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Bulletin updated at 00:15 HKT
30/ Mar /2017

Yesterday's Weather and Radiation Level

Hong Kong Observatory:
Maximum Air Temperature: 23.7 C
Minimum Air Temperature: 20.4 C
Grass Minimum Temperature: 19.6 C
Relative Humidity: 74 - 90 percent
Rainfall: 0.3 mm

Total Rainfall since 1st January: 53.8 mm
Against an average of 154.8 mm

Other Stations
King's Park
19.8 C
24.0 C
Wong Chuk Hang
20.3 C
24.6 C
Ta Kwu Ling
19.7 C
25.7 C
Lau Fau Shan
19.1 C
29.2 C
Tai Po
19.9 C
23.0 C
Sha Tin
19.9 C
23.2 C
Tuen Mun
20.1 C
25.5 C
Tseung Kwan O
19.4 C
22.9 C
Sai Kung
19.8 C
22.4 C
Cheung Chau
19.5 C
24.2 C
Chek Lap Kok
21.0 C
27.4 C
Tsing Yi
20.6 C
25.6 C
Shek Kong
19.9 C
25.9 C
Tsuen Wan Ho Koon
19.6 C
25.5 C
Tsuen Wan Shing Mun Valley
20.7 C
25.2 C
Hong Kong Park
20.0 C
24.0 C
Shau Kei Wan
19.2 C
21.7 C
Kowloon City
19.9 C
25.4 C
Happy Valley
20.4 C
24.9 C
Wong Tai Sin
20.3 C
25.1 C
Kwun Tong
19.7 C
23.7 C
Sham Shui Po
20.5 C
25.4 C

Duration of Sunshine (King's Park): 0.7 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 6.
Sea surface temperature (Waglan Island):19.2 C

Yesterday's (29 Mar) average ambient gamma radiation dose rate taken outdoors in Hong Kong ranged from 0.08 to 0.14 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 :

Yesterday's average (microsievert/hour)
King's Park
Ping Chau
Tap Mun
Kat O
Yuen Ng Fan
Tai Mei Tuk
Sha Tau Kok
Kwun Tong
Sai Wan Ho
Tsim Bei Tsui

  1. From readings taken at various locations in Hong Kong during the period 1987-2016, the background ambient gamma radiation levels may vary between 0.06 and 0.30 microsievert per hour.
  2. The extent of health effects to a person as a result of exposure to radiation is expressed by a physical quantity called equivalent dose, in unit of sievert. Protective action may be required if there is an increase in the ambient gamma dose rate above background such that the total additional dose is expected to exceed 5000 microsieverts in a relatively short period of time. For example, a dose of 5000 microsieverts may be reached when the ambient gamma dose rate is 1000 microsieverts per hour (several thousand times above background) and lasts for 5 hours.
  3. The readings of ambient gamma radiation level from instrument are expressed in unit of gray, which is numerically equal to the gamma dose expressed in sievert.