Bethlehem Weather in August (1981–2025)

📍 40.64°N, 75.37°W •
📊

August at a Glance in Bethlehem

(1981–2025)
Avg High
🔥
28.8°C
Avg Low
❄️
16.9°C
Avg Temp
🌡️
22.9°C
Avg Rain
🌧️
108 mm
Avg Humidity
💧
71%
Avg Wind
🌬️
0.4 m/s
Avg Solar
☀️
5.2
kWh/m²/day
vs Annual
📈
+12.3°C
temp difference
🌡️Warm afternoons🌤️Cool mornings☀️Very sunny🌧️Wet month🍃Light winds😊Comfortable humidity

Bethlehem August Weather Overview

August is one of the warmer months of the year in Bethlehem, with average highs near 28.8°C and lows around 16.9°C (mean 22.9°C). It is about average for rainfall, averaging 108 mm of rainfall and 71% relative humidity across the period.

Bethlehem August Temperature History (1981–2025)

Range

August is one of the warmer months of the year in Bethlehem. Across 45 years of records, the warmest August in Bethlehem was 2022 — when the month averaged 25.7°C — while the coldest was 1982 at 20°C. Typical August days reach 28.8°C with nights near 16.9°C. The long-term trend is warming, about 0.4°C per decade.

1981–1985 vs 2021–2025

Avg Temp21.9°C→23.7°C+1.8°C
Max Temp28.2°C→29.6°C+1.4°C
Min Temp15.6°C→17.8°C+2.2°C

Trend (per decade)

Avg Temp+0.4°C/decade ↗
Max Temp+0.2°C/decade ↗
Min Temp+0.5°C/decade ↗

Distribution of Avg Temp

20.0°C–21.5°C7 yr (16%)
21.5°C–23.0°C17 yr (38%)
23.0°C–24.5°C14 yr (31%)
24.5°C–26.0°C7 yr (16%)

Bethlehem August Rainfall History (1981–2025)

Range

August is about average for rainfall in Bethlehem, averaging 108 mm of rainfall. The wettest August on record was 2011 with 298 mm, while the driest was 1995 at 34 mm.

Bethlehem August Humidity History (1981–2025)

Range

Relative humidity in Bethlehem during August averages 71%. The most humid August was 2018 at 85%, and the least humid was 2002 at 57%.

Bethlehem August Solar History (1981–2025)

Range

August receives about 5.2 kWh/m²/day of solar energy in Bethlehem. The sunniest Augusts were 2015 and 2022 at 5.8 kWh/m²/day, and the cloudiest were 1989, 1990 and 2000 at 4.7.

Bethlehem August Wind History (1981–2025)

Range

Average wind speed in Bethlehem during August is 0.4 m/s. The windiest Augusts were 2023, 2024 and 2025, among others at 0.4 m/s, while the calmest were 1996, 2003 and 2009 at 0.3 m/s.

What August Feels Like in Bethlehem

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

How August Ranks in Bethlehem

🔥2nd warmest month of the year
🌧️5th wettest month of the year
☀️4th sunniest month of the year

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

Explore Bethlehem Weather by Month

Bethlehem August Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp22.0°C22.6°C23.2°C23.0°C23.7°C+1.7°C
Avg High28.1°C28.9°C29.0°C28.7°C29.5°C+1.4°C
Avg Low15.8°C16.3°C17.4°C17.2°C17.9°C+2.1°C
Avg Rain90 mm102 mm107 mm120 mm124 mm+34 mm

Extreme August Records in Bethlehem

🔥Warmest August38.5°C2002
🧊Coldest August4.6°C1982
🌧️Wettest August298 mm2011
🏜️Driest August34 mm1995
🌬️Windiest August0.4 m/s1981

Key Insights for August

✅

August temperatures in Bethlehem have risen by about 1.8°C between 1981–1985 and 2021–2025.

✅

August has ranged from a record low of 4.6°C (1982) to a record high of 38.5°C (2002).

