Ulaanbaatar weather by month
Ulaanbaatar runs from about -19°C in February to 20°C in July, with August the wettest month at 156 mm.
warmest month
July
20°C
coolest month
February
-19°C
wettest month
August
156 mm
worst air month
December
66 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -18°C | 5 mm | 243 h | 64 |
| February | -19°C | 5 mm | 268 h | 42 |
| March | -6°C | 12 mm | 326 h | 25 |
| April | 4°C | 31 mm | 334 h | 12 |
| May | 12°C | 30 mm | 365 h | 10 |
| June | 16°C | 103 mm | 360 h | 10 |
| July | 20°C | 62 mm | 359 h | 12 |
| August | 17°C | 156 mm | 329 h | 10 |
| September | 10°C | 22 mm | 283 h | 13 |
| October | 1°C | 20 mm | 256 h | 25 |
| November | -5°C | 9 mm | 231 h | 33 |
| December | -18°C | 4 mm | 226 h | 66 |
About 3,580 hours of sun a year. Roughly 46 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 2026-05-27. Full method, licences and the list of sources we rejected are on the methodology page.