August is one of the warmer months of the year in St. Thomas, with average highs near 27.1°C and lows around 15.9°C (mean 21.5°C). It is about average for rainfall, averaging 63 mm of rainfall and 68% relative humidity across the period.
August is one of the warmer months of the year in St. Thomas. Across 45 years of records, the warmest August in St. Thomas was 2021 — when the month averaged 24.8°C — while the coldest was 1992 at 17.8°C. Typical August days reach 27.1°C with nights near 15.9°C. The long-term trend is warming, about 0.5°C per decade.
August is about average for rainfall in St. Thomas, averaging 63 mm of rainfall. The wettest August on record was 1985 with 125 mm, while the driest was 2002 at 16 mm.
Relative humidity in St. Thomas during August averages 68%. The most humid August was 2000 at 78%, and the least humid was 2025 at 58%.
August receives about 5.4 kWh/m²/day of solar energy in St. Thomas. The sunniest Augusts were 2008 and 2019 at 5.9 kWh/m²/day, and the cloudiest was 1997 at 4.6.
Average wind speed in St. Thomas during August is 2.6 m/s. The windiest August was 1987 at 3.1 m/s, while the calmest were 1996, 1998 and 2003 at 2.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 20.7°C | 21.0°C | 21.6°C | 21.9°C | 22.8°C | +2.1°C |
| Avg High | 26.3°C | 26.7°C | 27.3°C | 27.4°C | 28.6°C | +2.3°C |
| Avg Low | 15.1°C | 15.4°C | 16.0°C | 16.6°C | 17.0°C | +1.9°C |
| Avg Rain | 87 mm | 66 mm | 49 mm | 64 mm | 43 mm | -44 mm |
August temperatures in St. Thomas have risen by about 2.3°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 4.7°C (1982) to a record high of 36.8°C (2001).
Rainfall in August is about average for rainfall, averaging 63 mm, with a wettest year of 125 mm.
One of the best times to visit St. Thomas
August is one of the best times to visit St. Thomas. Expect days averaging 27.1°C and nights around 15.9°C (mean 21.5°C) — warmer than St. Thomas's yearly average — with moderate rainfall (63 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 | 28.4°C | 22.2°C | 16.1°C | 33.9°C | 7.9°C | 30 mm | 58% | 2.5 m/s | 5.7 |
| 2024 | 28.6°C | 22.7°C | 16.8°C | 34.1°C | 9.4°C | 48 mm | 64% | 2.6 m/s | 5.2 |
| 2023 | 26.9°C | 21.1°C | 15.3°C | 30.6°C | 8.6°C | 59 mm | 67% | 2.9 m/s | 5.1 |
| 2022 | 28.7°C | 22.9°C | 17.1°C | 33.5°C | 12.0°C | 40 mm | 64% | 2.6 m/s | 5.6 |
| 2021 🔥 | 30.4°C | 24.8°C | 19.2°C | 34.4°C | 12.8°C | 35 mm | 64% | 2.4 m/s | 5.5 |
| 2020 | 28.5°C | 22.9°C | 17.3°C | 32.6°C | 12.2°C | 48 mm | 67% | 2.8 m/s | 5.6 |
| 2019 | 27.5°C | 21.9°C | 16.3°C | 31.2°C | 11.1°C | 67 mm | 68% | 2.6 m/s | 5.9 |
| 2018 | 27.9°C | 23.1°C | 18.4°C | 32.5°C | 13.3°C | 90 mm | 75% | 2.6 m/s | 5.1 |
| 2017 | 25.5°C | 20.2°C | 15.0°C | 30.8°C | 8.6°C | 47 mm | 71% | 2.7 m/s | 5.3 |
| 2016 | 29.8°C | 24.2°C | 18.6°C | 34.4°C | 14.0°C | 58 mm | 68% | 2.6 m/s | 5.8 |
| 2015 | 26.0°C | 20.7°C | 15.5°C | 31.6°C | 11.3°C | 62 mm | 71% | 2.6 m/s | 5.7 |
| 2014 | 25.9°C | 20.5°C | 15.1°C | 30.1°C | 10.8°C | 65 mm | 73% | 2.6 m/s | 5.5 |
| 2013 | 26.1°C | 20.7°C | 15.3°C | 30.9°C | 10.5°C | 78 mm | 71% | 2.5 m/s | 5.6 |
| 2012 | 26.7°C | 21.3°C | 16.0°C | 32.9°C | 11.0°C | 89 mm | 68% | 2.4 m/s | 5.7 |
| 2011 | 28.6°C | 22.8°C | 17.1°C | 33.9°C | 13.1°C | 59 mm | 64% | 2.6 m/s | 5.7 |
| 2010 | 29.8°C | 24.0°C | 18.3°C | 34.6°C | 12.7°C | 19 mm | 63% | 2.8 m/s | 5.4 |
| 2009 | 26.8°C | 21.4°C | 16.1°C | 31.8°C | 8.9°C | 54 mm | 68% | 2.9 m/s | 5.3 |
| 2008 | 26.6°C | 20.8°C | 15.0°C | 30.8°C | 10.5°C | 43 mm | 66% | 2.7 m/s | 5.9 |
