Weather in Surabaya in July

A good month. July is a solid month to be in Surabaya. Highs average 31.2 °C, lows 24.7 °C, and rain falls on 6 days — nothing in the month is working against you.

July ranks 2 of 12 in Surabaya. Only August scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 6 days, so an itinerary with no wet-weather fallback is a reasonable risk. Pack for 31.2 °C days and 24.7 °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: 26 days top 30 °C, making the heat continuous rather than occasional. Across the twenty years measured, the hottest July day reached 33.8 °C and the coldest night fell to 21.9 °C, and the wettest single day dropped 40 mm — roughly 114% of the month's rain in one day.

This is the volatile part. July rainfall has ranged from 0 mm to 138 mm across the twenty years measured — a 138 mm spread around an average of 35 mm. The average is real but almost no individual July looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind is light at 11.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 72%.

How July sits in the year

Temperatures hold steady either side: 30.5 °C in June, 31.2 here, 32.4 in August. Nothing about the timing within the month matters much. Rain has already shifted: 5 days fewer than June had.

Daylight in July

Surabaya sits close enough to the equator that daylight barely moves all year — 11.7 hours in July, against a range of just 0.8 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 28.5 °C in July — warm enough that the water offers no relief from the heat. The sea peaks at 29.8 °C in April and bottoms out at 28.1 °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

Peak season. Expect the highest prices of the year and to be booking well ahead. If the dates are flexible, September is the trade worth considering — 11 points weaker on weather, and materially quieter.

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

July in Surabaya versus nearby

If Surabaya is one option among several, the nearby comparison is worth making. Jepara is close enough to be a coin toss — within a degree on temperature, 2 days more rain. Semarang is close enough to be a coin toss — within a degree on temperature, 1 day more rain.

So: July is effectively as good as it gets here — 3 points behind August, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Surabaya

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