June is one of the warmer months of the year in Waterloo, with average highs near 23.9°C and lows around 11.7°C (mean 17.8°C). It is a relatively wet time of year, averaging 72 mm of rainfall and 72% relative humidity across the period.
June is one of the warmer months of the year in Waterloo. Across 45 years of records, the warmest June in Waterloo was 2005 — when the month averaged 21.5°C — while the coldest was 1985 at 14.3°C. Typical June days reach 23.9°C with nights near 11.7°C. The long-term trend is warming, about 0.3°C per decade.
June is a relatively wet time of year in Waterloo, averaging 72 mm of rainfall. The wettest June on record was 2000 with 181 mm, while the driest was 1988 at 20 mm.
Relative humidity in Waterloo during June averages 72%. The most humid June was 2000 at 83%, and the least humid was 1988 at 53%.
June receives about 6.2 kWh/m²/day of solar energy in Waterloo. The sunniest June was 2020 at 7.2 kWh/m²/day, and the cloudiest was 1996 at 5.
Average wind speed in Waterloo during June is 2.9 m/s. The windiest June was 1988 at 3.6 m/s, while the calmest were 1983, 2001 and 2009 at 2.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 17.1°C | 18.1°C | 17.7°C | 17.5°C | 19.1°C | +2°C |
| Avg High | 23.3°C | 24.4°C | 23.6°C | 23.4°C | 25.4°C | +2.1°C |
| Avg Low | 10.8°C | 11.8°C | 11.8°C | 11.6°C | 12.8°C | +2°C |
| Avg Rain | 63 mm | 71 mm | 69 mm | 89 mm | 63 mm | -1 mm |
June temperatures in Waterloo have risen by about 2.9°C between 1981–1985 and 2021–2025.
June has ranged from a record low of 1°C (1983) to a record high of 36.7°C (1988).
Rainfall in June is a relatively wet time of year, averaging 72 mm, with a wettest year of 181 mm.
One of the best times to visit Waterloo
June is one of the best times to visit Waterloo. Expect days averaging 23.9°C and nights around 11.7°C (mean 17.8°C) — warmer than Waterloo's yearly average — with moderate rainfall (72 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 25.6°C | 19.5°C | 13.3°C | 34.4°C | 2.7°C | 62 mm | 71% | 3.1 m/s | 6 |
| 2024 | 25.0°C | 19.3°C | 13.6°C | 31.8°C | 7.9°C | 59 mm | 72% | 2.9 m/s | 5.7 |
| 2023 | 24.3°C | 18.2°C | 12.2°C | 30.3°C | 7.8°C | 67 mm | 67% | 2.7 m/s | 6 |
| 2022 | 24.5°C | 17.5°C | 10.6°C | 32.4°C | 4.0°C | 49 mm | 67% | 2.9 m/s | 6.7 |
| 2021 | 27.1°C | 20.8°C | 14.6°C | 32.4°C | 7.4°C | 86 mm | 66% | 3.2 m/s | 6.3 |
| 2020 | 26.0°C | 19.3°C | 12.6°C | 31.6°C | 5.1°C | 54 mm | 64% | 2.8 m/s | 7.2 |
| 2019 | 22.1°C | 16.3°C | 10.5°C | 27.9°C | 3.0°C | 56 mm | 76% | 2.8 m/s | 6.2 |
| 2018 | 24.5°C | 18.4°C | 12.2°C | 31.7°C | 6.8°C | 68 mm | 72% | 2.9 m/s | 6 |
| 2017 | 22.5°C | 17.3°C | 12.1°C | 28.2°C | 4.6°C | 130 mm | 80% | 3 m/s | 6.1 |
| 2016 | 24.2°C | 17.6°C | 11.1°C | 30.7°C | 4.4°C | 39 mm | 68% | 3 m/s | 7 |
| 2015 | 22.4°C | 16.4°C | 10.4°C | 27.2°C | 3.7°C | 142 mm | 79% | 2.8 m/s | 5.8 |
| 2014 | 23.6°C | 17.6°C | 11.7°C | 28.4°C | 6.3°C | 76 mm | 77% | 2.6 m/s | 6.3 |
| 2013 | 22.0°C | 16.9°C | 11.8°C | 28.4°C | 3.7°C | 101 mm | 80% | 2.6 m/s | 5.8 |
| 2012 | 25.3°C | 19.0°C | 12.7°C | 33.3°C | 6.7°C | 93 mm | 70% | 3.2 m/s | 6.4 |
| 2011 | 22.6°C | 16.9°C | 11.3°C | 27.6°C | 4.3°C | 64 mm | 79% | 2.9 m/s | 6 |
| 2010 | 24.4°C | 18.5°C | 12.6°C | 30.5°C | 5.0°C | 122 mm | 73% | 3 m/s | 5.8 |
| 2009 | 22.1°C | 16.2°C | 10.4°C | 30.3°C | 2.6°C | 66 mm | 76% | 2.4 m/s | 5.9 |
| 2008 | 23.5°C | 18.3°C | 13.0°C | 30.2°C | 6.7°C | 82 mm | 79% | 2.9 m/s | 5.6 |
| 2007 | 26.7°C | 19.6°C | 12.5°C | 34.5°C | 3.1°C | 25 mm | 60% | 2.8 m/s | 7.1 |
