National Weather Service Forecast for: Marshalltown IA
Issued by: National Weather Service Des Moines, IA
Updated: 3:16 am CDT Jun 30, 2026
 
Overnight

Overnight: Partly cloudy, with a steady temperature around 79. South southwest wind around 11 mph.
Partly Cloudy

 Tuesday

Tuesday: Mostly sunny, with a high near 95. Heat index values as high as 105. Breezy, with a south southwest wind 11 to 18 mph, with gusts as high as 25 mph.
Mostly Sunny
and Breezy

 Tuesday
Night
Tuesday Night: A 30 percent chance of showers and thunderstorms, mainly before 10pm. Partly cloudy, with a low around 74. South southwest wind 10 to 13 mph, with gusts as high as 20 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
T-storms

 Wednesday

Wednesday: Mostly sunny, with a high near 94. Heat index values as high as 100. Breezy, with a south southwest wind 10 to 16 mph, with gusts as high as 26 mph.
Sunny then
Mostly Sunny
and Breezy
 Wednesday
Night
Wednesday Night: A 50 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74. South southwest wind 10 to 15 mph, with gusts as high as 25 mph. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Chance
T-storms

 Thursday

Thursday: A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 92. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
Showers then
Chance
T-storms
 Thursday
Night
Thursday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 72. Chance of precipitation is 60%.
Chance
T-storms then
Showers
Likely
 Friday

Friday: A 30 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 93.
Chance
T-storms

 Friday
Night
Friday Night: A chance of showers and thunderstorms. Partly cloudy, with a low around 71. Chance of precipitation is 40%.
Chance
T-storms
Lo 79 °F Hi 95 °F Lo 74 °F Hi 94 °F Lo 74 °F Hi 92 °F Lo 72 °F Hi 93 °F Lo 71 °F

Hazardous Weather Outlook
Extreme Heat Warning
 

Overnight
 
 Partly cloudy, with a steady temperature around 79. South southwest wind around 11 mph.
Tuesday
 
 Mostly sunny, with a high near 95. Heat index values as high as 105. Breezy, with a south southwest wind 11 to 18 mph, with gusts as high as 25 mph.
Tuesday Night
 
 A 30 percent chance of showers and thunderstorms, mainly before 10pm. Partly cloudy, with a low around 74. South southwest wind 10 to 13 mph, with gusts as high as 20 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday
 
 Mostly sunny, with a high near 94. Heat index values as high as 100. Breezy, with a south southwest wind 10 to 16 mph, with gusts as high as 26 mph.
Wednesday Night
 
 A 50 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74. South southwest wind 10 to 15 mph, with gusts as high as 25 mph. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday
 
 A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 92. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Thursday Night
 
 A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 72. Chance of precipitation is 60%.
Friday
 
 A 30 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 93.
Friday Night
 
 A chance of showers and thunderstorms. Partly cloudy, with a low around 71. Chance of precipitation is 40%.
Independence Day
 
 A 40 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 91.
Saturday Night
 
 A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 69.
Sunday
 
 Mostly sunny, with a high near 89.
Sunday Night
 
 A 30 percent chance of showers. Partly cloudy, with a low around 66.
Monday
 
 Mostly sunny, with a high near 88.

 

Forecast from NOAA-NWS for Marshalltown IA.