Monte Rio (CA) Temperature by Month

Monte Rio in California, United States of America sees significant seasonal temperature differences, with daytime highs between 14°C (57°F) in December and 27°C (81°F) in July, averaging 21°C (70°F) annually. Explore the full monthly breakdown below.

Visitors to Monte Rio will encounter a climate influenced by big temperature differences across the year. Nighttime temperatures range from 11°C (52°F) in July to 4°C (39°F) in December.

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

The coolest part of the day is typically between 4 AM and 6 AM, while 3 PM is usually the warmest, when solar heating is at its peak. July, the city's warmest month, averages 306 hours of sunshine.

The chart below shows the average temperature throughout the year:

Monte Rio's average annual maximum temperature is 21°C (70°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.

Queenstown, New Zealand averages 10°C (50°F) annually, remember seasons are flipped, so its coldest months fall in June and July.

Buenos Aires, Argentina averages 23°C (73°F) a year, with hot summers and mild winters, and seasons reversed compared to Europe.

Tokyo, Japan averages 21°C (70°F) a year, with hot summers, cool winters, and a well-defined cherry blossom spring.

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