Coatesville Weather in May (1981–2025)

📍 39.97°N, 75.83°W •
📊

May at a Glance in Coatesville

(1981–2025)
Avg High
🔥
21.8°C
Avg Low
❄️
10.2°C
Avg Temp
🌡️
16.0°C
Avg Rain
🌧️
105 mm
Avg Humidity
💧
78%
Avg Wind
🌬️
0.5 m/s
Avg Solar
☀️
5.6
kWh/m²/day
vs Annual
📈
+4.4°C
temp difference
🌤️Mild afternoons🌤️Cool mornings☀️Very sunny🌧️Wet month🍃Light winds💦Humid air

Coatesville May Weather Overview

May is one of the warmer months of the year in Coatesville, with average highs near 21.8°C and lows around 10.2°C (mean 16°C). It is about average for rainfall, averaging 105 mm of rainfall and 78% relative humidity across the period.

Coatesville May Temperature History (1981–2025)

Range

May is one of the warmer months of the year in Coatesville. Across 45 years of records, the warmest May in Coatesville was 2004 — when the month averaged 19.1°C — while the coldest was 1997 at 13.4°C. Typical May days reach 21.8°C with nights near 10.2°C. The long-term trend is warming, about 0.4°C per decade.

1981–1985 vs 2021–2025

Avg Temp15.3°C→16.6°C+1.3°C
Max Temp21.3°C→22.4°C+1.1°C
Min Temp9.4°C→10.9°C+1.5°C

Trend (per decade)

Avg Temp+0.4°C/decade ↗
Max Temp+0.3°C/decade ↗
Min Temp+0.5°C/decade ↗

Distribution of Avg Temp

13.0°C–14.8°C11 yr (24%)
14.8°C–16.5°C21 yr (47%)
16.5°C–18.3°C8 yr (18%)
18.3°C–20.0°C5 yr (11%)

Coatesville May Rainfall History (1981–2025)

Range

May is about average for rainfall in Coatesville, averaging 105 mm of rainfall. The wettest May on record was 1989 with 216 mm, while the driest was 2023 at 10 mm.

Coatesville May Humidity History (1981–2025)

Range

Relative humidity in Coatesville during May averages 78%. The most humid May was 2003 at 84%, and the least humid was 2023 at 70%.

Coatesville May Solar History (1981–2025)

Range

May receives about 5.6 kWh/m²/day of solar energy in Coatesville. The sunniest May was 2007 at 6.8 kWh/m²/day, and the cloudiest was 2003 at 3.7.

Coatesville May Wind History (1981–2025)

Range

Average wind speed in Coatesville during May is 0.5 m/s. The windiest May was 1997 at 0.6 m/s, while the calmest were 2018, 2023 and 2024, among others at 0.4 m/s.

What May Feels Like in Coatesville

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

How May Ranks in Coatesville

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

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

Explore Coatesville Weather by Month

Coatesville May Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp15.4°C15.3°C15.9°C17.2°C16.3°C+0.9°C
Avg High21.3°C21.3°C21.8°C22.8°C22.0°C+0.7°C
Avg Low9.5°C9.3°C10.1°C11.7°C10.5°C+1°C
Avg Rain130 mm97 mm91 mm108 mm96 mm-33 mm

Extreme May Records in Coatesville

🔥Warmest May34.0°C2011
🧊Coldest May-0.2°C2020
🌧️Wettest May216 mm1989
🏜️Driest May10 mm2023
🌬️Windiest May0.6 m/s1997

Key Insights for May

✅

May temperatures in Coatesville have risen by about 1.3°C between 1981–1985 and 2021–2025.

✅

May has ranged from a record low of -0.2°C (2020) to a record high of 34°C (2011).

✅

Rainfall in May is about average for rainfall, averaging 105 mm, with a wettest year of 216 mm.

✅

Daytime highs and overnight lows have shifted differently — highs rose about 0.3°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.

Is May a Good Time to Visit Coatesville?

A good time to visit Coatesville

May is a good time to visit Coatesville, with days averaging 21.8°C and nights around 10.2°C (mean 16°C, warmer than Coatesville's yearly average) and higher rainfall. June and August are marginally more temperate, but May still suits most travellers.

See Coatesville'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 →

Coatesville Weather in May — In Depth

☀️ May climate overview

May is one of the warmer months of the year in Coatesville, with average highs near 21.8°C and lows around 10.2°C (mean 16°C). It is about average for rainfall, averaging 105 mm of rainfall and 78% relative humidity across the period.

