WEATHER · CLIMATE NORMALS · 1991–2020
Thessaloniki Climate — Averages by Month
What the weather in Thessaloniki, GRaverages 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 | 4.2 °C · coldest | 53.7 mm |
| February | 6.3 °C | 51.4 mm |
| March | 9.6 °C | 65.5 mm |
| April | 13.9 °C | 60.6 mm |
| May | 18.9 °C | 71.9 mm |
| June | 23.5 °C | 53.6 mm |
| July | 25.8 °C · warmest | 46.9 mm |
| August | 25.6 °C | 46.0 mm |
| September | 21.0 °C | 53.5 mm |
| October | 15.8 °C | 60.6 mm |
| November | 10.4 °C | 62.7 mm |
| December | 5.4 °C | 72.2 mm · wettest |
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 Thessaloniki — centred at 40.75°N, 23.00°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.