Climate averages 1991–2020
Surabaya weather
in December.
A hot, very wet month: the 9th warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a hot month in Surabaya: daytime highs average 29.9°C and nights cool to about 25.1°C. By daytime temperature it is the 9th warmest of the 12 months.
Expect about 274 mm of rain on roughly 29 days, which makes December a very wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 32 min on an average December day.
The nearest other city in this atlas is Kebomas (16 km away). In December its highs average 29.6°C, about as warm as Surabaya, with 274 mm of rain.
Among the 200 cities listed in Indonesia, Surabaya ranks joint 12th of 200 for the warmest December highs and joint 41st of 200 for the driest December (rainfall, lowest first). The mean December high of those 200 cities is 28.4°C; Surabaya is 1.4°C warmer than that mean.
From December to January, average highs fall by 0.6°C to 29.3°C, and monthly rainfall rises from 274 mm to 280 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Surabaya climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.3°C24.8°C | 24.8°C | 280 | 29.4 | 12.512 h |
| February | 29.3°C24.8°C | 24.8°C | 262 | 27.3 | 12.312 h |
| March | 29.8°C25.0°C | 25.0°C | 268 | 28.9 | 12.112 h |
| April | 30.1°C25.1°C | 25.1°C | 186 | 23.9 | 11.912 h |
| May | 30.5°C25.1°C | 25.1°C | 86 | 14.5 | 11.812 h |
| June | 30.4°C24.5°C | 24.5°C | 49 | 9.0 | 11.712 h |
| July | 30.6°C23.9°C | 23.9°C | 22 | 4.5 | 11.712 h |
| August | 31.5°C23.9°C | 23.9°C | 6.4 | 1.5 | 11.912 h |
| September | 32.9°C24.5°C | 24.5°C | 20 | 3.3 | 12.112 h |
| October | 32.9°C25.3°C | 25.3°C | 73 | 12.5 | 12.312 h |
| November | 31.3°C25.5°C | 25.5°C | 179 | 24.1 | 12.412 h |
| December, selected | 29.9°C25.1°C | 25.1°C | 274 | 28.7 | 12.513 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- Kebomas in DecemberIndonesia · 16 kmHigh 29.6°C · Low 24.4°C · 274 mm rain
- Sidoarjo in DecemberIndonesia · 22 kmHigh 30.2°C · Low 24.0°C · 253 mm rain
- Bangkalan in DecemberIndonesia · 23 kmHigh 29.3°C · Low 25.4°C · 280 mm rain
- Bangil in DecemberIndonesia · 40 kmHigh 29.6°C · Low 23.1°C · 253 mm rain
- Mojokerto in DecemberIndonesia · 42 kmHigh 30.4°C · Low 23.2°C · 447 mm rain
- Pasuruan in DecemberIndonesia · 47 kmHigh 29.1°C · Low 23.3°C · 321 mm rain
- Lawang in DecemberIndonesia · 65 kmHigh 27.9°C · Low 21.6°C · 420 mm rain
- Jombang in DecemberIndonesia · 66 kmHigh 30.0°C · Low 23.2°C · 266 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Surabaya) is explained once on the Surabaya year overview and on the Sources, method and limits page.
Kebomas lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.