Yesterday's Weather and Radiation Level

Bulletin issued at 00:15 HKT 19/Jan/2025

HKO Readings & Radiation level

Yesterday's Weather and Radiation Level:
------------------------------------------------------

Hong Kong Observatory
Maximum Air Temperature                     19.5 C
Minimum Air Temperature                     14.2 C
Grass Minimum Temperature                   11.2 C
Relative Humidity                        44 - 73 Percent
Rainfall                                       0 mm 
Total rainfall since 1st January              Trace
Against an average of                       18.6 mm

Other Stations                Min                  Max
King's Park                  12.7 C               20.3 C
Wong Chuk Hang               12.5 C               20.1 C
Ta Kwu Ling                   6.9 C               22.7 C
Lau Fau Shan                 11.2 C               20.8 C
Tai Po                       10.6 C               20.1 C
Sha Tin                      10.9 C               20.8 C
Tuen Mun                     11.7 C               21.0 C
Tseung Kwan O                12.0 C               20.4 C
Sai Kung                     11.6 C               18.8 C
Cheung Chau                  12.1 C               21.3 C
Chek Lap Kok                 13.1 C               19.8 C
Tsing Yi                     12.4 C               20.7 C
Shek Kong                     9.5 C               22.3 C
Tsuen Wan Ho Koon             9.9 C               19.9 C
Tsuen Wan Shing Mun Valley   10.6 C               21.9 C
Hong Kong Park               13.2 C               19.6 C
Shau Kei Wan                 12.5 C               18.0 C
Kowloon City                 12.3 C               21.6 C
Happy Valley                 13.5 C               21.1 C
Wong Tai Sin                 12.6 C               21.0 C
Stanley                      13.4 C               18.1 C
Kwun Tong                    12.8 C               20.0 C
Sham Shui Po                 12.7 C               21.1 C
Kai Tak Runway Park          14.1 C               18.7 C
Yuen Long Park                9.6 C               23.1 C
Tai Mei Tuk                  12.1 C               21.8 C

Duration of sunshine (King's Park):              9.9 H
The mean UV index recorded at King's Park yesterday was 2,
the UV intensity was LOW.
The maximum UV index for yesterday was 5.
Sea Surface Temperature (Waglan Island):        17.1 C
Yesterday's (18 Jan 2025) average ambient gamma radiation
dose rate taken outdoors in Hong Kong ranged from 0.09 to
0.15 microsievert per hour.  These are within the normal
range of fluctuation of the background radiation level in
Hong Kong (See Note). The average dose rates measured at the
radiation monitoring stations over various parts of the
territory were as follows :

Station                     Yesterday's average
                            (microsievert/hour)
Ping Chau                           0.09
Tap Mun                             0.09
Kat O                               0.10
Yuen Ng Fan                         0.12
Tai Mei Tuk                         0.12
Sha Tau Kok                         0.10
Kwun Tong                           0.13
Sai Wan Ho                          0.09
King's Park                         0.15
Tsim Bei Tsui                       0.13
Cape D'Aguilar                      0.12
Chek Lap Kok                        0.15   


Note
1.     From readings taken at various locations in Hong Kong in the
       past, the hourly mean ambient gamma radiation dose rate may
       vary between 0.06 and 0.3 microsievert per hour. (1
       microsievert = 0.000001 sievert = 0.001 millisievert)

2.     Temporal variations are generally caused by changes in
       meteorological conditions such as rainfall, wind and
       barometric pressure.

3.     Spatial variations are generally caused by differences in
       the radioactive content of local rock and soil.

4.     The data displayed is provisional. Only limited data
       validation has been carried out.

5.     The range of relative humidity in the daily weather summary
       originates from the observer's reports of Hourly
       Readings of the day. This follows the long-term practice of
       collecting climatological data of the Hong Kong Observatory
       for over a century. It may differ from the relative humidity
       range derived from the 1-minute reports of the automatic
       weather station.