Weather in Surabaya in June

A good month. June works. It is not the peak, but nothing about it fights you. Highs average 30.5 °C, lows 25.3 °C, and rain falls on 11 days — nothing in the month is working against you.

June ranks 3 of 12 in Surabaya. Only August scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain on 11 days, 2 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 30.5 °C days and 25.3 °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: 20 days top 30 °C, making the heat continuous rather than occasional; the day barely swings — 5.2 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest June day reached 32.9 °C and the coldest night fell to 22.9 °C, and the wettest single day dropped 33 mm — roughly 45% of the month's rain in one day.

This is the volatile part. June rainfall has ranged from 3 mm to 289 mm across the twenty years measured — a 286 mm spread around an average of 74 mm. The average is real but almost no individual June looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind is light at 10.4 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 77%, high enough to notice on the warm days without dominating them.

How June sits in the year

Temperatures hold steady either side: 30.2 °C in May, 30.5 here, 31.2 in July. Nothing about the timing within the month matters much. Rain is the thing that moves: July brings 5 days less of it, so pushing the dates later buys drier weather.

Daylight in June

Surabaya sits close enough to the equator that daylight barely moves all year — 11.7 hours in June, 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 29.3 °C in June — 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

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.

June 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, 3 days more rain. Semarang is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: June works, with August the better month by 9 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Surabaya

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