Vacaville (CA) Temperature by Month
Vacaville, California, United States of America has an average annual maximum temperature of 24°C (75°F), ranging from 14°C (57°F) in January to 34°C (93°F) in July. Below you'll find a full monthly breakdown and a comparison with cities worldwide.
Vacaville Monthly Temperatures
Visitors to Vacaville will encounter a climate influenced by big temperature differences across the year. Nighttime temperatures range from 15°C (59°F) in July to 3°C (37°F) in January.
The chart below illustrates the average maximum day and minimum night temperatures in Vacaville by month:
Low temperatures are most often recorded between 4 AM and 6 AM, while highs typically occur around 3 PM. July, the city's warmest month, sees 440 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Vacaville 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
warm
pleasant
moderate
cold
very cold
Vacaville vs World: Temperature Compared
Vacaville's average annual maximum temperature is 24°C (75°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.
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.
Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.
What Does the Temperature Feel Like in Vacaville?
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 Vacaville, January is the coolest month, with average highs of 15°C (59°F) and humidity around 83% — considered very high. In July, the warmest month, temperatures average 34°C (93°F) with 53% humidity — conditions that feel moderate. 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 Vacaville's weather — including monthly rainfall, sunshine hours, and humidity — visit our Vacaville climate page.