✅

Rainfall in August is about average for rainfall, averaging 108 mm, with a wettest year of 298 mm.

✅

Daytime highs and overnight lows have shifted differently — highs rose about 0.2°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.

Is August a Good Time to Visit Bethlehem?

One of the best times to visit Bethlehem

August is one of the best times to visit Bethlehem. Expect days averaging 28.8°C and nights around 16.9°C (mean 22.9°C) — warmer than Bethlehem's yearly average — with higher rainfall (108 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Bethlehem'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 →

Bethlehem Weather in August — In Depth

☀️ August climate overview

August is one of the warmer months of the year in Bethlehem, with average highs near 28.8°C and lows around 16.9°C (mean 22.9°C). It is about average for rainfall, averaging 108 mm of rainfall and 71% relative humidity across the period.

🌧️ Rain, humidity & wind in August

August averages 108 mm of rainfall in Bethlehem, about average for rainfall compared with the rest of the year. The wettest August on record saw 298 mm (2011), and the driest just 34 mm (1995). Humidity sits around 71% and average wind speed is 0.4 m/s, with solar radiation averaging 5.2 kWh/m²/day.

📈 How August has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 1.8°C. Daytime highs moved from 28.2°C to 29.6°C and overnight lows from 15.6°C to 17.8°C over the same span.
August Weather in Bethlehem, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202529.1°C22.4°C15.8°C34.8°C9.2°C44 mm63%0.4 m/s5.4
202428.8°C23.1°C17.4°C35.6°C10.5°C162 mm75%0.4 m/s4.9
202328.2°C22.8°C17.4°C32.0°C13.0°C114 mm72%0.4 m/s5
2022 🔥32.1°C25.7°C19.3°C37.0°C14.2°C68 mm61%0.4 m/s5.8
202130.0°C24.6°C19.2°C36.3°C14.3°C179 mm76%0.4 m/s4.8
202028.8°C23.6°C18.4°C33.3°C13.3°C180 mm77%0.4 m/s5.3
201928.6°C23.0°C17.5°C33.4°C13.1°C84 mm75%0.4 m/s5.4
201827.8°C23.4°C19.0°C32.6°C13.6°C195 mm85%0.4 m/s4.9
201726.8°C21.4°C16.0°C31.2°C10.9°C131 mm76%0.4 m/s5.1
201630.8°C24.8°C18.9°C34.1°C13.1°C65 mm70%0.4 m/s5.7
201530.2°C23.6°C17.0°C34.6°C13.2°C73 mm62%0.4 m/s5.8
201428.1°C21.7°C15.4°C33.7°C10.8°C72 mm69%0.4 m/s5.2
201327.0°C21.7°C16.3°C31.5°C9.9°C124 mm77%0.4 m/s4.9
201229.5°C23.6°C17.7°C33.4°C12.9°C94 mm68%0.4 m/s5.4
2011 🌧️27.6°C22.2°C16.8°C33.2°C10.1°C298 mm78%0.4 m/s4.9
201030.5°C24.1°C17.7°C35.4°C12.1°C65 mm65%0.4 m/s4.9
200927.3°C22.7°C18.0°C32.4°C12.0°C202 mm83%0.3 m/s5.1
200828.6°C21.9°C15.3°C31.4°C11.0°C58 mm66%0.4 m/s5.7
200730.0°C23.7°C17.4°C35.9°C12.6°C127 mm69%0.4 m/s5
200628.2°C22.7°C17.1°C32.5°C11.0°C95 mm74%0.4 m/s5.4
200531.3°C25.2°C19.2°C37.4°C14.0°C63 mm67%0.4 m/s4.8
200426.5°C21.3°C16.2°C30.9°C10.0°C155 mm83%0.4 m/s4.9
200327.5°C22.7°C18.0°C32.7°C10.1°C132 mm83%0.3 m/s4.8
200231.9°C25.2°C18.5°C38.5°C13.2°C56 mm57%0.4 m/s5.4
200131.3°C24.7°C18.1°C38.3°C14.6°C93 mm64%0.4 m/s5.1
200027.2°C21.7°C16.3°C31.5°C8.8°C88 mm75%0.4 m/s4.7
199930.4°C23.6°C16.9°C36.7°C11.8°C98 mm59%0.4 m/s5.3
199829.7°C23.4°C17.0°C32.8°C9.9°C96 mm68%0.4 m/s5.4
199727.7°C21.5°C15.3°C33.5°C11.0°C127 mm67%0.4 m/s5.2
199627.8°C21.9°C16.1°C32.0°C11.7°C65 mm76%0.3 m/s5.4
199532.2°C24.6°C17.0°C36.0°C11.9°C34 mm58%0.4 m/s5.6
199426.1°C20.5°C14.8°C31.4°C8.8°C165 mm79%0.4 m/s4.9
199330.2°C23.7°C17.2°C35.1°C11.4°C96 mm67%0.4 m/s5.2
199227.4°C21.1°C14.8°C33.0°C9.7°C71 mm69%0.4 m/s5.3
199130.2°C23.6°C17.1°C36.1°C13.7°C109 mm66%0.4 m/s5.4
199027.6°C22.0°C16.4°C33.0°C12.2°C164 mm76%0.4 m/s4.7
198926.6°C21.5°C16.3°C30.6°C10.6°C68 mm78%0.4 m/s4.7
198829.8°C23.6°C17.3°C36.3°C9.2°C97 mm68%0.4 m/s5.1
198729.1°C22.6°C16.0°C34.8°C9.2°C117 mm67%0.4 m/s5
198626.3°C20.6°C14.9°C30.4°C5.5°C136 mm74%0.4 m/s5.3
198528.0°C22.0°C16.0°C34.4°C11.6°C77 mm69%0.4 m/s5.2
198426.6°C21.4°C16.3°C30.4°C8.1°C82 mm82%0.4 m/s5.7
198330.9°C23.9°C16.9°C36.2°C9.5°C74 mm64%0.4 m/s—
1982 ❄️26.5°C20.0°C13.6°C31.9°C4.6°C100 mm69%0.4 m/s—
198128.9°C22.0°C15.1°C32.0°C8.9°C61 mm64%0.4 m/s—

