Streator (IL) Temperature by Month

Streator in Illinois, United States of America sees significant seasonal temperature differences, with daytime highs between 0°C (32°F) in January and 29°C (84°F) in July, averaging 16°C (61°F) annually. Explore the full monthly breakdown below.

The weather in Streator experiences significant differences between warm and cold seasons, with big shifts in temperature. At night, minimum temperatures range from 18°C (64°F) in July to -9°C (16°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Streator 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:

Streator'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:

Lisbon, Portugal averages 21°C (70°F) annually, warm summers, mild winters, and rain mainly in the cooler months.

On the cooler end, Oslo, Norway averages just 10°C (50°F) annually, with pleasant summers but long, cold winters.

Seoul, South Korea averages 18°C (64°F) a year, with four clear seasons, cold winters, and hot humid summers.

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.

For cities and regions with significant elevation, altitude is one of the biggest factors shaping local temperatures. As a rule of thumb, temperatures fall by around 6°C for every 1,000 metres gained, so a city at 2,000 metres will typically be around 12°C cooler than a city at sea level in the same region. Higher ground also tends to see more dramatic day-to-night temperature swings, since thinner air loses heat faster after sunset.

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