July is one of the warmer months of the year in Dorchester, with average highs near 27.3°C and lows around 16.9°C (mean 22.1°C). It is about average for rainfall, averaging 100 mm of rainfall and 75% relative humidity across the period.
July is one of the warmer months of the year in Dorchester. Across 45 years of records, the warmest July in Dorchester was 2022 — when the month averaged 24.5°C — while the coldest was 2000 at 19.4°C. Typical July days reach 27.3°C with nights near 16.9°C. The long-term trend is warming, about 0.5°C per decade.
July is about average for rainfall in Dorchester, averaging 100 mm of rainfall. The wettest July on record was 2021 with 281 mm, while the driest was 1987 at 41 mm.
Relative humidity in Dorchester during July averages 75%. The most humid July was 2021 at 85%, and the least humid was 2022 at 62%.
July receives about 5.9 kWh/m²/day of solar energy in Dorchester. The sunniest Julys were 2018 and 2022 at 6.5 kWh/m²/day, and the cloudiest was 2021 at 4.6.
Average wind speed in Dorchester during July is 0.4 m/s. The windiest Julys were 2020, 2021 and 2025, among others at 0.4 m/s, while the calmest were 2022, 2023 and 2024, 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 | 21.2°C | 21.9°C | 21.4°C | 23.0°C | 23.2°C | +2°C |
| Avg High | 26.4°C | 27.4°C | 26.4°C | 28.2°C | 28.3°C | +1.9°C |
| Avg Low | 16.0°C | 16.5°C | 16.4°C | 17.8°C | 18.3°C | +2.3°C |
| Avg Rain | 108 mm | 80 mm | 107 mm | 88 mm | 131 mm | +23 mm |
July temperatures in Dorchester have risen by about 1.7°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 7.2°C (1988) to a record high of 36.8°C (2025).
Rainfall in July is about average for rainfall, averaging 100 mm, with a wettest year of 281 mm.
One of the best times to visit Dorchester
July is one of the best times to visit Dorchester. Expect days averaging 27.3°C and nights around 16.9°C (mean 22.1°C) — warmer than Dorchester's yearly average — with higher rainfall (100 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 | 29.1°C | 23.6°C | 18.2°C | 36.8°C | 12.7°C | 84 mm | 73% | 0.4 m/s | 5.9 |
| 2024 | 28.1°C | 23.4°C | 18.7°C | 32.1°C | 14.9°C | 83 mm | 78% | 0.3 m/s | 5.8 |
| 2023 | 27.3°C | 23.0°C | 18.8°C | 33.2°C | 14.1°C | 234 mm | 84% | 0.3 m/s | 5.4 |
| 2022 🔥 | 30.5°C | 24.5°C | 18.6°C | 36.1°C | 13.2°C | 44 mm | 62% | 0.3 m/s | 6.5 |
| 2021 🌧️ | 24.7°C | 20.5°C | 16.3°C | 30.0°C | 11.5°C | 281 mm | 85% | 0.4 m/s | 4.6 |
| 2020 | 29.8°C | 24.4°C | 19.0°C | 35.6°C | 14.6°C | 62 mm | 72% | 0.4 m/s | 6.1 |
| 2019 | 28.5°C | 23.5°C | 18.4°C | 32.6°C | 13.8°C | 128 mm | 78% | 0.4 m/s | 6.4 |
| 2018 | 28.7°C | 23.2°C | 17.7°C | 33.7°C | 12.3°C | 99 mm | 75% | 0.4 m/s | 6.5 |
| 2017 | 25.7°C | 21.0°C | 16.3°C | 30.6°C | 12.6°C | 89 mm | 79% | 0.4 m/s | 5.7 |
| 2016 | 30.2°C | 24.2°C | 18.1°C | 34.7°C | 14.1°C | 53 mm | 65% | 0.3 m/s | 6.1 |
| 2015 | 27.7°C | 22.4°C | 17.1°C | 33.9°C | 12.3°C | 69 mm | 75% | 0.3 m/s | 5.9 |
| 2014 | 26.9°C | 22.0°C | 17.2°C | 31.0°C | 13.7°C | 142 mm | 76% | 0.4 m/s | 6.1 |
| 2013 | 27.7°C | 23.5°C | 19.4°C | 32.3°C | 15.0°C | 102 mm | 83% | 0.3 m/s | 5.5 |
| 2012 | 29.1°C | 23.6°C | 18.0°C | 35.3°C | 13.9°C | 66 mm | 69% | 0.3 m/s | 6.1 |
| 2011 | 28.3°C | 23.0°C | 17.8°C | 35.6°C | 14.1°C | 65 mm | 75% | 0.4 m/s | 6.3 |
| 2010 | 29.6°C | 24.0°C | 18.4°C | 34.8°C | 12.0°C | 67 mm | 70% | 0.4 m/s | 6.3 |
| 2009 | 24.1°C | 19.7°C | 15.3°C | 27.8°C | 10.7°C | 220 mm | 83% | 0.4 m/s | 5.3 |
| 2008 | 27.8°C | 22.8°C | 17.8°C | 32.3°C | 15.2°C | 173 mm | 77% | 0.3 m/s | 5.8 |
