June is one of the warmer months of the year in Waltham, with average highs near 23.5°C and lows around 13.3°C (mean 18.4°C). It is about average for rainfall, averaging 101 mm of rainfall and 79% relative humidity across the period.
June is one of the warmer months of the year in Waltham. Across 45 years of records, the warmest June in Waltham was 1999 — when the month averaged 20.8°C — while the coldest was 1982 at 15.9°C. Typical June days reach 23.5°C with nights near 13.3°C. The long-term trend is warming, about 0.4°C per decade.
June is about average for rainfall in Waltham, averaging 101 mm of rainfall. The wettest June on record was 1998 with 277 mm, while the driest was 1999 at 29 mm.
Relative humidity in Waltham during June averages 79%. The most humid June was 2006 at 86%, and the least humid was 1999 at 66%.
June receives about 5.7 kWh/m²/day of solar energy in Waltham. The sunniest June was 2016 at 6.7 kWh/m²/day, and the cloudiest was 2009 at 4.4.
Average wind speed in Waltham during June is 0.4 m/s. The windiest June was 2012 at 0.5 m/s, while the calmest were 2005, 2008 and 2020, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 17.6°C | 18.4°C | 18.4°C | 18.5°C | 19.5°C | +1.9°C |
| Avg High | 22.7°C | 23.7°C | 23.4°C | 23.5°C | 24.6°C | +1.9°C |
| Avg Low | 12.5°C | 13.2°C | 13.3°C | 13.5°C | 14.3°C | +1.8°C |
| Avg Rain | 111 mm | 78 mm | 115 mm | 116 mm | 77 mm | -34 mm |
June temperatures in Waltham have risen by about 1.7°C between 1981–1985 and 2021–2025.
June has ranged from a record low of 4.6°C (1986) to a record high of 34.5°C (2021).
Rainfall in June is about average for rainfall, averaging 101 mm, with a wettest year of 277 mm.
One of the best times to visit Waltham
June is one of the best times to visit Waltham. Expect days averaging 23.5°C and nights around 13.3°C (mean 18.4°C) — warmer than Waltham's yearly average — with higher rainfall (101 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 | 24.7°C | 19.6°C | 14.6°C | 33.9°C | 7.6°C | 47 mm | 79% | 0.4 m/s | 5.6 |
| 2024 | 25.2°C | 20.0°C | 14.7°C | 31.9°C | 10.0°C | 82 mm | 79% | 0.4 m/s | 6.2 |
| 2023 | 22.4°C | 17.9°C | 13.4°C | 32.9°C | 6.8°C | 125 mm | 83% | 0.4 m/s | 5.1 |
| 2022 | 24.3°C | 18.9°C | 13.5°C | 32.8°C | 9.3°C | 65 mm | 72% | 0.4 m/s | 6.2 |
| 2021 | 26.0°C | 20.7°C | 15.4°C | 34.5°C | 10.3°C | 61 mm | 76% | 0.4 m/s | 6.4 |
| 2020 | 25.1°C | 19.7°C | 14.2°C | 31.8°C | 4.7°C | 80 mm | 76% | 0.3 m/s | 6.2 |
| 2019 | 23.3°C | 18.4°C | 13.5°C | 30.0°C | 7.2°C | 122 mm | 79% | 0.4 m/s | 5.9 |
| 2018 | 23.2°C | 18.1°C | 12.9°C | 32.2°C | 7.6°C | 99 mm | 78% | 0.4 m/s | 5.9 |
| 2017 | 23.4°C | 18.6°C | 13.7°C | 29.9°C | 8.2°C | 113 mm | 80% | 0.4 m/s | 5.9 |
| 2016 | 24.8°C | 19.2°C | 13.6°C | 31.0°C | 9.9°C | 46 mm | 69% | 0.4 m/s | 6.7 |
| 2015 | 22.3°C | 17.5°C | 12.6°C | 27.7°C | 6.1°C | 158 mm | 80% | 0.4 m/s | 5.6 |
| 2014 | 24.1°C | 18.8°C | 13.6°C | 29.3°C | 7.4°C | 66 mm | 78% | 0.4 m/s | 6.3 |
| 2013 | 23.9°C | 19.1°C | 14.3°C | 29.3°C | 9.7°C | 230 mm | 81% | 0.4 m/s | 5.7 |
| 2012 | 22.8°C | 18.0°C | 13.1°C | 32.0°C | 8.9°C | 127 mm | 79% | 0.5 m/s | 5.9 |
| 2011 | 22.7°C | 18.0°C | 13.4°C | 29.4°C | 7.5°C | 122 mm | 81% | 0.4 m/s | 5.6 |
| 2010 | 24.8°C | 19.7°C | 14.6°C | 30.5°C | 9.0°C | 75 mm | 80% | 0.4 m/s | 5.6 |
| 2009 | 21.4°C | 16.9°C | 12.4°C | 26.0°C | 4.9°C | 138 mm | 84% | 0.4 m/s | 4.4 |
| 2008 | 24.6°C | 19.5°C | 14.4°C | 33.2°C | 10.8°C | 92 mm | 81% | 0.3 m/s | 5.5 |
| 2007 | 22.9°C | 18.0°C | 13.0°C | 30.8°C | 7.4°C | 74 mm | 80% | 0.4 m/s | 5.9 |
