Hot-summer humid continental climate
Climate Waterloo - Illinois
Annual high65ºF
Annual low47ºF
Precipitation43.18 inch
| Month | HighºF | LowºF | Precipinch | Snowinch |
|---|---|---|---|---|
| Jan | 39 | 23 | 2.45 | 4 |
| Feb | 44 | 27 | 2.53 | 3 |
| Mar | 55 | 36 | 3.30 | 1 |
| Apr | 67 | 46 | 4.09 | 0 |
| May | 76 | 55 | 4.93 | 0 |
| Jun | 84 | 65 | 4.22 | 0 |
| Jul | 88 | 68 | 4.22 | 0 |
| Aug | 87 | 66 | 3.11 | 0 |
| Sep | 80 | 59 | 3.69 | 0 |
| Oct | 68 | 48 | 3.57 | 0 |
| Nov | 56 | 38 | 3.75 | 0 |
| Dec | 42 | 27 | 3.32 | 3 |
- JanHigh 39ºFLow 23ºFPrecip 2.45 inch
- FebHigh 44ºFLow 27ºFPrecip 2.53 inch
- MarHigh 55ºFLow 36ºFPrecip 3.30 inch
- AprHigh 67ºFLow 46ºFPrecip 4.09 inch
- MayHigh 76ºFLow 55ºFPrecip 4.93 inch
- JunHigh 84ºFLow 65ºFPrecip 4.22 inch
- JulHigh 88ºFLow 68ºFPrecip 4.22 inch
- AugHigh 87ºFLow 66ºFPrecip 3.11 inch
- SepHigh 80ºFLow 59ºFPrecip 3.69 inch
- OctHigh 68ºFLow 48ºFPrecip 3.57 inch
- NovHigh 56ºFLow 38ºFPrecip 3.75 inch
- DecHigh 42ºFLow 27ºFPrecip 3.32 inch
Climate summary
What is the average weather in Waterloo, Illinois?
Waterloo experiences a humid continental climate, marked by very large seasonal temperature contrasts. Summers are hot, while winters are cold and bring regular snowfall. Precipitation is fairly wet overall, spread relatively evenly through the year, with winter moisture often arriving as snow.
Waterloo weather averages
Annual high65ºF
Annual low47ºF
Precipitation43.18 inch
Snowfall11 inch
Daily normals Waterloo - Illinois - January
| Day | HighºF | LowºF | Prec/ | Prec/ | Snow/ | Snow/ |
|---|---|---|---|---|---|---|
| Jan 1 | 39.1 | 23.7 | 0.08 | 0.08 | 0.12 | 0.12 |
| Jan 2 | 39.0 | 23.6 | 0.20 | 0.20 | 0.20 | 0.20 |
| Jan 3 | 38.9 | 23.6 | 0.28 | 0.28 | 0.31 | 0.31 |
| Jan 4 | 38.9 | 23.5 | 0.35 | 0.35 | 0.39 | 0.39 |
| Jan 5 | 38.8 | 23.4 | 0.43 | 0.43 | 0.51 | 0.51 |
| Jan 6 | 38.8 | 23.4 | 0.51 | 0.51 | 0.59 | 0.59 |
| Jan 7 | 38.8 | 23.3 | 0.59 | 0.59 | 0.71 | 0.71 |
| Jan 8 | 38.8 | 23.3 | 0.67 | 0.67 | 0.79 | 0.79 |
| Jan 9 | 38.8 | 23.2 | 0.75 | 0.75 | 0.98 | 0.98 |
| Jan 10 | 38.8 | 23.2 | 0.83 | 0.83 | 1.10 | 1.10 |
| Jan 11 | 38.8 | 23.2 | 0.91 | 0.91 | 1.18 | 1.18 |
| Jan 12 | 38.8 | 23.1 | 0.94 | 0.94 | 1.30 | 1.30 |
| Jan 13 | 38.8 | 23.1 | 1.02 | 1.02 | 1.42 | 1.42 |
