| Date | Mean
  Pressure (hPa) | Air
  Temperature | Mean Relative Humidity (%) | Total Rainfall (mm) | ||
| Maximum (deg. C) | Mean (deg. C) | Minimum (deg. C) | ||||
| September  2018 | ||||||
| 01 | 1009.9 | 27.9 | 26.3 | 25 | 93 | 32 | 
| 02 | 1007.9 | 29.9 | 26.8 | 24.6 | 88 | 9.8 | 
| 03 | 1006.9 | 30.5 | 27.7 | 25.6 | 82 | 0.3 | 
| 04 | 1005.7 | 32 | 29.1 | 27 | 80 | 0 | 
| 05 | 1004.9 | 33.1 | 29.8 | 27.9 | 79 | 0.1 | 
| 06 | 1005.4 | 31.8 | 29.6 | 28.2 | 82 | 0 | 
| 07 | 1006.3 | 31.2 | 29.4 | 28 | 80 | Trace | 
| 08 | 1008.6 | 29.6 | 27.4 | 25.6 | 81 | 24.6 | 
| 09 | 1011.5 | 30.5 | 27.1 | 24.6 | 76 | 16.7 | 
| 10 | 1012.5 | 28.3 | 26.1 | 24.3 | 80 | 0.2 | 
| 11 | 1009.3 | 32.7 | 28.2 | 25.2 | 65 | 0 | 
| 12 | 1007.7 | 28.7 | 27.8 | 26.9 | 78 | Trace | 
| 13 | 1009.4 | 30.3 | 27.7 | 26.3 | 84 | 2.5 | 
| 14 | 1009.2 | 31.7 | 28.8 | 26.7 | 78 | 0 | 
| 15 | 1002.8 | 35.1 | 30.7 | 26.8 | 65 | Trace | 
| 16 | 990.9 | 31.8 | 26.4 | 23.6 | 86 | 167.5 | 
| 17 | 1008.6 | 30.4 | 27.5 | 25.8 | 89 | 12 | 
| 18 | 1013.7 | 31.8 | 28.2 | 26.5 | 85 | 1.2 | 
| 19 | 1012.7 | 31.4 | 28.6 | 26.2 | 77 | 0 | 
| 20 | 1011 | 31.9 | 29 | 27 | 77 | 0 | 
| 21 | 1011.6 | 31.9 | 29.2 | 27.4 | 71 | 0 | 
| 22 | 1013.3 | 33.2 | 29.2 | 27 | 76 | 0 | 
| 23 | 1013.1 | 32.4 | 29 | 27.6 | 78 | Trace | 
| 24 | 1011.1 | 29.6 | 27 | 24.8 | 88 | 72.2 | 
| 25 | 1009.9 | 30.2 | 27 | 24.8 | 80 | 34.5 | 
| 26 | 1009.6 | 28.6 | 26.8 | 25.1 | 81 | 9.7 | 
| 27 | 1009.8 | 30.2 | 27.3 | 26 | 77 | Trace | 
| 28 | 1009.9 | 31.3 | 27.6 | 25.8 | 70 | 0 | 
| 29 | 1008.9 | 31.3 | 27.4 | 24.3 | 60 | 0 | 
| 30 | 1009.9 | 27.9 | 26.3 | 25 | 93 | 32 | 
Source: Hong Kong
Observatory – Hong Kong Observatory