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Waterloo, IA Weather & Growing Conditions

This Afternoon
76°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 3pm, then showers and thunderstorms likely. Mostly cloudy. High near 76, with temperatures falling to around 74 in the afternoon. East southeast wind around 7 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 76°F Chance Showers And Thunderstorms 7 mph ESE 58%
Tonight 60°F Chance Showers And Thunderstorms 6 to 13 mph NNE 45%
Sunday 66°F Chance Rain Showers 15 mph NE 44%
Sunday Night 54°F Slight Chance Drizzle then Chance Rain Showers 15 mph ENE 46%
Monday 61°F Rain Showers Likely 15 mph ENE 66%
Monday Night 49°F Rain Showers Likely 9 to 13 mph NE 66%
Tuesday 61°F Chance Rain Showers then Partly Sunny 10 mph NE 32%
Tuesday Night 47°F Partly Cloudy 5 to 8 mph NE 3%
Wednesday 64°F Mostly Sunny 7 mph ENE 1%
Wednesday Night 50°F Partly Cloudy 5 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 5 mph E 17%
Friday Night 56°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.