St. Thomas Weather in May (1981–2025)

📍 42.77°N, 81.18°W •
📊

May at a Glance in St. Thomas

(1981–2025)
Avg High
🔥
19.2°C
Avg Low
❄️
7.3°C
Avg Temp
🌡️
13.3°C
Avg Rain
🌧️
65 mm
Avg Humidity
💧
73%
Avg Wind
🌬️
3.3 m/s
Avg Solar
☀️
5.6
kWh/m²/day
vs Annual
📈
+4.7°C
temp difference
🌤️Mild afternoons❄️Cold mornings☀️Very sunny🌧️Wet month💨Breezy😊Comfortable humidity

St. Thomas May Weather Overview

May is one of the warmer months of the year in St. Thomas, with average highs near 19.2°C and lows around 7.3°C (mean 13.3°C). It is about average for rainfall, averaging 65 mm of rainfall and 73% relative humidity across the period.

St. Thomas May Temperature History (1981–2025)

Range

May is one of the warmer months of the year in St. Thomas. Across 45 years of records, the warmest May in St. Thomas was 1998 — when the month averaged 16.8°C — while the coldest was 1997 at 8.6°C. Typical May days reach 19.2°C with nights near 7.3°C. The long-term trend is warming, about 0.4°C per decade.

1981–1985 vs 2021–2025

Avg Temp12.1°C→14.8°C+2.7°C
Max Temp17.7°C→21.1°C+3.4°C
Min Temp6.4°C→8.4°C+2°C

Trend (per decade)

Avg Temp+0.4°C/decade ↗
Max Temp+0.5°C/decade ↗
Min Temp+0.4°C/decade ↗

Distribution of Avg Temp

8.0°C–10.3°C4 yr (9%)
10.3°C–12.5°C13 yr (29%)
12.5°C–14.8°C17 yr (38%)
14.8°C–17.0°C11 yr (24%)

St. Thomas May Rainfall History (1981–2025)

Range

May is about average for rainfall in St. Thomas, averaging 65 mm of rainfall. The wettest May on record was 2000 with 147 mm, while the driest was 2021 at 20 mm.

St. Thomas May Humidity History (1981–2025)

Range

Relative humidity in St. Thomas during May averages 73%. The most humid May was 2004 at 82%, and the least humid was 2023 at 58%.

St. Thomas May Solar History (1981–2025)

Range

May receives about 5.6 kWh/m²/day of solar energy in St. Thomas. The sunniest May was 2023 at 6.5 kWh/m²/day, and the cloudiest were 1984 and 2019 at 4.7.

St. Thomas May Wind History (1981–2025)

Range

Average wind speed in St. Thomas during May is 3.3 m/s. The windiest May was 1997 at 4 m/s, while the calmest was 1982 at 2.6 m/s.

What May Feels Like in St. Thomas

🌅
Cold
Morning
🌞
Mild
Afternoon
🌆
Cool
Evening
Rain chanceModerate
Outdoor comfort★★★☆☆

How May Ranks in St. Thomas

🔥5th warmest month of the year
🌧️4th wettest month of the year
☀️3rd sunniest month of the year

Ranked against the other 11 months using 1981–2025 averages.

Explore St. Thomas Weather by Month

St. Thomas May Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp12.8°C12.8°C12.5°C14.1°C14.4°C+1.6°C
Avg High18.6°C18.7°C18.5°C20.0°C20.6°C+2°C
Avg Low7.0°C6.8°C6.6°C8.2°C8.1°C+1.1°C
Avg Rain73 mm60 mm75 mm70 mm35 mm-38 mm

Extreme May Records in St. Thomas

🔥Warmest May33.0°C2006
🧊Coldest May-2.9°C1983
🌧️Wettest May147 mm2000
🏜️Driest May20 mm2021
🌬️Windiest May4 m/s1997

Key Insights for May

✅

May temperatures in St. Thomas have risen by about 2.7°C between 1981–1985 and 2021–2025.

✅

May has ranged from a record low of -2.9°C (1983) to a record high of 33°C (2006).

