorm. Partly cloudy, with a low around 70. Chance of precipitation is 70%.
Friday
 
 A 30 percent chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 88.
Friday Night
 
 A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 69.
Independence Day
 
 A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 88.
Saturday Night
 
 Showers and thunderstorms likely. Partly cloudy, with a low around 69. Chance of precipitation is 60%.
Sunday
 
 A 30 percent chance of showers. Partly sunny, with a high near 84.
Sunday Night
 
 Partly cloudy, with a low around 64.
Monday
 
 Sunny, with a high near 83.

 

Forecast from NOAA-NWS for Mason City IA.