Semarang weather by month
Semarang runs from about 27°C in January to 30°C in May, with December the wettest month at 303 mm.
warmest month
May
30°C
coolest month
January
27°C
wettest month
December
303 mm
worst air month
October
36 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 27°C | 274 mm | 275 h | 14 |
| February | 27°C | 248 mm | 272 h | 18 |
| March | 27°C | 217 mm | 291 h | 22 |
| April | 28°C | 195 mm | 294 h | 31 |
| May | 30°C | 29 mm | 336 h | 33 |
| June | 28°C | 70 mm | 317 h | 34 |
| July | 28°C | 36 mm | 339 h | 31 |
| August | 28°C | 14 mm | 346 h | 32 |
| September | 29°C | 79 mm | 326 h | 35 |
| October | 29°C | 59 mm | 348 h | 36 |
| November | 28°C | 287 mm | 276 h | 29 |
| December | 27°C | 303 mm | 226 h | 22 |
About 3,646 hours of sun a year. Roughly 182 rainy days a year.
These are long-run climate normals, not a forecast. A given year can sit well outside them. PM2.5 is a global model: near the coast it counts sea salt as fine particulate and reads high against ground stations, sometimes by a factor of two. Use the shape of the year, not the absolute number.
where these numbers come from
- · Temperature, rainfall and sunshine: ECMWF ERA5 reanalysis climate normals via Open-Meteo (CC BY 4.0), fetched once and stored.
- · PM2.5: Copernicus CAMS reanalysis, monthly means. Modelled, not station readings; near coasts CAMS counts sea salt as PM2.5 and reads high.
Last reviewed 2026-05-24. Full method, licences and the list of sources we rejected are on the methodology page.