Petaluma (CA) Temperature by Month
Petaluma in California, United States of America sees significant seasonal temperature differences, with daytime highs between 14°C (57°F) in January and 28°C (82°F) in July, averaging 22°C (72°F) annually. Explore the full monthly breakdown below.
Petaluma Monthly Temperatures
The climate in Petaluma is known for significant temperature differences throughout the year. At night, this contrast is just as clear, with lows ranging from 11°C (52°F) in July to 3°C (37°F) in January.
The chart below illustrates the average maximum day and minimum night temperatures in Petaluma by month:
The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM. July, the city's warmest month, gets 306 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Petaluma 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.
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Petaluma vs World: Temperature Compared
Petaluma's average annual maximum temperature is 22°C (72°F). To put that in context, here's how it compares to a few well-known destinations:
Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.
Glasgow, Scotland averages 13°C (55°F) a year — mild but often grey, with cold winters and rarely hot summers.
Boston, USA averages 16°C (61°F) annually, with four distinct seasons and cold winters that rival northern Europe.
Brisbane, Australia averages 26°C (79°F) a year, with warm winters and hot, humid summers.
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.
Seasonal temperature shifts influence more than just how warm it feels — they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.
Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in Petaluma this rarely lasts long on the ground.
For more on Petaluma's weather — including monthly rainfall, sunshine hours, and humidity — visit our Petaluma climate page.
