National Weather Service Forecast for: Sioux City IA
Issued by: National Weather Service Sioux Falls, SD
Updated: 7:28 pm CDT Jun 18, 2026
 
Tonight

Tonight: Mostly clear, with a low around 53. North wind around 5 mph becoming calm in the evening.
Mostly Clear

 Juneteenth

Juneteenth: A slight chance of showers between noon and 3pm. Partly sunny, with a high near 80. Light and variable wind becoming west 5 to 10 mph in the afternoon. Chance of precipitation is 20%.
Partly Sunny
then Slight
Chance
Showers
 Friday
Night
Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 55. West wind around 5 mph becoming calm in the evening.
Decreasing
Clouds

 Saturday

Saturday: A 30 percent chance of showers after 1pm. Increasing clouds, with a high near 82. Calm wind becoming east around 5 mph in the morning.
Mostly Sunny
then Chance
Showers
 Saturday
Night
Saturday Night: Showers likely, then showers and possibly a thunderstorm after 1am. Low around 58. East wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%.
Showers

 Sunday

Sunday: Showers likely and possibly a thunderstorm before 10am, then showers likely between 10am and 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 71. East wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 70%.
Showers
Likely

 Sunday
Night
Sunday Night: A 30 percent chance of showers before 1am. Mostly cloudy, with a low around 54.
Chance
Showers

 Monday

Monday: Partly sunny, with a high near 75.
Partly Sunny

 Monday
Night
Monday Night: Partly cloudy, with a low around 55.
Partly Cloudy
Lo 53 °F Hi 80 °F Lo 55 °F Hi 82 °F Lo 58 °F Hi 71 °F Lo 54 °F Hi 75 °F Lo 55 °F

 

Tonight
 
 Mostly clear, with a low around 53. North wind around 5 mph becoming calm in the evening.
Juneteenth
 
 A slight chance of showers between noon and 3pm. Partly sunny, with a high near 80. Light and variable wind becoming west 5 to 10 mph in the afternoon. Chance of precipitation is 20%.
Friday Night
 
 Mostly cloudy, then gradually becoming mostly clear, with a low around 55. West wind around 5 mph becoming calm in the evening.
Saturday
 
 A 30 percent chance of showers after 1pm. Increasing clouds, with a high near 82. Calm wind becoming east around 5 mph in the morning.
Saturday Night
 
 Showers likely, then showers and possibly a thunderstorm after 1am. Low around 58. East wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%.
Sunday
 
 Showers likely and possibly a thunderstorm before 10am, then showers likely between 10am and 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 71. East wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 70%.
Sunday Night
 
 A 30 percent chance of showers before 1am. Mostly cloudy, with a low around 54.
Monday
 
 Partly sunny, with a high near 75.
Monday Night
 
 Partly cloudy, with a low around 55.
Tuesday
 
 Partly sunny, with a high near 78.
Tuesday Night
 
 Partly cloudy, with a low around 55.
Wednesday
 
 Mostly sunny, with a high near 79.
Wednesday Night
 
 Mostly clear, with a low around 56.
Thursday
 
 Mostly sunny, with a high near 79.

 

Forecast from NOAA-NWS for Sioux City IA.