IMD has launched Heat Index

Source: The post is based on the article “IMD has launched Heat Index”  published in PIB on 20th July 2023.

What is the News?

India Meteorological Department (IMD) has launched the Heat Index on an experimental basis. 

What is the Heat Index?

Source: TOI

Heat Index is also known as the apparent temperature. It is the temperature humans feel when relative humidity combines with the air temperature.

For instance, you may experience unusually high levels of heat despite the official temperature forecast indicating a ‘normal’ range. Say, if the absolute humidity of an area is high, you may feel hot, even though the temperature may not necessarily be that high.

Similarly, say there is a wind blowing; you will automatically feel colder, even if the temperature may not be so low.

How will the Heat Index be calculated by IMD?

At present, heat index is derived using the heat index equation similar to what is used by National Weather Service, National Oceanic and Atmospheric Administration (NOAA), USA.

What are the colour codes used for Heat Index?

The colour codes used for Experimental Heat Index are as follows: 1) Green: Experimental heat Index less than 35 deg C 2) Yellow: Experimental heat Index in the range 36-45 deg C 3) Orange: Experimental heat Index in the range 46-55 deg C and 4) Red: Experimental heat Index greater than 55 deg C.