Coastal station weather is remarkably different from the inland locations. Farther the station from the coast, larger is the variance of meteorological conditions. India has a coastline of over 7,500km, from Gujarat to Kerala on the western side and Tamil Nadu to West Bengal on the eastern side. Weather conditions differ significantly on either side of the coastline even along the same latitude. Chennai is far different and much hotter than Mumbai throughout the year.
The question which invariably intrigues many minds is: Do the coastal station ever sizzle at 40 degrees and what is it for Mumbai. The answer is - yes, coastal stations do touch 40 degrees mark, albeit on few and freak occasions only.
After cessation of winters over Mumbai start shooting and aiming high 30's. It happened this February also when heatwave conditions prevailed over Mumbai and temperature rose to 38.1 degrees on 17th Feb and again 38.4 degrees on 27th Feb. Unlike in other parts of the country, with the pre- Monsoon grip getting tighter, the temperature soar to record high in May and early June, over the central and northern parts of the country. However, Mumbai keeps aloof from this and we find Feb end and March become equally hot and comparable to April and May. The pre- Monsoon season is actually more predictable for Mumbai. For six months, from November to April, the financial capital remains nearly dry. Showers come up only when the fragrance of Monsoon gets nearer in the second half of May. There is a marginal difference in the average temperature for Mumbai in the pre- Monsoon. During March, April and May, the normal temperatures are 32.8, 33.2 and 33.6 degrees respectively. It means less than 1-degree variation against 6-10 degrees over many parts of north and central India.
The capital city has not recorded 40 degrees in April in the last 10 years i.e. 2010 to 2019. The highest recorded is 39 degrees on 22nd April 2014 and the last three years orbited around 36 degrees only. This year so far, the highest in April is 35.7 degrees on 12th April. We do not see it climbing beyond 37 degrees in the remaining days of April. An offshore anticyclone in the Arabian Sea is fanning moist winds along the Konkan coast, suppressing the heat. This nearly becomes a semi-permanent feature with a marginal shift here and there during the entire season. Displacement of this feature towards May end or June makes way for the onset of the Southwest Monsoon.