Climate and Weather Characteristics of San Jose, California
San Jose, California, is located at the southern end of San Francisco Bay in Santa Clara County. As the largest city in the county and a major center of Silicon Valley, San Jose combines a large urban area with diverse natural landscapes. The city covers about 178 square miles of land and had an estimated population of 989,814 in 2025, according to the U.S. Census Bureau.
San Jose's geography plays an important role in shaping local weather. The city sits within the Santa Clara Valley, with the Santa Cruz Mountains to the west and south and the Diablo Range to the east.
Northern San Jose reaches the southern end of San Francisco Bay, while parts of the city extend into surrounding foothills. This combination of valley, bay, and mountain terrain creates noticeable differences in weather across the city.
The city's position between coastal and inland environments also affects how strongly marine air influences temperatures. Bay areas and lower elevations tend to experience more moderation, while foothill and inland sections can see greater temperature variation.
San Jose's Mediterranean Climate
San Jose has a Mediterranean-type climate, characterized by warm, very dry summers and cool, relatively rainy winters. Rainfall is strongly seasonal, with most precipitation occurring during the cooler months.
The National Weather Service notes that about 82% of annual precipitation falls between November and March, while rainfall is sparse during much of the late spring and summer.
Summer weather is generally warm and sunny. Mid-summer daytime temperatures commonly reach around 80–85°F, while nighttime temperatures are often in the 55–60°F range.
Winter is considerably cooler but remains relatively mild, with daytime highs generally around 55–60°F and nighttime temperatures near 40°F.
Local Weather Features in San Jose
One distinctive feature of San Jose's weather is the influence of the afternoon sea breeze. During the dry season, winds are often light from the evening through the morning before a northwest breeze develops in the afternoon.
This marine influence can moderate daytime temperatures, particularly when onshore flow is stronger.
San Jose can also experience nighttime low clouds during the warmer months as marine air moves inland from the coast and bay. These clouds may persist into the morning before gradually clearing.
However, when offshore winds replace the usual marine flow, the cooling influence can disappear and temperatures may rise sharply. Under these conditions, temperatures can reach 100°F or higher during the dry season.
Rainfall also varies across the city because of local topography. San Jose typically receives around 14–15 inches of rain annually, while some eastern foothill areas can receive considerably more. This means precipitation patterns are not always uniform across the entire city.
Local Weather Across San Jose
These geographic and climatic differences mean that weather can vary between downtown, the bay flats, valley neighborhoods, and foothill areas.
Areas closer to the bay may experience stronger marine moderation, while higher elevations can see cooler nights and larger temperature swings. During winter, rain becomes more frequent, while summer usually brings long periods of dry weather.
Overall, San Jose's weather is shaped by its Mediterranean climate, valley location, nearby mountains, and connection to the Pacific and San Francisco Bay. These factors create generally mild conditions but can also produce noticeable differences in temperature, wind, and rainfall from one part of the city to another.
Check the weather forecast for San Jose, California to stay updated on current conditions, temperature changes, rainfall, wind, and upcoming weather patterns.
FAQs about San Jose Weather
What is the temperature in San Jose right now?
The current temperature in San Jose is 71°F, with a feels-like temperature of around 80°F.
What is the humidity in San Jose today?
The humidity in San Jose, California is currently 41%, which can affect how comfortable the air feels, especially when temperatures are higher.
Will it rain in San Jose today?
The chance of rain in San Jose, California ranges from 0% to 0%, with the highest probability around 15:00.
What will the weather be like in San Jose this week?
The 7-day forecast for San Jose shows temperatures ranging from 49°F to 71°F, while rain chances may vary between 0% and 0%.
What is the UV Index in San Jose today?
The UV Index in San Jose is currently 7 indicating High UV exposure. Check the latest UV forecast when planning time outdoors.