NWS Forecast for Waterloo IA

National Weather Service Forecast for: Waterloo IA
Issued by: National Weather Service Des Moines, IA

Updated: 3:37 am CDT Jun 22, 2026

Today Areas Fog then Mostly Sunny	Tonight Partly Cloudy	Tuesday Increasing Clouds	Tuesday Night Slight Chance T-storms then Chance T-storms	Wednesday Chance T-storms	Wednesday Night Mostly Clear	Thursday Mostly Sunny	Thursday Night Mostly Clear	Friday Mostly Sunny
Hi 78 °F	Lo 55 °F	Hi 79 °F	Lo 61 °F	Hi 81 °F	Lo 57 °F	Hi 77 °F	Lo 56 °F	Hi 78 °F

Hazardous Weather Outlook
Dense Fog Advisory

Today	Areas of fog before 9am. Otherwise, mostly sunny, with a high near 78. Calm wind becoming northeast around 5 mph in the afternoon.
Tonight	Partly cloudy, with a low around 55. Light east wind.
Tuesday	Increasing clouds, with a high near 79. Calm wind becoming south 5 to 9 mph in the afternoon.
Tuesday Night	A 50 percent chance of showers and thunderstorms, mainly after 1am. Mostly cloudy, with a low around 61. South wind 6 to 8 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday	A 30 percent chance of showers and thunderstorms, mainly before 7am. Mostly sunny, with a high near 81. West wind 6 to 11 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night	Mostly clear, with a low around 57.
Thursday	Mostly sunny, with a high near 77.
Thursday Night	Mostly clear, with a low around 56.
Friday	Mostly sunny, with a high near 78.
Friday Night	Mostly cloudy, with a low around 60.
Saturday	Mostly sunny, with a high near 82.
Saturday Night	A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 67. Breezy.
Sunday	Mostly sunny, with a high near 89. Breezy.

Forecast from NOAA-NWS for Waterloo IA.