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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.

Today
79°F
Patchy Fog
Patchy fog and showers and thunderstorms likely before 1pm, then a chance of showers and thunderstorms between 1pm and 3pm, then showers and thunderstorms likely between 3pm and 4pm, then a chance of showers and thunderstorms. Mostly cloudy. High near 79, with temperatures falling to around 76 in the afternoon. Southwest wind around 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.

7-day forecast for Waterloo

WhenTempForecastWindPrecip
Today 79°F Patchy Fog 8 mph SW 57%
Tonight 60°F Chance Showers And Thunderstorms 10 mph N 37%
Sunday 67°F Chance Rain Showers then Chance Drizzle 14 mph NE 35%
Sunday Night 55°F Chance Rain Showers 13 mph ENE 40%
Monday 63°F Chance Rain Showers 14 mph ENE 43%
Monday Night 49°F Chance Rain Showers 8 to 12 mph NE 43%
Tuesday 61°F Slight Chance Rain Showers then Partly Sunny 9 mph ENE 17%
Tuesday Night 46°F Mostly Clear 7 mph ENE 3%
Wednesday 66°F Sunny 6 mph ENE 1%
Wednesday Night 51°F Partly Cloudy 5 mph ENE 3%
Thursday 67°F Partly Sunny 5 mph E 8%
Thursday Night 53°F Partly Cloudy 3 mph E 6%
Friday 69°F Mostly Sunny 2 to 6 mph ESE 5%
Friday Night 54°F Partly Cloudy 5 mph ESE 8%

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.