Vallejo (CA) Temperatures: Monthly Averages and Year-Round Insights
On this page, we’ll explore Vallejo’s temperature statistics in detail, including day and night variations and monthly averages. We’ll also compare the annual temperature to other cities in the United States of America.
Monthly Temperature Averages
Visitors to Vallejo can expect significant temperature changes throughout the year. Average maximum daytime temperatures reach a comfortable 27°C in September. In January, the coolest month of the year, temperatures drop to a moderate 14°C. At night, minimum temperatures can drop even lower, averaging around 4°C.
The chart below illustrates the average maximum day and minimum night temperatures in Vallejo by month:
The lowest temperatures typically occur between 4 AM and 6 AM, while the peak temperatures are generally observed around 3 PM, coinciding with the sun’s strongest heating effect. September, the city’s warmest month, enjoys 270 hours of sunshine.
The chart below shows the average temperature throughout the year:
January, the city’s coldest month, receives about 74 mm of rainfall spread over roughly 9 days. For more information, please visit our Vallejo Precipitation page.
Annual Temperatures in the United States of America Compared
The map below shows the annual temperature across the United States of America. You can also select the different months in case you are interested in a specific month.
very warm
warm
pleasant
moderate
cold
very cold
Vallejo Temperatures Compared World Wide
Vallejo’s average annual maximum temperature is 21°C. Let’s compare this with some popular tourist destinations:
In Lisbon, Portugal, the average annual temperature is 21°C, offering warm summers and mild, rainy winters.
In contrast, in ReykjavÃk, Iceland, the average annual temperature is significantly lower at 9°C, with mild summers and cold winters.
Osaka, Japan, offers a similar climate to Tokyo, with an average annual temperature of 22°C.
Adelaide, Australia, enjoys warm summers and mild winters, with an average annual temperature of 21°C.
How does the temperature feel?
Humidity is an essential factor in how you experience temperature. When a warm period is accompanied by high humidity, it results in a higher perceived temperature. This is especially true when temperatures exceed 25°C, as it can cause greater discomfort.
In Vallejo, during the coolest month, January, you will experience 80% humidity, which is considered very high. This is accompanied by an average maximum temperature of 15°C. In the warmest month, September, the humidity is 73% combined with an average maximum temperature of 27°C, which creates a high-feel temperature. Explore our detailed page on humidity levels for further details.
How are these Temperatures Measured?
Generally, temperature data depicting climate is usually given over a 30-year average in order to reduce short-term fluctuations and reveal better long-term trends in climate conditions.
This temperature data is taken from land-based thermometers, ocean buoys, ships, and satellites. These measurements are transmitted to weather stations and climate centers around the globe where they are processed, averaged, and analyzed in order to monitor the trends and create climate models.
Temperatures in the Mountains
Although not all regions have mountains, elevated areas exhibit distinct temperature variations.
- Sun Exposure: Sunlit slopes tend to be warmer, while shaded areas remain cooler.
- Altitude Effects: Temperatures drop by approximately 6°C for every 1,000 meters of elevation, creating distinct microclimates.
For more detailed information about Vallejo’s weather, including monthly rainfall, sunshine hours, and humidity levels, visit our Vallejo climate page.
Current temperature in Vallejo (CA)
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