Very Hot Weather Warning

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Very Hot Weather Warning

This warning was newly introduced on 23 March 2000. This warning aims at enhancing the public's awareness of the impacts of very hot conditions and alerting the public to take precautions against heat-stroke during very hot weather.

Hong Kong experiences hot season. A close watch on the local temperature changes is maintained. Whenever Hong Kong is threatened by very hot weather, Very Hot Weather Warning will be issued to alert members of the public to the risk of heatstroke and sunburn due to very hot weather.

The issuance of the Hot Weather Warning depends on many factors. When the temperature is above 30 degrees Celsius in the urban areas in Hong Kong under certain humidity, wind direction and wind speed, the warning will be issued. In fact, the warning should be issued when the urban temperature rises to or above 34 degrees Celsius.

Once issued, the warning is broadcast over radio and television. If very hot weather persists, the special announcements will be repeated while the warning is in force, to remind the public to take necessary actions.

Points to Note:

  • When engaged in outdoor work or activities, drink plenty of water and avoid over exertion. If not feeling well, take a rest in the shade or cooler place as soon as possible.
  • Avoid prolonged exposure under sunlight.
  • Loose clothing, suitable hats and UV-absorbing sunglasses can reduce the chance of sunburn by solar ultraviolet radiation.
  • Swimmers and those taking part in outdoor activities should use a sunscreen lotion of SPF 15 or above, and should re-apply it frequently.
  • If there is no need to go out, stay indoors.
  • If you know of elderly or persons with chronic medical conditions staying alone, please call or visit them occasionally to check if they need any assistance.
  • Relevant government departments, such as the Social Welfare Department and the Home Affairs Department would consider the need to take actions, such as the opening of temporary shelters, during the warning in effect.
  • It is important that members of the public take note of the warning and steps to protect themselves and their family against very hot weather.
  • The public should listen to radio and television broadcasts for latest weather information.

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