Waterloo, IA Weather & Growing Conditions
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
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 79°F | Patchy Fog | 8 mph SW | 57% |
| Tonight | 60°F | Chance Showers And Thunderstorms | 8 to 12 mph N | 38% |
| Sunday | 66°F | Chance Rain Showers then Chance Drizzle | 12 to 15 mph NE | 36% |
| Sunday Night | 54°F | Chance Rain Showers | 14 mph ENE | 40% |
| Monday | 63°F | Chance Rain Showers | 14 mph ENE | 42% |
| Monday Night | 49°F | Chance Rain Showers | 8 to 12 mph NE | 42% |
| Tuesday | 61°F | Slight Chance Rain Showers then Partly Sunny | 10 mph ENE | 19% |
| Tuesday Night | 45°F | Mostly Clear | 5 to 8 mph ENE | 3% |
| Wednesday | 66°F | Sunny | 6 mph ENE | 1% |
| Wednesday Night | 50°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). 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 (7.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.