August is one of the warmer months of the year in St. John's, with average highs near 17.3°C and lows around 13.7°C (mean 15.5°C). It is one of the drier months, averaging 88 mm of rainfall and 88% relative humidity across the period.
August is one of the warmer months of the year in St. John's. Across 45 years of records, the warmest August in St. John's was 2022 — when the month averaged 18°C — while the coldest was 1991 at 13.2°C. Typical August days reach 17.3°C with nights near 13.7°C. The long-term trend is warming, about 0.5°C per decade.
August is one of the drier months in St. John's, averaging 88 mm of rainfall. The wettest August on record was 2008 with 125 mm, while the driest was 2015 at 46 mm.
Relative humidity in St. John's during August averages 88%. The most humid August was 2011 at 92%, and the least humid was 2025 at 85%.
August receives about 4.4 kWh/m²/day of solar energy in St. John's. The sunniest Augusts were 1984 and 2020 at 5 kWh/m²/day, and the cloudiest were 2008 and 2014 at 3.7.
Average wind speed in St. John's during August is 3.9 m/s. The windiest August was 2013 at 4.9 m/s, while the calmest was 1996 at 3.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 14.7°C | 14.9°C | 15.7°C | 15.8°C | 16.6°C | +1.9°C |
| Avg High | 16.6°C | 16.8°C | 17.5°C | 17.5°C | 18.4°C | +1.8°C |
| Avg Low | 12.8°C | 13.1°C | 14.0°C | 14.2°C | 14.7°C | +1.9°C |
| Avg Rain | 92 mm | 82 mm | 98 mm | 84 mm | 81 mm | -11 mm |
August temperatures in St. John's have risen by about 2.2°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 7.8°C (2002) to a record high of 24.2°C (2018).
Rainfall in August is one of the drier months, averaging 88 mm, with a wettest year of 125 mm.
One of the best times to visit St. John's
August is one of the best times to visit St. John's. Expect days averaging 17.3°C and nights around 13.7°C (mean 15.5°C) — warmer than St. John's's yearly average — with higher rainfall (88 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 | 17.4°C | 15.4°C | 13.3°C | 22.2°C | 10.5°C | 79 mm | 85% | 3.6 m/s | 4.9 |
| 2024 | 19.5°C | 17.5°C | 15.5°C | 23.1°C | 11.3°C | 73 mm | 87% | 3.9 m/s | 4.4 |
| 2023 | 17.1°C | 15.8°C | 14.4°C | 20.3°C | 12.3°C | 118 mm | 91% | 3.7 m/s | 4.1 |
| 2022 🔥 | 19.7°C | 18.0°C | 16.2°C | 23.3°C | 13.6°C | 72 mm | 88% | 3.6 m/s | 4.4 |
| 2021 | 18.2°C | 16.2°C | 14.2°C | 22.0°C | 11.9°C | 66 mm | 86% | 4.4 m/s | 4.7 |
| 2020 | 18.6°C | 16.6°C | 14.6°C | 22.2°C | 12.1°C | 75 mm | 86% | 4 m/s | 5 |
| 2019 | 17.9°C | 16.2°C | 14.5°C | 20.7°C | 11.8°C | 63 mm | 88% | 3.6 m/s | 4.5 |
| 2018 | 18.4°C | 16.5°C | 14.5°C | 24.2°C | 12.3°C | 58 mm | 89% | 3.6 m/s | 4.5 |
| 2017 | 17.1°C | 15.5°C | 13.9°C | 20.5°C | 11.8°C | 89 mm | 88% | 3.9 m/s | 4.6 |
| 2016 | 17.4°C | 15.7°C | 14.0°C | 20.2°C | 10.0°C | 98 mm | 86% | 4.3 m/s | 4.5 |
| 2015 | 17.4°C | 15.7°C | 14.0°C | 20.0°C | 10.6°C | 46 mm | 90% | 3.9 m/s | 4.5 |
| 2014 | 17.5°C | 16.3°C | 15.1°C | 21.8°C | 9.6°C | 104 mm | 90% | 4.3 m/s | 3.7 |
| 2013 | 17.8°C | 16.0°C | 14.3°C | 21.5°C | 10.2°C | 119 mm | 88% | 4.9 m/s | 4.4 |
| 2012 | 19.0°C | 17.3°C | 15.6°C | 22.1°C | 13.3°C | 73 mm | 88% | 3.9 m/s | 4.3 |
| 2011 | 15.2°C | 13.7°C | 12.2°C | 19.4°C | 9.2°C | 96 mm | 92% | 3.8 m/s | 4.1 |
| 2010 | 17.0°C | 15.5°C | 14.0°C | 20.1°C | 12.1°C | 92 mm | 89% | 3.5 m/s | 4.2 |
| 2009 | 17.9°C | 15.9°C | 13.9°C | 20.9°C | 9.6°C | 124 mm | 87% | 4 m/s | 4.1 |
| 2008 🌧️ | 16.6°C | 15.2°C | 13.8°C | 19.7°C | 12.3°C | 125 mm | 91% | 4.4 m/s | 3.7 |
| 2007 | 16.8°C | 15.1°C | 13.4°C | 20.1°C | 10.9°C | 107 mm | 88% | 3.7 m/s | 4.7 |
