123 Kolkata: A powerful squall hit the city on Thursday evening, accompanied by a thundershower spell. While passing through the Alipore observatory, the squall recorded a maximum wind speed of 59 kmph from a west-southwesterly direction between 6.30 pm and 9 pm.
While the thunderstorm helped keep the heat at bay, the wind speed, gusting up to 71 kmph in parts of the city, uprooted several trees across Kolkata. Trees were uprooted on some major throughfares, too.
The Met office has predicted more rain in the coming days, which will keep the city's weather pleasant for at least a week.
Although the rain during the squall was less than 3 mm, the duration of gusty wind, along with another gust from different directions, led trees to fall. According to Met parlance, one of the foremost criteria for a squall is that the wind must maintain a sustained speed of at least 45-50 kmph for at least a minute, accompanied by thunder, lightning and rain.
"While in terms of wind speed, the Thursday squall was slightly less in magnitude than what the city experienced last Saturday, what mattered this time was that there were other wind systems gusting from different directions, causing a kind of crosswind situation. In such situations, the damage to trees can be higher," said Met scientist H R Biswas, head of weather forecast section at RMC, Kolkata.
The first squall this season stormed the city on April 10 at a wind speed of 53 kmph, and the second one hit on April 26 at 62 kmph.
On Thursday, around the same time, Dum Dum also saw a squall with a wind speed of 53 kmph from a northwesterly direction, affecting parts of north Kolkata.
"For Kolkata, there is a good chance for a nor'wester spell on Saturday towards the evening. We can expect a spell or two on and off in next five days, which will ensure pleasant weather in the city. But from next weekend, we expect the mercury to be on a rising trend, where the rain spells will become less frequent until the first fortnight of May," added Biswas.