Weather in San Jose in July

Prime time. July is about as good as San Jose gets. Highs average 31.2 °C, lows 13.3 °C, and rain falls on 0 days — nothing in the month is working against you.

July ranks 6 of 12 in San Jose: past the worst of the year but short of May, which is the month to book if the dates are open.

Rain is not a factor worth planning around this month. Pack for 31.2 °C days and 13.3 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 6 days clear 35 °C, so a serious heatwave is normal rather than notable; the day swings 17.8 °C from low to high, which means one bag has to cover both. Across the twenty years measured, the hottest July day reached 46.6 °C and the coldest night fell to 9.1 °C.

July is dependably dry, and that reliability is the point: across the twenty years measured, the wettest July on record still only managed 2 mm, and the driest managed 0 mm. There is no meaningful variability to plan around, which makes this one of the few months anywhere that you can build a fixed outdoor itinerary against without a fallback. The wettest single day in twenty years of Julys brought 1 mm. Rain simply is not the variable that decides this trip — heat, crowds and cost are.

Wind is light at 10.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 62%.

How July sits in the year

Temperatures hold steady either side: 28 °C in June, 31.2 here, 31.6 in August. Nothing about the timing within the month matters much.

Daylight in July

July is at or near the longest days of San Jose's year: 14.5 hours of daylight, losing 0.6 hours across the month. Evenings are the real gain — dinner outdoors still happens in full light.

Sea temperature

The sea sits at about 14.3 °C in July — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 15.4 °C in September and bottoms out at 12.3 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

July in San Jose versus nearby

If San Jose is one option among several, the nearby comparison is worth making. San Francisco is a better bet in July — 8.4 °C cooler, the same number of rain days. Napa is the weaker option in July — 2.7 °C warmer, the same number of rain days.

So: July works, with May the better month by 14 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in San Jose

See all twelve months in San Jose, or where else to go in July.