Heidelberg Temperature by Month

Heidelberg in Baden-Württemberg, Germany sees significant seasonal temperature differences, with daytime highs between 5°C (41°F) in January and 26°C (79°F) in July, averaging 16°C (61°F) annually. Explore the full monthly breakdown below.

Depending on the time of the year, temperatures range from warm to cold in Heidelberg. Nighttime lows follow the same pattern, ranging from 15°C (59°F) to -1°C (30°F).

The chart below illustrates the average maximum day and minimum night temperatures in Heidelberg by month:

Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating. July, the warmest month of the year, receives 237 hours of sunshine.

The chart below shows the average temperature throughout the year:

Heidelberg's average annual maximum temperature is 16°C (61°F). To put that in context, here's how it compares to a few well-known destinations:

Rome, Italy averages 20°C (68°F) annually, with reliably warm summers and comfortable winters.

Reykjavík, Iceland averages 9°C (48°F) a year, mild summers by Icelandic standards, but cold winters and frequent wind.

Beijing, China averages 20°C (68°F) annually, but with big seasonal swings, very cold winters and hot summers.

Melbourne, Australia averages 20°C (68°F) annually, known for unpredictable weather, with four seasons sometimes happening in one day.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round, large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.

For more on Heidelberg's weather, including monthly rainfall, sunshine hours, and humidity, visit our Heidelberg climate page.