The temperatures in Mumbai have seen a dramatic rise in recent days with maximum temperatures touching the 40-degree mark.
Mumbai recorded its hottest day of the year so far on Monday when the daytime temperature touched 39.6 degrees Celsius. The Met Department has predicted more hot weather, and the way things stand, the city could end up breaking its hottest March day record of 41.7 degrees Celsius, recorded back in 1956.
When is a region under the influence of a heatwave?
If the maximum temperature of a region reaches or exceeds 40 degrees Celsius in the plains or 30 degrees Celsius in hilly regions, it is said to be under the influence of a heatwave.
Similarly, a severe heatwave is when the recorded maximum temperature of a region is over 6.4 degrees above normal.
What explains the heat wave in March this year?
The month of March is when the region extending from Maharashtra to Odisha is a heat zone.
In its March to May seasonal forecast issued on March 1, the IMD had already predicted that it was expecting above normal maximum temperatures most likely over many parts of western and central India and hence a heat wave can be expected extending from south Gujarat to Maharashtra to Odisha.
On the reasons for the heat wave, IMD Director General, Mrutyunjay Mohapatra told IANS: "The higher than normal temperatures are because of the wind flow pattern in these areas. The lower level winds in these areas are from south towards north and that brings hotter air from land (as against when north to south winds bring colder air).
The winds are southeasterly over southern peninsular area, mainly Karnataka, Telangana with some feeble circulation which is favouring the advent of heat from south to north Tamil Nadu, Telangana, Karnataka and up to Vidarbha area of Maharashtra.
Mohapatra said, even for Saurashtra, Kutch and Rajasthan, the reason for heat wave conditions is southerly winds.
The IMD records show that the maximum temperatures recorded on March 14 were around 39-41 degrees Celsius over many parts of Gujarat and west Rajasthan, and 38-40 degrees Celsius over some parts of southeast Rajasthan, Vidarbha, Konkan, and Goa.
Heat wave conditions in some pockets with severe heat wave conditions in isolated pockets was observed over Saurashtra-Kutch, heat wave to severe heat wave conditions was observed in some pockets over Konkan-Goa and west Rajasthan and heat wave conditions in isolated pockets over Gujarat region.
Why is Mumbai experiencing a heat wave?
The warm conditions in Mumbai, and the Konkan at large, is because the region is under the direct influence of the prevailing heatwave in the adjacent Saurashtra-Kutch regions of Gujarat.