| 2006 | 22.5°C | 18.5°C | 14.5°C | 31.6°C | 9.2°C | 246 mm | 86% | 0.4 m/s | 4.6 |
| 2005 | 24.9°C | 19.4°C | 13.9°C | 33.8°C | 7.2°C | 53 mm | 82% | 0.3 m/s | 5.6 |
| 2004 | 23.0°C | 17.6°C | 12.2°C | 29.2°C | 8.0°C | 58 mm | 77% | 0.4 m/s | 6.1 |
| 2003 | 22.4°C | 17.6°C | 12.9°C | 33.1°C | 7.4°C | 120 mm | 82% | 0.4 m/s | 5.1 |
| 2002 | 23.3°C | 17.8°C | 12.2°C | 31.5°C | 6.3°C | 99 mm | 77% | 0.4 m/s | 5.9 |
| 2001 | 25.7°C | 20.2°C | 14.6°C | 31.5°C | 5.8°C | 143 mm | 78% | 0.3 m/s | 6.1 |
| 2000 | 23.3°C | 18.1°C | 12.9°C | 28.8°C | 5.9°C | 132 mm | 81% | 0.4 m/s | 5.1 |
| 1999 🔥 | 26.9°C | 20.8°C | 14.7°C | 34.3°C | 8.9°C | 29 mm | 66% | 0.4 m/s | 6.4 |
| 1998 🌧️ | 22.0°C | 17.4°C | 12.8°C | 28.5°C | 6.1°C | 277 mm | 83% | 0.4 m/s | 4.8 |
| 1997 | 23.4°C | 18.0°C | 12.6°C | 31.6°C | 6.1°C | 29 mm | 76% | 0.4 m/s | 6.3 |
| 1996 | 23.2°C | 18.3°C | 13.5°C | 27.1°C | 7.0°C | 60 mm | 81% | 0.4 m/s | 5.4 |
| 1995 | 24.0°C | 18.4°C | 12.8°C | 30.7°C | 8.3°C | 53 mm | 75% | 0.4 m/s | 5.9 |
| 1994 | 24.7°C | 19.5°C | 14.4°C | 31.9°C | 7.0°C | 46 mm | 80% | 0.4 m/s | 5.7 |
| 1993 | 23.3°C | 18.1°C | 12.8°C | 28.3°C | 6.6°C | 47 mm | 76% | 0.4 m/s | 6.2 |
| 1992 | 22.9°C | 17.5°C | 12.1°C | 27.2°C | 7.7°C | 121 mm | 78% | 0.4 m/s | 6.3 |
| 1991 | 23.6°C | 18.5°C | 13.3°C | 31.5°C | 8.5°C | 69 mm | 75% | 0.4 m/s | 6.1 |
| 1990 | 22.7°C | 17.7°C | 12.8°C | 26.3°C | 7.6°C | 47 mm | 82% | 0.4 m/s | 5.7 |
| 1989 | 22.8°C | 18.2°C | 13.5°C | 28.8°C | 9.8°C | 121 mm | 83% | 0.4 m/s | 5.3 |
| 1988 | 22.6°C | 17.2°C | 11.8°C | 30.1°C | 6.7°C | 38 mm | 74% | 0.4 m/s | 6.6 |
| 1987 | 22.8°C | 17.9°C | 13.1°C | 27.2°C | 6.8°C | 75 mm | 80% | 0.4 m/s | 5.6 |
| 1986 | 21.3°C | 16.1°C | 10.9°C | 25.9°C | 4.6°C | 170 mm | 79% | 0.4 m/s | 5.8 |
| 1985 | 21.7°C | 16.6°C | 11.5°C | 27.1°C | 7.8°C | 99 mm | 75% | 0.4 m/s | 4.9 |
| 1984 | 23.5°C | 18.6°C | 13.7°C | 30.3°C | 7.2°C | 92 mm | 83% | 0.4 m/s | 5.4 |
| 1983 | 24.0°C | 18.5°C | 13.1°C | 31.4°C | 6.3°C | 51 mm | 80% | 0.3 m/s | — |
| 1982 ❄️ | 20.5°C | 15.9°C | 11.3°C | 25.8°C | 6.6°C | 274 mm | 83% | 0.4 m/s | — |
| 1981 | 24.7°C | 19.0°C | 13.3°C | 31.5°C | 8.2°C | 74 mm | 73% | 0.4 m/s | — |
Actual recorded June data for each year, 1981–2025 — sourced from NASA POWER.
The average high in June is around 23.5°C with lows near 13.3°C (mean 18.4°C), based on 45 years of NASA POWER data.
June averages 101 mm of rainfall in Waltham, about average for rainfall. The wettest on record was 277 mm in 1998.
The hottest June reached 34.5°C in 2021. The coldest dipped to 4.6°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average June temperatures have risen by about 1.7°C. Daytime highs moved from 22.9°C to 24.5°C and overnight lows from 12.6°C to 14.3°C over the same span.
June is one of the warmer months of the year in Waltham and about average for rainfall, so plan for around 23.5°C daytime highs and 13.3°C at night.
Not quite — June is the 10th coolest month in Waltham, averaging 18.4°C.
For June in Waltham, pack light layers you can adjust through the day, with typical highs of 23.5°C and lows of 13.3°C. Bring an umbrella or light rain jacket too.
Relative humidity in June averages 79% — quite humid.
Average wind speed in June is 0.4 m/s. The windiest June on record averaged 0.5 m/s (2012).
The wettest June on record was 1998 with 277 mm. On average, June sees 101 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 Waltham 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.
