Weather in San Jose in March

A good month. March works. It is not the peak, but nothing about it fights you. Highs average 18.1 °C, lows 7.1 °C, and rain falls on 9 days — nothing in the month is working against you.

March ranks 9 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 on 9 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

Averages flatten a month, and this one hides a few things: it never really gets hot: not one day in an average March reaches 30 °C. Across the twenty years measured, the hottest March day reached 29.9 °C and the coldest night fell to 0 °C, and the wettest single day dropped 48 mm — roughly 62% of the month's rain in one day.

March is moderately variable: 6 mm in the driest year against 175 mm in the wettest, around an average of 77 mm. Roughly two Marchs in three land near that average, and the third does something else entirely.

Wind is light at 6.7 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 82%, high enough to notice on the warm days without dominating them.

How March sits in the year

The month is on the way up: 1.8 °C warmer than February, and April adds another 1.9 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in March

11.9 hours of daylight, gaining 1.2 hours across the month. That is between San Jose's extremes of 14.7 and 9.6 hours, so days are long enough not to constrain the plan.

Sea temperature

The sea sits at about 12.6 °C in March — too cold to swim without a wetsuit. 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

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

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

March in San Jose versus nearby

If San Jose is one option among several, the nearby comparison is worth making. San Francisco is close enough to be a coin toss — within a degree on temperature, 1 day more rain. Napa is close enough to be a coin toss — within a degree on temperature, 1 day more rain.

So: March is a compromise. May is 20 points better and is what San Jose is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in San Jose

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