Bulletin issued at 00:15 HKT 18/May/2025
HKO Readings & Radiation level Yesterday's Weather and Radiation Level: ------------------------------------------------------ Hong Kong Observatory Maximum Air Temperature 32.8 C Minimum Air Temperature 26.7 C Grass Minimum Temperature 25.4 C Relative Humidity 60 - 88 Percent Rainfall 0 mm Total rainfall since 1st January 142 mm Against an average of 437.9 mm Other Stations Min Max King's Park 25.7 C 32.0 C Wong Chuk Hang 24.8 C 30.9 C Ta Kwu Ling 24.4 C 33.0 C Lau Fau Shan 25.3 C 31.8 C Tai Po 25.5 C 32.0 C Sha Tin 24.9 C 32.8 C Tuen Mun 26.1 C 33.0 C Tseung Kwan O 24.8 C 31.0 C Sai Kung 25.9 C 31.4 C Cheung Chau 25.1 C 32.2 C Chek Lap Kok 26.7 C 32.3 C Tsing Yi 25.3 C 31.0 C Shek Kong 24.7 C 33.9 C Tsuen Wan Ho Koon 24.6 C 31.1 C Tsuen Wan Shing Mun Valley 25.4 C 32.0 C Hong Kong Park 25.8 C 30.9 C Shau Kei Wan 25.1 C 31.3 C Kowloon City 25.4 C 33.1 C Happy Valley 25.8 C 32.2 C Wong Tai Sin 25.7 C 33.0 C Stanley 25.3 C 32.1 C Kwun Tong 25.6 C 32.8 C Sham Shui Po 26.1 C 32.5 C Kai Tak Runway Park 26.2 C 32.0 C Yuen Long Park 25.7 C 32.5 C Tai Mei Tuk 25.5 C 32.3 C Duration of sunshine (King's Park):5.7 H The mean UV index recorded at King's Park yesterday was 4the UV intensity was MODERATE The maximum UV index for yesterday was 10. Sea Surface Temperature (Waglan Island): 25.8 C Yesterday's (17 May 2025) average ambient gamma radiation dose rate taken outdoors in Hong Kong ranged from 0.08 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 0.08 Tap Mun 0.08 Kat O 0.10 Yuen Ng Fan 0.11 Tai Mei Tuk 0.12 Sha Tau Kok 0.10 Kwun Tong 0.12 Sai Wan Ho 0.08 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.