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

Other Cities in Pennsylvania

Bethlehem August Weather — FAQ

What is the average temperature in Bethlehem in August?▼

The average high in August is around 28.8°C with lows near 16.9°C (mean 22.9°C), based on 45 years of NASA POWER data.

Does it rain a lot in Bethlehem in August?▼

August averages 108 mm of rainfall in Bethlehem, about average for rainfall. The wettest on record was 298 mm in 2011.

What was the hottest August on record in Bethlehem?▼

The hottest August reached 38.5°C in 2002. The coldest dipped to 4.6°C in 1982.

Has August in Bethlehem gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 1.8°C. Daytime highs moved from 28.2°C to 29.6°C and overnight lows from 15.6°C to 17.8°C over the same span.

Is August a good time to visit Bethlehem?▼

August is one of the warmer months of the year in Bethlehem and about average for rainfall, so plan for around 28.8°C daytime highs and 16.9°C at night.

Is August the coldest month in Bethlehem?▼

Not quite — August is the 11th coolest month in Bethlehem, averaging 22.9°C.

What should I pack for Bethlehem in August?▼

For August in Bethlehem, pack light layers you can adjust through the day, with typical highs of 28.8°C and lows of 16.9°C. Bring an umbrella or light rain jacket too.

Is Bethlehem humid in August?▼

Relative humidity in August averages 71% — moderately humid.

How windy is Bethlehem in August?▼

Average wind speed in August is 0.4 m/s. The windiest August on record averaged 0.4 m/s (1981).

Which August had the most rainfall in Bethlehem?▼

The wettest August on record was 2011 with 298 mm. On average, August sees 108 mm.

Where does this August 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.

Other Pennsylvania cities

Explore how the weather in Bethlehem 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.