Eureka (MO) Temperature by Month
Eureka, Missouri, United States of America has an average annual maximum temperature of 19°C (66°F), ranging from 5°C (41°F) in January to 31°C (88°F) in July. Below you'll find a full monthly breakdown and a comparison with cities worldwide.
Eureka Monthly Temperatures
The climate in Eureka is dynamic, ranging widely from chilly in winter to very warm in summer. Nights are significantly colder, with lows dropping from 20°C (68°F) in July to -6°C (21°F) in January.
The chart below illustrates the average maximum day and minimum night temperatures in Eureka by month:
From around 4 AM to 6 AM temperatures are at their lowest; by 3 PM they've climbed to their daily peak. July, the warmest month, averages 311 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Eureka vs the United States of America
The map below shows the annual temperature across the United States of America. You can also select individual months if you want to compare a specific time of year.
very warm
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moderate
cold
very cold
Eureka vs World: Temperature Compared
Eureka's average annual maximum temperature is 19°C (66°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.
On the cooler end, Oslo, Norway averages just 10°C (50°F) annually, with pleasant summers but long, cold winters.
Buenos Aires, Argentina averages 23°C (73°F) a year, with hot summers and mild winters — and seasons reversed compared to Europe.
Melbourne, Australia averages 20°C (68°F) annually — known for unpredictable weather, with four seasons sometimes happening in one day.
What Does the Temperature Feel Like in Eureka?
Temperature alone doesn't tell the whole story — humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.
In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.
In Eureka, January is the coolest month, with average highs of 5°C (41°F) and humidity around 72% — considered high. In July, the warmest month, temperatures average 31°C (88°F) with 68% humidity — conditions that feel high. For a full picture, see our humidity page.
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.
Global average temperatures have risen by around 1.2°C since the pre-industrial era, and the effects are visible across many regions. Winters are milder on average, with fewer frost days and less snow in many parts of the world. Heatwaves are more frequent and more intense, and Europe's summers of 2018, 2019, and 2020 all set records.
Summers are also getting drier in some areas, while winter rainfall has increased in others. This contributies to higher river levels and more flooding. In many countries, spring arrives earlier and autumn lasts longer. It has knock-on effects for wildlife, agriculture, and local ecosystems.
For more on Eureka's weather — including monthly rainfall, sunshine hours, and humidity — visit our Eureka climate page.
