WEATHER · CLIMATE NORMALS · 1991–2020
Hong Kong Climate — Averages by Month
What the weather in Hong Kong, HKaverages 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 | 16.3 °C · coldest | 35.0 mm |
| February | 17.4 °C | 52.1 mm |
| March | 19.7 °C | 79.5 mm |
| April | 22.8 °C | 126.0 mm |
| May | 25.9 °C | 218.8 mm |
| June | 27.7 °C | 320.5 mm · wettest |
| July | 28.3 °C · warmest | 260.1 mm |
| August | 28.2 °C | 316.7 mm |
| September | 27.5 °C | 220.4 mm |
| October | 25.2 °C | 79.0 mm |
| November | 21.7 °C | 43.1 mm |
| December | 17.7 °C | 37.2 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 Hong Kong — centred at 22.25°N, 114.25°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.