Kolkata: Propelled by the intense spells of rain under the impact of cyclone Remal, Kolkata has already received about 26% of its annual average rainfall, even before the onset of monsoon. While Tuesday remained largely dry, the Met office has not ruled out thundershower spells towards the weekend. Though of lower intensity, these rain spells may prevent the mercury from shooting up abruptly.
According to IMD data, Kolkata’s annual rainfall is pegged at 1,661 mm, with a mean May rain count of 118.5 mm. This May, the city has already logged 435.3 mm rain, close to 200 mm triggered by Remal between Sunday and Monday. The May rain amount has also already surpassed the mean rain count for the month.
“It is not unusual for a vast deviation in the May rain amount from the month’s mean rainfall. May is known for cyclones and severe thundershowers, like nor’westers. These systems can sometimes cause massive deviation from the month’s mean rain amount,” said H R Biswas, head of the weather section at Regional Meteorological Centre (RMC) Kolkata.
While the date for onset of monsoon in Kolkata and other parts of south Bengal is estimated to be between June 10 and 11, with an error margin of four days on either end, May is the month when the city should get local thundershower spells and pre-monsoon showers. Climatologically, the city should have 6.2 rainy days in May, including 2.2 squall days, under normal conditions.
The city got the year’s first nor’wester break on May 7, when a sharp spell of 71 mm rain brought a respite from the heatwave conditions citizens had to endure.
With 435.3 mm rain, May 2024, so far, is also the rainiest May in the past five years, with Monday clocking the second highest single-day rain count in the period at 189.6 mm. The highest was on May 21, 2020, when the city received 236.3 mm rain.
Intense rain with squally wind during Remal’s passage close to the city had dragged the maximum temperature down by around nine degrees on Monday, when it stood at 26.6°C. The minimum temperature was 25°C.
With rain spells coming to a halt by Monday afternoon, the mercury has started rising. On Tuesday, Kolkata recorded a maximum temperature of 33°C, which was two notches below normal. The Met office has predicted a sli-ght rise in temperature in the coming days. “While the rise in mercury will not be sharp, people could feel the discomfort due to high humidity. The city is getting southerly wind and we are not ruling out isolated rain spells,” Biswas said.
The maximum in the next few days may hover around the normal mark of 34°C while the minimum could swing between 27°C and 28°C.