| 2007 | 28.6°C | 22.8°C | 17.0°C | 35.5°C | 10.1°C | 37 mm | 64% | 2.7 m/s | 5 |
| 2006 | 27.8°C | 22.0°C | 16.2°C | 34.5°C | 11.0°C | 34 mm | 65% | 2.7 m/s | 5.4 |
| 2005 | 28.7°C | 23.0°C | 17.3°C | 33.4°C | 11.4°C | 50 mm | 66% | 2.7 m/s | 5.3 |
| 2004 | 24.8°C | 19.6°C | 14.5°C | 28.6°C | 9.5°C | 58 mm | 72% | 2.8 m/s | 5.3 |
| 2003 | 27.5°C | 22.1°C | 16.6°C | 32.6°C | 11.3°C | 47 mm | 70% | 2.2 m/s | 5.6 |
| 2002 | 28.8°C | 22.5°C | 16.2°C | 33.6°C | 11.6°C | 16 mm | 62% | 2.8 m/s | 5.8 |
| 2001 | 28.5°C | 22.5°C | 16.6°C | 36.8°C | 12.0°C | 70 mm | 65% | 2.7 m/s | 5.3 |
| 2000 | 24.5°C | 19.6°C | 14.7°C | 29.0°C | 7.7°C | 81 mm | 78% | 2.6 m/s | 5.3 |
| 1999 | 25.9°C | 20.5°C | 15.0°C | 30.6°C | 9.3°C | 59 mm | 67% | 2.9 m/s | 5.1 |
| 1998 | 28.3°C | 22.6°C | 16.9°C | 32.7°C | 9.9°C | 59 mm | 65% | 2.2 m/s | 5.5 |
| 1997 | 25.1°C | 19.6°C | 14.2°C | 30.0°C | 10.4°C | 70 mm | 70% | 2.9 m/s | 4.6 |
| 1996 | 27.7°C | 21.5°C | 15.3°C | 32.3°C | 11.5°C | 29 mm | 66% | 2.2 m/s | 5.8 |
| 1995 | 29.4°C | 23.6°C | 17.8°C | 33.4°C | 11.5°C | 60 mm | 65% | 2.7 m/s | 5.1 |
| 1994 | 25.0°C | 19.5°C | 14.0°C | 29.5°C | 9.1°C | 74 mm | 71% | 2.6 m/s | 5.2 |
| 1993 | 28.1°C | 22.3°C | 16.6°C | 33.0°C | 12.4°C | 47 mm | 65% | 2.3 m/s | 5.6 |
| 1992 ❄️ | 23.1°C | 17.8°C | 12.5°C | 28.5°C | 8.0°C | 112 mm | 77% | 2.8 m/s | 5.7 |
| 1991 | 27.6°C | 21.8°C | 15.9°C | 33.6°C | 10.1°C | 65 mm | 66% | 2.6 m/s | 5.4 |
| 1990 | 26.3°C | 20.8°C | 15.3°C | 29.8°C | 10.9°C | 88 mm | 71% | 2.4 m/s | 4.9 |
| 1989 | 27.0°C | 21.1°C | 15.3°C | 31.4°C | 10.4°C | 47 mm | 67% | 2.8 m/s | 5.3 |
| 1988 | 27.6°C | 22.2°C | 16.8°C | 33.3°C | 8.8°C | 89 mm | 68% | 2.7 m/s | 5.4 |
| 1987 | 26.5°C | 21.2°C | 15.8°C | 32.0°C | 10.0°C | 93 mm | 66% | 3.1 m/s | 4.9 |
| 1986 | 24.6°C | 19.3°C | 13.9°C | 30.6°C | 6.7°C | 74 mm | 69% | 2.7 m/s | 5.6 |
| 1985 🌧️ | 25.5°C | 19.8°C | 14.1°C | 31.3°C | 9.0°C | 125 mm | 69% | 2.6 m/s | 5.4 |
| 1984 | 27.1°C | 21.3°C | 15.5°C | 30.9°C | 9.0°C | 88 mm | 70% | 2.4 m/s | 5.7 |
| 1983 | 27.4°C | 21.6°C | 15.8°C | 30.8°C | 9.9°C | 85 mm | 72% | 2.3 m/s | — |
| 1982 | 24.5°C | 18.7°C | 13.0°C | 30.4°C | 4.7°C | 95 mm | 69% | 2.5 m/s | — |
| 1981 | 26.1°C | 20.7°C | 15.3°C | 29.4°C | 8.0°C | 88 mm | 70% | 2.5 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 27.1°C with lows near 15.9°C (mean 21.5°C), based on 45 years of NASA POWER data.
August averages 63 mm of rainfall in St. Thomas, about average for rainfall. The wettest on record was 125 mm in 1985.
The hottest August reached 36.8°C in 2001. The coldest dipped to 4.7°C in 1982.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 2.3°C. Daytime highs moved from 26.1°C to 28.6°C and overnight lows from 14.7°C to 16.9°C over the same span.
August is one of the warmer months of the year in St. Thomas and about average for rainfall, so plan for around 27.1°C daytime highs and 15.9°C at night.
Not quite — August is the 11th coolest month in St. Thomas, averaging 21.5°C.
For August in St. Thomas, pack light layers you can adjust through the day, with typical highs of 27.1°C and lows of 15.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in August averages 68% — moderately humid.
Average wind speed in August is 2.6 m/s. The windiest August on record averaged 3.1 m/s (1987).
The wettest August on record was 1985 with 125 mm. On average, August sees 63 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. Thomas 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.