| 2006 | 17.2°C | 15.7°C | 14.2°C | 20.4°C | 11.5°C | 116 mm | 87% | 4.3 m/s | 4.4 |
| 2005 | 17.7°C | 16.0°C | 14.3°C | 20.1°C | 12.8°C | 124 mm | 88% | 3.7 m/s | 4.4 |
| 2004 | 18.6°C | 16.8°C | 15.0°C | 21.8°C | 11.6°C | 76 mm | 88% | 3.8 m/s | 4.2 |
| 2003 | 17.3°C | 15.5°C | 13.7°C | 20.1°C | 10.4°C | 77 mm | 86% | 3.9 m/s | 4.6 |
| 2002 | 17.2°C | 15.3°C | 13.4°C | 21.4°C | 7.8°C | 61 mm | 88% | 3.9 m/s | 4.5 |
| 2001 | 17.7°C | 15.8°C | 14.0°C | 20.8°C | 10.3°C | 70 mm | 89% | 3.6 m/s | 4.3 |
| 2000 | 17.6°C | 15.9°C | 14.2°C | 20.4°C | 11.7°C | 103 mm | 89% | 3.7 m/s | 4.2 |
| 1999 | 18.4°C | 16.5°C | 14.6°C | 22.3°C | 12.0°C | 66 mm | 87% | 4.1 m/s | 4.4 |
| 1998 | 18.0°C | 16.2°C | 14.4°C | 21.1°C | 11.4°C | 90 mm | 87% | 3.7 m/s | 4.7 |
| 1997 | 16.5°C | 14.7°C | 12.8°C | 20.8°C | 10.0°C | 98 mm | 89% | 3.5 m/s | 4 |
| 1996 | 17.5°C | 15.7°C | 13.9°C | 22.0°C | 11.3°C | 69 mm | 89% | 3.2 m/s | 4.7 |
| 1995 | 15.5°C | 13.5°C | 11.6°C | 20.8°C | 9.8°C | 96 mm | 87% | 3.9 m/s | 4.6 |
| 1994 | 18.7°C | 16.8°C | 14.9°C | 21.4°C | 12.6°C | 73 mm | 87% | 3.9 m/s | 4.8 |
| 1993 | 15.2°C | 13.6°C | 11.9°C | 19.3°C | 9.1°C | 98 mm | 89% | 3.9 m/s | 4.2 |
| 1992 | 15.3°C | 13.4°C | 11.5°C | 18.5°C | 9.2°C | 77 mm | 88% | 4.2 m/s | 4.3 |
| 1991 ❄️ | 15.2°C | 13.2°C | 11.2°C | 18.6°C | 8.3°C | 76 mm | 88% | 4 m/s | 3.9 |
| 1990 | 17.6°C | 15.7°C | 13.8°C | 21.0°C | 10.2°C | 76 mm | 88% | 4.1 m/s | 4.5 |
| 1989 | 17.9°C | 15.8°C | 13.6°C | 21.4°C | 9.4°C | 70 mm | 86% | 4.2 m/s | 4.4 |
| 1988 | 17.3°C | 15.3°C | 13.3°C | 20.4°C | 10.8°C | 65 mm | 87% | 3.6 m/s | 4.5 |
| 1987 | 16.4°C | 14.6°C | 12.8°C | 22.6°C | 10.2°C | 79 mm | 86% | 3.7 m/s | 4.3 |
| 1986 | 16.5°C | 14.7°C | 12.9°C | 19.9°C | 10.7°C | 69 mm | 88% | 3.4 m/s | 4.8 |
| 1985 | 15.0°C | 13.3°C | 11.5°C | 19.2°C | 9.5°C | 123 mm | 89% | 3.5 m/s | 4.3 |
| 1984 | 17.8°C | 15.7°C | 13.6°C | 21.3°C | 10.9°C | 117 mm | 89% | 3.5 m/s | 5 |
| 1983 | 15.4°C | 13.6°C | 11.8°C | 19.2°C | 8.7°C | 105 mm | 88% | 4.3 m/s | — |
| 1982 | 16.3°C | 14.3°C | 12.4°C | 19.9°C | 9.7°C | 103 mm | 86% | 3.5 m/s | — |
| 1981 | 17.1°C | 15.1°C | 13.2°C | 20.0°C | 10.3°C | 97 mm | 88% | 4.3 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 17.3°C with lows near 13.7°C (mean 15.5°C), based on 45 years of NASA POWER data.
August averages 88 mm of rainfall in St. John's, one of the drier months. The wettest on record was 125 mm in 2008.
The hottest August reached 24.2°C in 2018. The coldest dipped to 7.8°C in 2002.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 2.2°C. Daytime highs moved from 16.3°C to 18.4°C and overnight lows from 12.5°C to 14.7°C over the same span.
August is one of the warmer months of the year in St. John's and one of the drier months, so plan for around 17.3°C daytime highs and 13.7°C at night.
Not quite — August is the 12th coolest month in St. John's, averaging 15.5°C.
For August in St. John's, pack light layers you can adjust through the day, with typical highs of 17.3°C and lows of 13.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in August averages 88% — quite humid.
Average wind speed in August is 3.9 m/s. The windiest August on record averaged 4.9 m/s (2013).
The wettest August on record was 2008 with 125 mm. On average, August sees 88 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 St. John's behaves each August, 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 August specifically, along with year-by-year records and how the month has changed over the decades.
