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Waterloo, IA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Waterloo, a city in Black Hawk County, Iowa.

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. Southeast wind around 7 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Waterloo

WhenTempForecastWindPrecip
This Afternoon 76°F Chance Showers And Thunderstorms 7 mph SE 58%
Tonight 60°F Chance Showers And Thunderstorms 6 to 12 mph NNE 46%
Sunday 67°F Chance Rain Showers 14 mph NE 42%
Sunday Night 54°F Slight Chance Drizzle then Chance Rain Showers 14 mph ENE 45%
Monday 61°F Rain Showers Likely 14 mph ENE 65%
Monday Night 50°F Rain Showers Likely 8 to 12 mph NE 65%
Tuesday 61°F Chance Rain Showers then Partly Sunny 9 mph NE 32%
Tuesday Night 47°F Partly Cloudy 7 mph NE 3%
Wednesday 65°F Mostly Sunny 6 mph ENE 1%
Wednesday Night 51°F Partly Cloudy 5 mph E 3%
Thursday 67°F Partly Sunny 3 mph ESE 13%
Thursday Night 56°F Slight Chance Rain Showers 3 mph ESE 22%
Friday 70°F Slight Chance Rain Showers then Partly Sunny 5 mph E 16%
Friday Night 57°F Partly Cloudy 3 mph E 10%

Forecast source: National Weather Service (api.weather.gov) for Waterloo (42.492, -92.352). Updated through the day.

Growing snapshot for Waterloo

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

More local growing data for Waterloo: nearby ZIP 50702 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Waterloo Muni Ap, Ia (7.8 mi from Waterloo). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.