Ljubljana weather by month
Ljubljana runs from about 0°C in January to 24°C in August, with September the wettest month at 201 mm.
warmest month
August
24°C
coolest month
January
0°C
wettest month
September
201 mm
worst air month
December
47 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 0°C | 142 mm | 176 h | 39 |
| February | 5°C | 82 mm | 159 h | 35 |
| March | 8°C | 128 mm | 230 h | 27 |
| April | 11°C | 80 mm | 279 h | 16 |
| May | 15°C | 177 mm | 312 h | 11 |
| June | 19°C | 109 mm | 341 h | 9 |
| July | 23°C | 54 mm | 409 h | 7 |
| August | 24°C | 36 mm | 388 h | 9 |
| September | 16°C | 201 mm | 260 h | 9 |
| October | 13°C | 174 mm | 166 h | 14 |
| November | 4°C | 69 mm | 158 h | 25 |
| December | 0°C | 52 mm | 148 h | 47 |
About 3,026 hours of sun a year. Roughly 130 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 2026-05-22. Full method, licences and the list of sources we rejected are on the methodology page.