| 2007 | 26.4°C | 21.4°C | 16.4°C | 32.8°C | 10.7°C | 100 mm | 77% | 0.3 m/s | 5.8 |
| 2006 | 27.0°C | 22.5°C | 18.0°C | 31.4°C | 14.3°C | 94 mm | 83% | 0.3 m/s | 5.8 |
| 2005 | 26.5°C | 21.5°C | 16.6°C | 33.0°C | 12.8°C | 84 mm | 80% | 0.4 m/s | 5.9 |
| 2004 | 26.0°C | 21.1°C | 16.2°C | 30.9°C | 13.8°C | 99 mm | 77% | 0.4 m/s | 5.2 |
| 2003 | 26.7°C | 21.9°C | 17.2°C | 29.6°C | 14.5°C | 61 mm | 79% | 0.3 m/s | 6 |
| 2002 | 29.5°C | 23.2°C | 16.9°C | 36.4°C | 11.6°C | 45 mm | 66% | 0.4 m/s | 6.2 |
| 2001 | 26.2°C | 20.3°C | 14.4°C | 33.8°C | 10.1°C | 61 mm | 69% | 0.4 m/s | 6.4 |
| 2000 ❄️ | 24.1°C | 19.4°C | 14.7°C | 27.8°C | 11.4°C | 129 mm | 79% | 0.4 m/s | 5.4 |
| 1999 | 30.5°C | 24.1°C | 17.8°C | 35.8°C | 12.6°C | 75 mm | 64% | 0.3 m/s | 6.1 |
| 1998 | 25.7°C | 20.9°C | 16.2°C | 29.3°C | 13.2°C | 46 mm | 81% | 0.3 m/s | 6 |
| 1997 | 27.6°C | 21.6°C | 15.7°C | 32.3°C | 12.4°C | 63 mm | 68% | 0.4 m/s | 6.2 |
| 1996 | 25.0°C | 20.4°C | 15.8°C | 28.2°C | 12.6°C | 155 mm | 80% | 0.4 m/s | 5.5 |
| 1995 | 29.4°C | 23.5°C | 17.6°C | 35.1°C | 13.1°C | 78 mm | 69% | 0.3 m/s | 5.6 |
| 1994 | 29.1°C | 23.6°C | 18.1°C | 33.7°C | 12.9°C | 70 mm | 73% | 0.3 m/s | 5.9 |
| 1993 | 28.1°C | 22.4°C | 16.7°C | 34.3°C | 13.1°C | 56 mm | 67% | 0.3 m/s | 6 |
| 1992 | 25.0°C | 19.6°C | 14.3°C | 28.8°C | 10.2°C | 94 mm | 75% | 0.4 m/s | 6 |
| 1991 | 27.8°C | 22.1°C | 16.4°C | 35.7°C | 11.3°C | 70 mm | 68% | 0.4 m/s | 5.6 |
| 1990 | 25.5°C | 20.7°C | 16.0°C | 29.9°C | 11.0°C | 94 mm | 80% | 0.4 m/s | 5.7 |
| 1989 | 25.3°C | 20.6°C | 15.8°C | 30.4°C | 12.9°C | 120 mm | 81% | 0.4 m/s | 5.7 |
| 1988 | 28.1°C | 22.6°C | 17.2°C | 34.0°C | 7.2°C | 189 mm | 76% | 0.3 m/s | 5.3 |
| 1987 | 27.1°C | 21.6°C | 16.1°C | 33.5°C | 12.1°C | 41 mm | 75% | 0.3 m/s | 5.6 |
| 1986 | 24.6°C | 19.8°C | 15.0°C | 30.8°C | 9.4°C | 133 mm | 80% | 0.4 m/s | 5.5 |
| 1985 | 27.6°C | 21.6°C | 15.7°C | 30.6°C | 11.1°C | 110 mm | 68% | 0.4 m/s | 6.4 |
| 1984 | 24.8°C | 20.5°C | 16.1°C | 28.9°C | 11.7°C | 122 mm | 83% | 0.4 m/s | 5.7 |
| 1983 | 26.7°C | 21.4°C | 16.1°C | 31.2°C | 10.6°C | 48 mm | 76% | 0.4 m/s | — |
| 1982 | 25.7°C | 20.7°C | 15.6°C | 30.0°C | 10.1°C | 95 mm | 80% | 0.4 m/s | — |
| 1981 | 28.1°C | 22.4°C | 16.7°C | 33.1°C | 12.4°C | 119 mm | 71% | 0.4 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 27.3°C with lows near 16.9°C (mean 22.1°C), based on 45 years of NASA POWER data.
July averages 100 mm of rainfall in Dorchester, about average for rainfall. The wettest on record was 281 mm in 2021.
The hottest July reached 36.8°C in 2025. The coldest dipped to 7.2°C in 1988.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 1.7°C. Daytime highs moved from 26.6°C to 27.9°C and overnight lows from 16°C to 18.1°C over the same span.
July is one of the warmer months of the year in Dorchester and about average for rainfall, so plan for around 27.3°C daytime highs and 16.9°C at night.
Not quite — July is the 12th coolest month in Dorchester, averaging 22.1°C.
For July in Dorchester, pack light layers you can adjust through the day, with typical highs of 27.3°C and lows of 16.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in July averages 75% — quite humid.
Average wind speed in July is 0.4 m/s. The windiest July on record averaged 0.4 m/s (1981).
The wettest July on record was 2021 with 281 mm. On average, July sees 100 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 Dorchester behaves each July, 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 July specifically, along with year-by-year records and how the month has changed over the decades.
