Question 1

When is the sunniest time of year in San José?

Accepted Answer

Summer is the sunniest time of year in San José, with the meteorological summer months of June to August 2025 delivering more sunshine than any other season. The city recorded about 1,229 hours of sunshine across these three months, averaging roughly 410 hours per month, or close to 13.4 hours of sun per day.

July 2025 was the single sunniest month in San José, logging 429 hours of sunshine — nearly 13.8 hours per day. Summer was also remarkably dry, with just 0.2 mm (0.01 in) of total rainfall over the entire June–August period, alongside warm average temperatures of around 19°C (66°F).

For comparison, the darkest stretch came in early winter: December 2025 saw only 174 hours of sunshine (about 5.6 hours per day). Spring (March–May) and autumn (September–November) fell in between, recording roughly 905 and 759 hours respectively. Across all of 2025, San José accumulated about 3,502 sunshine hours.

If you're planning sun-dependent activities in San José — outdoor dining, hiking the nearby foothills, or sightseeing — the late spring through summer window offers the most reliable conditions. June through August combines near-daily sunshine with virtually no rain, making it the standout period for soaking up San José's famously bright Mediterranean climate.

Question 2

Which season is the wettest in San José?

Accepted Answer

Autumn (September to November) was the wettest season in San José in 2025, delivering about 141.9 mm (5.59 in) of rain — more than any other meteorological season that year.

San José has a classic Mediterranean climate, with rainfall concentrated in the cooler half of the year and almost none in summer. During autumn 2025, November alone brought 78.6 mm (3.09 in), making it the standout month of the season. Meteorological winter within 2025 (January and February only) was the next wettest period at 104.5 mm (4.11 in), and February was the single rainiest month of the entire year with 94.4 mm (3.72 in).

The contrast with summer is striking. The summer months (June to August) recorded just 0.2 mm (0.01 in) of total precipitation across all of San José, with June and July seeing essentially no rain at all. Spring (March to May) was transitional at 88.5 mm (3.48 in), tapering off quickly toward the dry season.

For visitors and residents, this means San José's rainy stretch runs from autumn into late winter, so anyone planning outdoor activities should expect the most reliably dry conditions between June and September. Across all of 2025, San José received 389.4 mm (15.33 in) of precipitation, confirming its reputation as a relatively dry, sunshine-favored city where wet weather is heavily seasonal rather than year-round.

Question 3

What was the hottest day in San José in 2025?

Accepted Answer

The hottest day in San José in 2025 was September 23, when the temperature peaked at 38.0°C (100.4°F). This late-summer scorcher topped every other day of the year and highlights how San José's most intense heat tends to arrive in late summer and early autumn rather than mid-summer.

The heat was clustered in the warmest part of the year. Other notably hot days in 2025 included August 31 at 37.0°C (98.6°F) and August 8 at 36.4°C (97.5°F). Across the full year, San José recorded:

- **7 days** reaching 35°C (95°F) or hotter
- **53 days** climbing to at least 30°C (86°F)
- An annual high-to-low swing from 38.0°C (100.4°F) down to a chilly -0.5°C (31.1°F) on February 10

Even on the record-hot September 23, the night cooled to 13.6°C (56.5°F), giving a daily mean of 24.5°C (76.1°F). This wide day-to-night spread is typical of San José's dry climate and means heat rarely lingers overnight.

For visitors and residents, these numbers show that the early-autumn weeks can bring San José's most extreme heat, so it's wise to plan outdoor activities for the morning and stay hydrated when temperatures push past 35°C (95°F).

Question 4

What is the annual temperature range in San José?

Accepted Answer

San José has a mild, narrow temperature range, with average monthly temperatures shifting only about 10.7°C (19.3°F) between the coldest and warmest months of 2025.

Across the full 2025 calendar year, the city's coldest month was January, averaging 9.8°C (49.6°F), while the warmest was September at 20.5°C (68.9°F). The annual mean temperature settled at a comfortable 15.2°C (59.4°F), reflecting San José's classic Mediterranean climate. Typical monthly high readings averaged 31.1°C (88.0°F) and monthly lows averaged 4.9°C (40.9°F).

When looking at absolute extremes, the gap widens considerably. The lowest temperature recorded in San José in 2025 dipped to −0.5°C (31.1°F) in February, while the hottest reached 38.0°C (100.4°F) during a September heat spike. That puts the full 2025 temperature range at roughly 38.5°C (69.3°F) from the coldest night to the hottest afternoon.

For visitors and residents, these conditions make San José pleasant year-round, rarely too cold and only occasionally very hot. The modest swing in average temperatures means you can plan outdoor activities in nearly any month, though packing a light layer for cool mornings and evenings is wise, since daily lows can fall close to freezing in winter even when afternoons feel mild.

Question 5

What is the weather like in San José in July?

Accepted Answer

July is one of the warmest and driest months in San José, delivering reliably sunny skies, hot afternoons, and cool, comfortable nights. In July 2025, the city recorded no measurable rainfall at all (0 mm / 0 in), making it an ideal month for outdoor plans.

Daytime highs in San José averaged 28.2°C (82.8°F), while overnight lows dipped to an average of 10.8°C (51.4°F), giving the month a mean temperature of 18.7°C (65.6°F). That wide day-to-night swing of roughly 17.5°C (31°F) is typical of San José's inland valley climate and means warm days are often followed by pleasantly cool evenings.

The month was also exceptionally sunny, with about 13.8 hours of sunshine per day and 429 total sunshine hours across July 2025. Humidity stayed moderate at an average of 68.7%, and winds were light at roughly 9.2 km/h (5.7 mph).

Heat peaked on July 11, 2025, when the temperature hit 34.7°C (94.5°F), part of a stretch that saw 9 days reach 30°C (86°F) or higher.

For visitors and residents, July in San José means dependable dry, sunny weather perfect for hiking, sightseeing, or dining outdoors. Just plan strenuous activity for the morning or late afternoon on the hottest days, and bring a light layer for the noticeably cooler evenings.

San Jose

California

Wind

Weather Map

FAQ

When is the sunniest time of year in San José?

Which season is the wettest in San José?

What was the hottest day in San José in 2025?

What is the annual temperature range in San José?

What is the weather like in San José in July?