| 2006 | 24.8°C | 18.6°C | 12.4°C | 33.4°C | 4.5°C | 33 mm | 65% | 2.9 m/s | 6.2 |
| 2005 🔥 | 27.8°C | 21.5°C | 15.1°C | 35.2°C | 9.3°C | 28 mm | 70% | 2.5 m/s | 6.3 |
| 2004 | 21.3°C | 15.6°C | 9.9°C | 27.6°C | 3.5°C | 64 mm | 78% | 2.8 m/s | 6.2 |
| 2003 | 22.1°C | 16.0°C | 9.8°C | 31.4°C | 1.9°C | 69 mm | 76% | 3 m/s | 6.2 |
| 2002 | 22.7°C | 17.3°C | 11.9°C | 29.7°C | 3.6°C | 56 mm | 80% | 2.5 m/s | 5.8 |
| 2001 | 23.0°C | 17.5°C | 12.0°C | 29.0°C | 5.0°C | 90 mm | 78% | 2.4 m/s | 6 |
| 2000 🌧️ | 21.8°C | 16.6°C | 11.4°C | 27.5°C | 6.5°C | 181 mm | 83% | 3.2 m/s | 5.2 |
| 1999 | 25.7°C | 19.3°C | 12.8°C | 32.2°C | 5.5°C | 77 mm | 66% | 2.6 m/s | 6.1 |
| 1998 | 24.6°C | 18.3°C | 12.0°C | 32.8°C | 2.2°C | 55 mm | 67% | 3 m/s | 5.9 |
| 1997 | 23.8°C | 17.8°C | 11.8°C | 29.3°C | 7.3°C | 67 mm | 75% | 2.6 m/s | 6.6 |
| 1996 | 23.7°C | 18.1°C | 12.5°C | 29.8°C | 7.0°C | 87 mm | 77% | 2.7 m/s | 5 |
| 1995 | 26.4°C | 19.9°C | 13.4°C | 35.3°C | 6.1°C | 52 mm | 66% | 2.5 m/s | 6.3 |
| 1994 | 25.2°C | 18.5°C | 11.8°C | 34.2°C | 2.7°C | 85 mm | 68% | 2.9 m/s | 6 |
| 1993 | 22.4°C | 16.2°C | 10.0°C | 27.3°C | 2.8°C | 110 mm | 75% | 3 m/s | 6 |
| 1992 | 22.9°C | 16.2°C | 9.6°C | 29.5°C | 1.8°C | 55 mm | 63% | 2.7 m/s | 6.4 |
| 1991 | 25.8°C | 19.3°C | 12.8°C | 30.8°C | 4.5°C | 60 mm | 66% | 2.6 m/s | 6.7 |
| 1990 | 23.3°C | 17.1°C | 10.8°C | 30.6°C | 2.7°C | 64 mm | 71% | 3.5 m/s | 5.7 |
| 1989 | 24.8°C | 18.7°C | 12.6°C | 32.1°C | 6.9°C | 56 mm | 69% | 2.7 m/s | 5.6 |
| 1988 | 26.0°C | 18.1°C | 10.2°C | 36.7°C | 3.4°C | 20 mm | 53% | 3.6 m/s | 7 |
| 1987 | 26.3°C | 19.5°C | 12.8°C | 32.9°C | 4.9°C | 41 mm | 62% | 3 m/s | 6.2 |
| 1986 | 22.6°C | 16.1°C | 9.5°C | 29.4°C | 3.4°C | 77 mm | 71% | 3.3 m/s | 6.3 |
| 1985 ❄️ | 20.3°C | 14.3°C | 8.3°C | 25.3°C | 2.4°C | 48 mm | 73% | 3.1 m/s | 6.7 |
| 1984 | 23.3°C | 17.4°C | 11.5°C | 27.5°C | 5.9°C | 82 mm | 76% | 3.1 m/s | 6.1 |
| 1983 | 23.0°C | 17.0°C | 11.0°C | 28.6°C | 1.0°C | 40 mm | 75% | 2.4 m/s | — |
| 1982 | 19.9°C | 14.6°C | 9.3°C | 25.3°C | 4.4°C | 139 mm | 81% | 2.6 m/s | — |
| 1981 | 23.9°C | 17.8°C | 11.6°C | 30.6°C | 5.4°C | 69 mm | 71% | 3.3 m/s | — |
Actual recorded June data for each year, 1981–2025 — sourced from NASA POWER.
The average high in June is around 23.9°C with lows near 11.7°C (mean 17.8°C), based on 45 years of NASA POWER data.
June averages 72 mm of rainfall in Waterloo, a relatively wet time of year. The wettest on record was 181 mm in 2000.
The hottest June reached 36.7°C in 1988. The coldest dipped to 1°C in 1983.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average June temperatures have risen by about 2.9°C. Daytime highs moved from 22.1°C to 25.3°C and overnight lows from 10.3°C to 12.9°C over the same span.
June is one of the warmer months of the year in Waterloo and a relatively wet time of year, so plan for around 23.9°C daytime highs and 11.7°C at night.
Not quite — June is the 10th coolest month in Waterloo, averaging 17.8°C.
For June in Waterloo, pack light layers you can adjust through the day, with typical highs of 23.9°C and lows of 11.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in June averages 72% — moderately humid.
Average wind speed in June is 2.9 m/s. The windiest June on record averaged 3.6 m/s (1988).
The wettest June on record was 2000 with 181 mm. On average, June sees 72 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Waterloo behaves each June, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for June specifically, along with year-by-year records and how the month has changed over the decades.