✅

Rainfall in May is about average for rainfall, averaging 65 mm, with a wettest year of 147 mm.

Is May a Good Time to Visit St. Thomas?

A good time to visit St. Thomas

May is a good time to visit St. Thomas, with days averaging 19.2°C and nights around 7.3°C (mean 13.3°C, warmer than St. Thomas's yearly average) and moderate rainfall. July and August are marginally more temperate, but May still suits most travellers.

See St. Thomas's complete weather history All 12 months side by side, 1981–2025 records, annual trends and long-term averages in one place. View full history →

St. Thomas Weather in May — In Depth

☀️ May climate overview

May is one of the warmer months of the year in St. Thomas, with average highs near 19.2°C and lows around 7.3°C (mean 13.3°C). It is about average for rainfall, averaging 65 mm of rainfall and 73% relative humidity across the period.

🌧️ Rain, humidity & wind in May

May averages 65 mm of rainfall in St. Thomas, about average for rainfall compared with the rest of the year. The wettest May on record saw 147 mm (2000), and the driest just 20 mm (2021). Humidity sits around 73% and average wind speed is 3.3 m/s, with solar radiation averaging 5.6 kWh/m²/day.

📈 How May has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 2.7°C. Daytime highs moved from 17.7°C to 21.1°C and overnight lows from 6.4°C to 8.4°C over the same span.
May Weather in St. Thomas, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202519.0°C13.5°C7.9°C28.4°C1.6°C39 mm70%3.9 m/s5.1
202423.1°C16.7°C10.3°C29.4°C4.9°C52 mm67%3.1 m/s5.9
202321.4°C14.2°C7.0°C31.6°C1.2°C21 mm58%2.9 m/s6.5
202221.6°C15.5°C9.3°C30.9°C2.4°C47 mm67%3.5 m/s5.7
202120.3°C13.9°C7.4°C30.7°C-0.9°C20 mm59%3.1 m/s5.9
202018.0°C12.3°C6.6°C30.9°C-2.9°C28 mm70%3.6 m/s5.6
201917.9°C12.0°C6.1°C24.9°C0.3°C69 mm80%3.3 m/s4.7
201822.6°C15.8°C9.0°C30.8°C0.9°C72 mm75%3.1 m/s5.8
201716.9°C12.0°C7.0°C26.6°C-0.7°C98 mm78%3.8 m/s5.5
201619.1°C13.3°C7.6°C28.7°C0.9°C39 mm73%2.9 m/s6
201521.1°C14.9°C8.8°C27.2°C1.0°C71 mm74%3.1 m/s5.6
201418.7°C13.1°C7.5°C25.3°C-0.5°C75 mm78%3 m/s5.4
201319.6°C13.8°C8.0°C26.2°C-0.4°C93 mm76%3.4 m/s6.2
201223.1°C16.5°C9.8°C31.0°C2.8°C61 mm66%2.9 m/s6.3
201119.1°C13.8°C8.6°C29.4°C1.4°C75 mm80%3.3 m/s4.9
201021.5°C15.5°C9.5°C31.4°C-0.9°C45 mm68%3.5 m/s5.7
200919.8°C13.0°C6.3°C26.1°C-0.6°C41 mm66%3.6 m/s6.1
200817.8°C11.7°C5.6°C25.1°C0.3°C41 mm68%3.7 m/s5.6
200722.1°C15.0°C8.0°C32.3°C1.6°C30 mm61%3.1 m/s6.1
200620.0°C14.3°C8.6°C33.0°C1.5°C47 mm68%3.4 m/s5.6
200517.7°C11.7°C5.7°C24.4°C-0.3°C31 mm69%2.9 m/s6
200418.1°C12.4°C6.7°C25.5°C-2.0°C112 mm82%3.3 m/s5.2
200317.1°C11.7°C6.2°C22.3°C1.0°C105 mm79%3.7 m/s5
200214.8°C9.3°C3.7°C23.5°C-2.2°C90 mm79%3.7 m/s5.3
200118.4°C13.0°C7.6°C25.4°C0.0°C104 mm78%3.3 m/s5.3
2000 🌧️18.7°C13.3°C8.0°C25.6°C3.0°C147 mm80%3.5 m/s5
199920.7°C14.4°C8.2°C29.0°C3.2°C49 mm69%3.3 m/s5.8
1998 🔥23.1°C16.8°C10.5°C30.3°C4.1°C29 mm69%3.1 m/s6.1
1997 ❄️14.1°C8.6°C3.1°C20.6°C-2.0°C98 mm77%4 m/s5
199617.1°C11.3°C5.5°C25.8°C-1.5°C61 mm73%3.3 m/s5.5
199518.5°C12.6°C6.7°C25.4°C0.4°C60 mm69%3.3 m/s5.4
199417.5°C11.2°C4.9°C28.7°C-0.6°C61 mm71%3.4 m/s5.8
199318.4°C12.4°C6.3°C27.0°C1.7°C48 mm72%3.4 m/s5.4
199219.2°C12.6°C6.1°C27.4°C1.3°C38 mm68%2.9 m/s5.9
199121.7°C16.2°C10.7°C28.2°C0.9°C69 mm77%3.1 m/s5.7
199017.1°C11.5°C5.8°C22.6°C0.5°C91 mm72%3.7 m/s5.4
198917.7°C12.4°C7.1°C25.8°C0.3°C69 mm74%3.4 m/s5.1
198820.8°C14.2°C7.7°C30.2°C1.7°C56 mm70%3.1 m/s6.2
198721.4°C14.8°C8.2°C30.0°C-0.4°C54 mm70%3.2 m/s6.4
198619.0°C13.7°C8.4°C27.0°C-2.9°C80 mm79%3.3 m/s5.9
198519.2°C13.3°C7.4°C25.8°C1.6°C68 mm76%3.5 m/s6.3
198415.1°C9.9°C4.6°C23.0°C-1.6°C79 mm80%3.7 m/s4.7
198315.4°C9.8°C4.2°C20.4°C-2.9°C129 mm79%3.7 m/s—
198221.0°C15.2°C9.4°C25.9°C2.6°C69 mm78%2.6 m/s—
198117.8°C12.1°C6.3°C25.4°C-1.2°C50 mm73%3 m/s—

Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.

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St. Thomas May Weather — FAQ

What is the average temperature in St. Thomas in May?▼

The average high in May is around 19.2°C with lows near 7.3°C (mean 13.3°C), based on 45 years of NASA POWER data.

Does it rain a lot in St. Thomas in May?▼

May averages 65 mm of rainfall in St. Thomas, about average for rainfall. The wettest on record was 147 mm in 2000.

What was the hottest May on record in St. Thomas?▼

The hottest May reached 33°C in 2006. The coldest dipped to -2.9°C in 1983.

Has May in St. Thomas gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 2.7°C. Daytime highs moved from 17.7°C to 21.1°C and overnight lows from 6.4°C to 8.4°C over the same span.

Is May a good time to visit St. Thomas?▼

May is one of the warmer months of the year in St. Thomas and about average for rainfall, so plan for around 19.2°C daytime highs and 7.3°C at night.

Is May the coldest month in St. Thomas?▼

Not quite — May is the 8th coolest month in St. Thomas, averaging 13.3°C.

What should I pack for St. Thomas in May?▼

For May in St. Thomas, pack warm layers and a jacket for chilly mornings, with typical highs of 19.2°C and lows of 7.3°C. Bring an umbrella or light rain jacket too.

Is St. Thomas humid in May?▼

Relative humidity in May averages 73% — moderately humid.

How windy is St. Thomas in May?▼

Average wind speed in May is 3.3 m/s. The windiest May on record averaged 4 m/s (1997).

Which May had the most rainfall in St. Thomas?▼

The wettest May on record was 2000 with 147 mm. On average, May sees 65 mm.

Where does this May weather data come from?▼

All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.

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Explore how the weather in St. Thomas behaves each May, 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 May specifically, along with year-by-year records and how the month has changed over the decades.