🌧️ Rain, humidity & wind in May

May averages 105 mm of rainfall in Coatesville, about average for rainfall compared with the rest of the year. The wettest May on record saw 216 mm (1989), and the driest just 10 mm (2023). Humidity sits around 78% and average wind speed is 0.5 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 1.3°C. Daytime highs moved from 21.3°C to 22.4°C and overnight lows from 9.4°C to 10.9°C over the same span.
May Weather in Coatesville, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202522.3°C17.0°C11.7°C27.9°C6.4°C196 mm78%0.5 m/s5.1
202423.1°C18.0°C12.9°C29.3°C5.5°C75 mm82%0.4 m/s5
202322.0°C15.4°C8.8°C28.1°C2.7°C10 mm70%0.4 m/s6.4
202222.8°C17.1°C11.4°C32.0°C5.2°C132 mm79%0.5 m/s5.4
202121.7°C15.7°C9.8°C30.4°C3.2°C98 mm74%0.5 m/s5.8
202019.9°C14.3°C8.7°C27.5°C-0.2°C67 mm76%0.5 m/s5.7
201922.6°C17.4°C12.2°C28.6°C5.0°C168 mm82%0.5 m/s5.4
201824.5°C18.9°C13.3°C29.9°C4.4°C149 mm82%0.4 m/s5.1
201721.0°C15.6°C10.2°C31.5°C3.4°C135 mm77%0.5 m/s5.1
201620.4°C15.3°C10.2°C30.0°C2.4°C135 mm81%0.4 m/s4.7
201524.8°C18.7°C12.6°C30.5°C6.4°C39 mm76%0.4 m/s6.3
201421.9°C16.2°C10.4°C27.4°C5.2°C100 mm80%0.4 m/s5.4
201321.7°C16.0°C10.3°C31.8°C1.1°C77 mm78%0.5 m/s5.9
201224.4°C18.9°C13.3°C32.5°C6.3°C105 mm79%0.4 m/s5.5
201123.0°C17.8°C12.6°C34.0°C5.0°C92 mm82%0.4 m/s5.6
201023.3°C17.4°C11.6°C31.2°C1.3°C81 mm77%0.5 m/s5.9
200921.8°C16.4°C11.1°C27.6°C3.3°C133 mm79%0.4 m/s5
200820.4°C14.5°C8.6°C27.4°C2.3°C119 mm78%0.5 m/s5.4
200723.2°C16.8°C10.4°C30.2°C2.5°C48 mm75%0.4 m/s6.8
200622.5°C16.3°C10.1°C32.8°C4.3°C57 mm72%0.5 m/s6.3
200519.4°C13.5°C7.7°C25.4°C1.3°C40 mm77%0.5 m/s5.7
2004 🔥24.5°C19.1°C13.7°C29.5°C4.4°C103 mm81%0.4 m/s5.8
200319.2°C14.2°C9.3°C26.0°C3.6°C115 mm84%0.4 m/s3.7
200222.4°C15.7°C9.0°C30.2°C1.8°C107 mm71%0.5 m/s6.4
200122.8°C16.4°C10.0°C30.9°C2.5°C97 mm74%0.4 m/s5.8
200022.2°C16.4°C10.7°C31.7°C2.7°C95 mm79%0.4 m/s5.5
199923.0°C16.3°C9.6°C32.3°C3.7°C64 mm72%0.5 m/s5.9
199822.6°C17.2°C11.8°C33.1°C3.9°C136 mm82%0.4 m/s5.6
1997 ❄️19.5°C13.4°C7.3°C28.0°C1.3°C79 mm73%0.6 m/s6
199619.8°C14.2°C8.6°C30.1°C2.1°C91 mm80%0.4 m/s5.3
199521.1°C15.1°C9.1°C28.1°C2.5°C93 mm76%0.5 m/s5.3
199419.9°C13.7°C7.5°C28.8°C2.9°C92 mm77%0.5 m/s6
199321.9°C16.0°C10.1°C27.9°C5.0°C56 mm78%0.4 m/s5.8
199220.2°C14.0°C7.9°C30.2°C1.7°C113 mm76%0.5 m/s5.6
199124.8°C18.6°C12.4°C31.4°C4.8°C64 mm78%0.4 m/s6.5
199019.7°C14.2°C8.7°C25.8°C3.8°C181 mm78%0.5 m/s5.1
1989 🌧️20.1°C14.9°C9.6°C28.1°C4.1°C216 mm82%0.5 m/s4.8
198821.4°C15.6°C9.9°C29.3°C2.6°C151 mm82%0.4 m/s5.3
198721.3°C15.4°C9.4°C31.1°C2.0°C83 mm81%0.4 m/s5.6
198622.6°C16.3°C10.0°C30.2°C0.5°C39 mm76%0.4 m/s6.4
198522.6°C16.4°C10.3°C28.3°C2.0°C140 mm74%0.5 m/s5.8
198419.6°C14.3°C9.0°C26.8°C2.7°C177 mm82%0.5 m/s4.4
198320.0°C14.2°C8.5°C25.2°C0.8°C149 mm81%0.5 m/s—
198222.4°C16.4°C10.5°C27.6°C5.1°C98 mm79%0.4 m/s—
198121.9°C15.2°C8.6°C28.6°C1.4°C112 mm74%0.5 m/s—

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

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Coatesville May Weather — FAQ

What is the average temperature in Coatesville in May?▼

The average high in May is around 21.8°C with lows near 10.2°C (mean 16°C), based on 45 years of NASA POWER data.

Does it rain a lot in Coatesville in May?▼

May averages 105 mm of rainfall in Coatesville, about average for rainfall. The wettest on record was 216 mm in 1989.

What was the hottest May on record in Coatesville?▼

The hottest May reached 34°C in 2011. The coldest dipped to -0.2°C in 2020.

Has May in Coatesville 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 1.3°C. Daytime highs moved from 21.3°C to 22.4°C and overnight lows from 9.4°C to 10.9°C over the same span.

Is May a good time to visit Coatesville?▼

May is one of the warmer months of the year in Coatesville and about average for rainfall, so plan for around 21.8°C daytime highs and 10.2°C at night.

Is May the coldest month in Coatesville?▼

Not quite — May is the 8th coolest month in Coatesville, averaging 16°C.

What should I pack for Coatesville in May?▼

For May in Coatesville, pack light layers you can adjust through the day, with typical highs of 21.8°C and lows of 10.2°C. Bring an umbrella or light rain jacket too.

Is Coatesville humid in May?▼

Relative humidity in May averages 78% — quite humid.

How windy is Coatesville in May?▼

Average wind speed in May is 0.5 m/s. The windiest May on record averaged 0.6 m/s (1997).

Which May had the most rainfall in Coatesville?▼

The wettest May on record was 1989 with 216 mm. On average, May sees 105 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 Coatesville 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.