Metropolis (IL) Temperature by Month

The average annual maximum temperature in Metropolis, Illinois, United States of America is 20°C (68°F), with daytime highs ranging from 6°C (43°F) in January to 31°C (88°F) in August. This page covers monthly averages, day-night differences, and how Metropolis compares to cities worldwide.

Depending on the time of the year, temperatures range from very warm to cold in Metropolis. At night, minimum temperatures range from 20°C (68°F) in August to -4°C (25°F) in January.

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

Low temperatures are most often recorded between 4 AM and 6 AM, while highs typically occur around 3 PM.

The chart below shows the average temperature throughout the year:

Metropolis's average annual maximum temperature is 20°C (68°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.

Interlaken, Switzerland averages 8°C (46°F) a year, with cold winters and cool summers thanks to its Alpine setting.

New York City, USA averages 17°C (63°F) a year, with hot humid summers and cold winters that bring regular snowfall.

Perth, Australia averages 25°C (77°F) annually, with a classic Mediterranean climate, hot dry summers and mild wet winters.

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 Metropolis's weather, including monthly rainfall, sunshine hours, and humidity, visit our Metropolis climate page.