Waterloo, IA Weather & Growing Conditions
Tonight
48°F
Slight Chance Rain Showers
A slight chance of rain showers before 5am. Cloudy. Low around 48, with temperatures rising to around 52 overnight. South southwest wind around 10 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 48°F | Slight Chance Rain Showers | 10 mph SSW | 24% |
| Wednesday | 54°F | Chance Rain Showers | 12 to 16 mph WSW | 41% |
| Wednesday Night | 43°F | Rain Showers Likely | 15 mph WSW | 60% |
| Thursday | 52°F | Rain Showers Likely | 13 mph NW | 69% |
| Thursday Night | 38°F | Mostly Cloudy | 12 mph N | 14% |
| Friday | 50°F | Partly Sunny | 5 to 10 mph N | 2% |
| Friday Night | 32°F | Partly Cloudy | 3 mph NW | 0% |
| Saturday | 54°F | Mostly Sunny | 1 to 6 mph WSW | 2% |
| Saturday Night | 36°F | Mostly Clear | 5 mph W | 4% |
| Sunday | 59°F | Sunny | 5 to 9 mph WNW | 7% |
| Sunday Night | 37°F | Mostly Clear | 6 mph SW | 2% |
| Monday | 62°F | Mostly Sunny | 6 to 12 mph SW | 0% |
| Monday Night | 40°F | Mostly Clear | 7 mph WNW | 0% |
| Tuesday | 60°F | Sunny | 7 mph WNW | 0% |
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 Nov 4, 2026.