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Waterloo, IA Weather & Growing Conditions

This Afternoon
75°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Mostly cloudy, with a high near 75. Southeast wind around 6 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 75°F Showers And Thunderstorms Likely 6 mph SE 61%
Tonight 60°F Chance Showers And Thunderstorms 6 to 14 mph NNE 51%
Sunday 66°F Chance Rain Showers 16 mph NE 37%
Sunday Night 53°F Slight Chance Drizzle then Chance Rain Showers 16 mph ENE 41%
Monday 61°F Rain Showers Likely 16 mph ENE 64%
Monday Night 49°F Rain Showers Likely 14 mph NE 64%
Tuesday 61°F Chance Rain Showers then Partly Sunny 12 mph NE 37%
Tuesday Night 46°F Partly Cloudy 8 mph NE 3%
Wednesday 64°F Mostly Sunny 8 mph ENE 1%
Wednesday Night 50°F Partly Cloudy 6 mph E 3%
Thursday 66°F Partly Sunny 5 mph ESE 12%
Thursday Night 55°F Slight Chance Rain Showers 3 mph ESE 22%
Friday 70°F Slight Chance Rain Showers then Partly Sunny 6 mph E 16%
Friday Night 55°F Partly Cloudy 5 mph E 10%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Waterloo, IA

Last spring frost
Apr 27
First fall frost
Oct 10
Growing season
165 days
Hardiness zone
5a

Explore more for Waterloo, IA: full frost dates · planting calendar · Iowa frost dates

Climate data from the nearest NOAA station, Waterloo Muni Ap, Ia (9.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.