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Daily News Analysis

Heat Index

22nd July, 2023 Environment

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  • In Rajya sabha, Union minister of Earth sciences, Kiren Rijiju informed that a head index on experimental basis is released by India Meteorological Department (IMD).
  • It will provide general guidance for the warmer regions of India where high temperature is causing discomfort for the people 

Heat Index

  • This index is developed on the lines of the heat index equation used by National Weather Service, National Oceanic and Atmospheric Administration (NOAA), USA.
  • For Bhubaneshwar and Ahmedabad heat index is created under Heat Action Plan which is being done under project mode by National Disaster Management Authority (NDMA).
  • Many local agencies like Indian Institute of Public Health (IIPH) are helping NDMA for this.
  • For entire country the heat index will be issued every day in weather bulletins.


  • It will help people in understanding the impact of humidity on the high temperatures.
  • The information provided by this index could be utilized to identify the heat implications to humans and to understand temperature ranges which are causing discomfort.
  • It will also help in guiding people to take additional care in order to reduce the discomfort.
  • It will provide day's minimum and maximum temperatures and also will inform what the existing temperature feels like.
  • It will utilize air temperature and relative humidity data.
  • However it is experimental and there is a need to change and validate this according to the Indian conditions.

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Heat Index color coding

  • Green - Experimental heat Index less than 35 deg C.
  • Yellow - Experimental heat Index in the range of 36-45 deg C.
  • Orange - Experimental heat Index in the range of 46-55 deg
  • Red - Experimental heat Index greater than 55 deg C.

Must Read Article:

India Meteorological Department (IMD)


Heat Waves





Consider the following statements about recently launched Heat Index in India:

1. This index is released by National Institute of Ocean Technology on an experimental basis.

2. Orange color code refers to a situation where the experimental heat Index is in the range of 36-45 deg C.

Which of the statements given above is/are correct?

A. 1 only

B. 2 only

C. Both 1 and 2

D. Neither 1 nor 2

Answer: (D)