2023 Cold Wave Conditions in India

Many parts of India are currently experiencing cold wave conditions around 7 -8 January 2023. Severe cold wave with dense fog observed in the states like Punjab, Haryana, Chandigarh, Delhi, and Uttar Pradesh. The IMD had issued a red warning (meaning 'take action') over many regions in northwest and north India.

Figure: Observed (top panel) maximum temperature, minimum temperature, and mean temperature and the anomaly (bottom panel) of over India during 7 - 8 January 2023 *Based on Realtime Data [Source: IMD]

Figure: Observed minimum temperature anomaly of over India during 5 - 12 January 2023 *Based on Realtime Data [Source: IMD]

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The criteria adopted by IMD to define Cold Wave is given below: 

(A) Cold Wave

Cold Wave conditions for plains or hilly regions

Cold Wave is considered when the minimum temperature of a station is 10 C or less for plains and 0°C or less for Hilly regions. 

       (i) Based on Departure 

           Cold Wave: Negative Departure from normal is 4.5°C to 6.4°C 

           Severe Cold Wave: Negative Departure from normal is more than 6.4°C 

       (ii)   Based on Actual Minimum Temperature (For plain stations only) 

          Cold Wave: When minimum temperature is ≤ 04°C 

          Severe Cold Wave: When minimum temperature is ≤ 02°C 

Cold Wave conditions for coastal stations 

When minimum temperature departure is -4.5°C or less over a station, “Cold Wave” may be described if the minimum temperature is 15°C or less. 

(B) Cold Day:

It should be considered when minimum temperature is 10°C or less for plains and 0°C or less for hilly

regions.

Cold day: Maximum Temperature Departure is -4.5°C to -6.4°C

Severe Cold day: Maximum Temperature Departure is < -6.4°C

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India’s ‘core cold wave zone’ covers Punjab, Himachal Pradesh, Uttarakhand, Delhi, Haryana, Rajasthan, Uttar Pradesh, Gujarat, Madhya Pradesh, Chhattisgarh, Bihar, Jharkhand, West Bengal, Odisha and Telangana.

The maps below from the India Meteorological Department (IMD) show the district-wise cold wave vulnerability index and the district-wise number of cold wave days as per the data for the period 1969–2019.

Figure: Cold wave normalised vulnerability index (Annual). [Source: IMD]

Figure: Number of Cold Wave days (Annual) during the period 1969-2019. [Source: IMD]

A guide, "Surviving Cold Wave" from the National Disaster Management Authority (NDMA) given here. [Source: NDMA]

The IMD follows four categories (red, orange, yellow, and green) to describe weather conditions on India map.

GREEN - No Warning

YELLOW - To Monitor

Orange -Stay Alert

RED - Take Action

References and Acknowledgements

India Meteorological Department (IMD)

National Disaster Management Authority (NDMA)