| Jan 14 | 38.8 | 23.1 | 1.10 | 1.10 | 1.50 | 1.50 |
| Jan 15 | 38.9 | 23.1 | 1.14 | 1.14 | 1.61 | 1.61 |
| Jan 16 | 38.9 | 23.1 | 1.22 | 1.22 | 1.81 | 1.81 |
| Jan 17 | 38.9 | 23.1 | 1.30 | 1.30 | 1.89 | 1.89 |
| Jan 18 | 39.0 | 23.1 | 1.38 | 1.38 | 2.09 | 2.09 |
| Jan 19 | 39.1 | 23.1 | 1.46 | 1.46 | 2.20 | 2.20 |
| Jan 20 | 39.1 | 23.1 | 1.54 | 1.54 | 2.40 | 2.40 |
| Jan 21 | 39.2 | 23.1 | 1.61 | 1.61 | 2.60 | 2.60 |
| Jan 22 | 39.3 | 23.1 | 1.69 | 1.69 | 2.80 | 2.80 |
| Jan 23 | 39.4 | 23.2 | 1.77 | 1.77 | 2.91 | 2.91 |
| Jan 24 | 39.5 | 23.2 | 1.85 | 1.85 | 3.11 | 3.11 |
| Jan 25 | 39.6 | 23.3 | 1.97 | 1.97 | 3.19 | 3.19 |
| Jan 26 | 39.7 | 23.3 | 2.05 | 2.05 | 3.39 | 3.39 |
| Jan 27 | 39.9 | 23.4 | 2.13 | 2.13 | 3.50 | 3.50 |
| Jan 28 | 40.0 | 23.5 | 2.20 | 2.20 | 3.70 | 3.70 |
| Jan 29 | 40.2 | 23.5 | 2.28 | 2.28 | 3.90 | 3.90 |
| Jan 30 | 40.3 | 23.6 | 2.36 | 2.36 | 4.02 | 4.02 |
| Jan 31 | 40.5 | 23.7 | 2.44 | 2.44 | 4.21 | 4.21 |
Precipitation and snow add up through the month (/mo) and the year (/yr)
Weather history Waterloo - August 2026
| Day | HighºF | LowºF | Precip.inch |
|---|---|---|---|
| Aug 1 | – | – | 0.77 |
| Aug 2 | – | – | 0.08 |
| Aug 3 | – | – | – |
| Aug 4 | – | – | – |
| Aug 5 | – | – | – |
| Aug 6 | – | – | 0.76 |
| Aug 7 | – | – | 0.40 |
| Aug 8 | – | – | – |
| Aug 9 | – | – | – |
| Aug 10 | – | – | – |
| Aug 11 | – | – | – |
| Aug 12 | – | – | – |
| Aug 13 | – | – | – |
| Aug 14 | – | – | – |
| Aug 15 | – | – | 0.06 |
| Aug 16 | – | – | – |
| Aug 17 | – | – | 0.77 |
| Aug 18 | – | – | – |
| Aug 19 | – | – | 0.43 |
| Aug 20 | – | – | – |
| Aug 21 | – | – | – |
| Aug 22 | – | – | – |
| Aug 23 | – | – | – |
| Aug 24 | – | – | – |
| Aug 25 | – | – | – |
| Aug 26 | – | – | – |
| Aug 27 | – | – | – |
| Aug 28 | – | – | – |
| Aug 29 | – | – | – |
| Aug 30 | – | – | – |
| Aug 31 | – | – | – |
The data for August 2026 is incomplete: some days or values are missing.
- –No data
- –Not yet observed or received
- TTrace, too small to measure
Observed extremes
Geo Waterloo - Illinois
Location
- Country
- United States
- State
- Illinois
- County
- Monroe
- City
- Waterloo
- Zip Code
- 62298
- Elevation
- 659 ft
- Longitude
- -90.15
- Latitude
- 38.33
- ICAO
- –
- IATA
- –