WEATHER · CLIMATE NORMALS · 1991–2020
Ulaanbaatar Climate — Averages by Month
What the weather in Ulaanbaatar, MNaverages across a standard 30-year period. Each month's figure is the 1991–2020 mean temperature and total rainfall from the ERA5 reanalysis — the long-run normal a place settles around, not a forecast for any particular day.
Month-by-month normals
| Month | Avg temperature | Avg rainfall |
|---|---|---|
| January | -22.9 °C · coldest | 3.7 mm |
| February | -18.0 °C | 5.7 mm |
| March | -8.3 °C | 10.6 mm |
| April | 1.4 °C | 20.3 mm |
| May | 8.4 °C | 38.2 mm |
| June | 14.4 °C | 59.4 mm |
| July | 17.0 °C · warmest | 72.0 mm · wettest |
| August | 14.6 °C | 71.7 mm |
| September | 7.8 °C | 42.8 mm |
| October | -1.2 °C | 17.9 mm |
| November | -12.5 °C | 9.4 mm |
| December | -20.6 °C | 5.0 mm |
How to read these numbers
These are reanalysis normals, not readings from a single weather station. They come from the ERA5 0.25° (~25 km) global reanalysis grid, sampled at the grid cell nearest Ulaanbaatar — centred at 48.00°N, 107.00°E. A reanalysis blends observations with a physics model onto an even grid, so a coastal or mountain city's cell can read a little cooler, warmer, wetter or drier than the city centre itself. The month-to-month shape — when it's hot, when it rains — is what these normals capture best.
“Normal” means the 1991–2020 average, the current World Meteorological Organization standard period. A normal is what a place tends toward over decades — any single day, month or year can and will depart from it.