Why in the news?

• Recently, The Konkan region, including Mumbai, has been experiencing sweltering heat, with the maximum temperatures touching the 40 degrees mark.

What is a heatwave?

• A region or locality is considered to be under the influence of heatwave if the maximum temperature reaches or exceeds 40 degrees Celsius in the plains, or 30 degrees Celsius in hilly regions.
• Over the coastal regions, the threshold for the maximum temperature is 37 degrees.
• When the maximum temperature departure ranges between 4.5 and 6 degrees, the India Meteorological Department (IMD) declares a heatwave. For instance, if the normal temperature of a locality should be 40 degrees, and the actual recorded temperature is 45 degrees, the locality is under heatwave.
• Likewise, severe heatwave is declared when the recorded maximum temperature of a plocality departure from normal is over 6.4 degrees.
• This apart, if the locality records over 45 degrees and 47 degrees on any given day, then the IMD declares heatwave and severe heatwave, respectively.
• In India, heat waves occur from March to June, occasionally in July. The peak heatwave events have been reported in the month of May.
• As per the IMD, the most heatwave prone states are Punjab, Haryana, Delhi, Uttar Pradesh, Bihar, Jharkhand, West Bengal, Odisha, Madhya Pradesh, Rajasthan, Gujarat, Vidarbha, and parts of Karnataka, Andhra Pradesh, Telangana, and occasionally over Tamil Nadu and Kerala.

So, why is Konkan experiencing heatwave conditions?

• The ongoing heatwave in Konkan, including Mumbai, is because it is under the direct influence of the prevailing heatwave in the adjacent Saurashtra-Kutch regions of Gujarat.
• The hot and dry winds from northwest India are reaching parts of Konkan.

Reference:

1. https://indianexpress.com/article/explained/konkan-mumbai-heatwave-explained-7820628/