Weather in Semarang in October

A hard month. October asks something of you. Go in knowing what. Daytime highs average 34.7 °C and the afternoon is not negotiable — outdoor plans move to early morning or evening.

October ranks 12 of 12 — near the bottom of Semarang's year. July is the month that works, and the swing between the two is 30 points, which is a different holiday rather than a slightly better one.

Rain on 15 days, 4 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for heat management rather than style: shade, water, and a schedule that gives up on the middle of the day.

What the averages hide

Averages flatten a month, and this one hides a few things: 16 days clear 35 °C, so a serious heatwave is normal rather than notable. Across the twenty years measured, the hottest October day reached 39.7 °C and the coldest night fell to 21.9 °C, and the wettest single day dropped 62 mm — roughly 53% of the month's rain in one day.

October is moderately variable: 0 mm in the driest year against 290 mm in the wettest, around an average of 118 mm. Roughly two Octobers in three land near that average, and the third does something else entirely.

Wind is light at 7.3 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 67%.

How October sits in the year

Temperatures hold steady either side: 35.4 °C in September, 34.7 here, 32.1 in November. Nothing about the timing within the month matters much. Rain is the thing that moves: November brings 8 days more of it, so the earlier half of a flexible trip is the safer half.

Daylight in October

Semarang sits close enough to the equator that daylight barely moves all year — 12.2 hours in October, 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 29.1 °C in October — warm enough that the water offers no relief from the heat. The sea peaks at 29.9 °C in May and bottoms out at 28.5 °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

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

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

October in Semarang versus nearby

If Semarang is one option among several, the nearby comparison is worth making. Jepara is a better bet in October — 4.1 °C cooler, 1 day more rain. Surabaya is a better bet in October — within a degree on temperature, 5 days less rain.

So: October is a compromise. July is 30 points better and is what Semarang 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 Semarang

See all twelve months in Semarang, or where else to go in October.