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Bulletin updated at 00:15 HKT
28/ May /2017

Yesterday's Weather and Radiation Level

Hong Kong Observatory:
Maximum Air Temperature: 30.4 C
Minimum Air Temperature: 24.0 C
Grass Minimum Temperature: 23.3 C
Relative Humidity: 40 - 83 percent
Rainfall: Trace

Total Rainfall since 1st January: 533.8 mm
Against an average of 581.8 mm

Other Stations
King's Park
23.3 C
29.4 C
Wong Chuk Hang
21.6 C
29.6 C
Ta Kwu Ling
20.6 C
31.0 C
Lau Fau Shan
22.3 C
31.6 C
Tai Po
22.0 C
28.9 C
Sha Tin
21.8 C
30.4 C
Tuen Mun
22.4 C
31.1 C
Tseung Kwan O
21.2 C
30.0 C
Sai Kung
22.5 C
29.0 C
Cheung Chau
22.8 C
28.5 C
Chek Lap Kok
23.6 C
31.7 C
Tsing Yi
22.3 C
31.4 C
Shek Kong
21.5 C
31.4 C
Tsuen Wan Ho Koon
21.0 C
30.2 C
Tsuen Wan Shing Mun Valley
21.3 C
29.9 C
Hong Kong Park
23.1 C
30.0 C
Shau Kei Wan
22.9 C
28.6 C
Kowloon City
23.3 C
30.7 C
Happy Valley
22.6 C
31.1 C
Wong Tai Sin
22.5 C
30.1 C
22.9 C
29.4 C
Kwun Tong
23.4 C
29.3 C
Sham Shui Po
23.5 C
31.1 C

Duration of Sunshine (King's Park): 7.5 H
The mean UV Index recorded at King's Park yesterday was 5,
the UV intensity was Moderate
The maximum UV Index for yesterday was 10.
Yesterday's (27 May) 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.