National Weather Service Forecast for: Altoona IA
Issued by: National Weather Service Des Moines, IA
Updated: 1:26 am CDT Jun 30, 2026
 
Overnight

Overnight: Partly cloudy, with a low around 76. South southwest wind around 11 mph, with gusts as high as 22 mph.
Partly Cloudy

 Tuesday

Tuesday: Mostly sunny, with a high near 94. Heat index values as high as 105. Breezy, with a south southwest wind 9 to 17 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. Mostly cloudy, with a low around 74. South southwest wind 11 to 13 mph, with gusts as high as 22 mph. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
T-storms then
Mostly Cloudy
 Wednesday

Wednesday: Mostly sunny, with a high near 92. Breezy, with a south southwest wind 11 to 17 mph, with gusts as high as 26 mph.
Sunny then
Mostly Sunny
and Breezy
 Wednesday
Night
Wednesday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74. South southwest wind 11 to 15 mph, with gusts as high as 26 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
Showers then
Chance
T-storms
 Thursday

Thursday: A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 91. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Chance
T-storms

 Thursday
Night
Thursday Night: A 50 percent chance of showers and thunderstorms, mainly after 1am. Partly cloudy, with a low around 72.
Chance
T-storms

 Friday

Friday: A 30 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 92.
Chance
T-storms

 Friday
Night
Friday Night: A chance of showers, with thunderstorms also possible after 1am. Partly cloudy, with a low around 71. Chance of precipitation is 30%.
Chance
Showers then
Chance
T-storms
Lo 76 °F Hi 94 °F Lo 74 °F Hi 92 °F Lo 74 °F Hi 91 °F Lo 72 °F Hi 92 °F Lo 71 °F

Hazardous Weather Outlook
Extreme Heat Warning
 

Overnight
 
 Partly cloudy, with a low around 76. South southwest wind around 11 mph, with gusts as high as 22 mph.
Tuesday
 
 Mostly sunny, with a high near 94. Heat index values as high as 105. Breezy, with a south southwest wind 9 to 17 mph, with gusts as high as 25 mph.
Tuesday Night
 
 A 30 percent chance of showers and thunderstorms, mainly before 10pm. Mostly cloudy, with a low around 74. South southwest wind 11 to 13 mph, with gusts as high as 22 mph. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday
 
 Mostly sunny, with a high near 92. Breezy, with a south southwest wind 11 to 17 mph, with gusts as high as 26 mph.
Wednesday Night
 
 A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74. South southwest wind 11 to 15 mph, with gusts as high as 26 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Thursday
 
 A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 91. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Thursday Night
 
 A 50 percent chance of showers and thunderstorms, mainly after 1am. Partly cloudy, with a low around 72.
Friday
 
 A 30 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 92.
Friday Night
 
 A chance of showers, with thunderstorms also possible after 1am. Partly cloudy, with a low around 71. Chance of precipitation is 30%.
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
 
 A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 87.
Sunday Night
 
 A 30 percent chance of showers. Partly cloudy, with a low around 67.
Monday
 
 Mostly sunny, with a high near 87.

 

Forecast from NOAA-NWS for Altoona IA.