ClimateAverages

Bethlehem Climate

Pennsylvania, United States of America · population 74,892 · 642 weather stations within 200 km · records 1750 to 2025

Average annual daytime high
16.2°C
Warmest month · July
29.1°C
Typical daytime high
Coldest month · January
-7.0°C
Typical overnight low

Bethlehem has an average annual daytime high of 16.2°C, based on the 1951 to 1980 baseline. Its warmest month is July, when highs typically reach 29.1°C, and its coldest is January, with overnight lows near -7.0°C.

Month by month averages

MonthAvg highAvg low
January2.2°C-7.0°CColdest
February3.8°C-6.4°C
March9.0°C-1.8°C
April16.2°C3.5°C
May22.0°C8.9°C
June26.7°C13.9°C
July29.1°C16.4°CWarmest
August28.2°C15.9°C
September24.4°C11.8°C
October18.0°C5.4°C
November11.0°C0.8°C
December4.3°C-4.7°C

Temperature range across the year

-9°1°11°21°31°JanFebMarAprMayJunJulAugSepOctNovDec
Daytime high Overnight low
Hottest year on record
2011
+2.3°C vs. 1951–1980
Coldest year on record
1783
-2.5°C vs. 1951–1980

These figures reflect annual averages, not single-day records. Daily observations are outside this dataset's precision.

Is Bethlehem getting hotter?

Since 1900, Bethlehem's average temperature has risen by +2.0°C. Compared to the earliest station records that begin in 1750, warming totals +2.6°C.

9.7°10.4°11.0°11.7°12.3°1951–1980 baseline190019251950197520002025

20-year smoothed annual temperature reconstructed from station anomalies. Dashed line: 1951–1980 baseline.

Best time to visit
April to October

Daytime highs sit within a comfortable 15°C to 26°C range.

FAQ

What is the average temperature in Bethlehem?

Bethlehem's average annual daytime high is 16.2°C, based on the 1951 to 1980 baseline period. The warmest month is July, with highs averaging 29.1°C, and the coldest is January, with lows averaging -7.0°C.

What is the warmest month in Bethlehem?

July is the warmest month in Bethlehem, with typical daytime highs of 29.1°C.

What is the hottest year on record for Bethlehem?

2011 is the hottest year on record for Bethlehem, running +2.3°C above the 1951 to 1980 baseline.

Is Bethlehem getting hotter?

Yes. Since 1900, Bethlehem has warmed by roughly +2.0°C.

When is the best time to visit Bethlehem?

April to October typically offers the most comfortable daytime highs, in the 15°C to 26°C range.

Nearby cities

Baseline period 1951 to 1980. Monthly averages are the mean of station observations weighted by proximity. Warming trend is the 20-year smoothed anomaly against that baseline.