After days of intense heat and people scorching in uncomfortable humidity, Kolkata is set to witness a drastic weather shift, with the India Meteorological Department (IMD) forecasting enhanced thunderstorm activity across the state between April 5 and April 9. It is also expected to be the onset of seasonal Kalbaishakhi storms, bringing rain, lightning and gusty winds to several districts.
According to a special bulletin issued by IMD, hot and humid conditions prevailed across South Bengal on Saturday, driven by dry winds and high moisture levels. Coastal districts recorded relative humidity levels of 80-90 per cent, increasing discomfort. However, weather officials indicate that this build-up of heat and moisture has created favourable conditions for thunderstorm development in the coming days.
In Kolkata and the adjoining districts of Howrah, Hooghly, and the two 24 Parganas, thunderstorms accompanied by gusty winds of 40-50 kmph and lightning are expected between April 6 and April 9. The IMD’s district-wise forecast indicates that rainfall activity will become more intense mid-week.
A gradual drop of 3-4 degrees in day temperatures is expected over the next 24 hours, offering some relief from the prevailing heat. The cooler conditions are reported due to sustained rainfall and cloud cover across the region.
In Kolkata, the next 24 hours are expected to see mainly clear to partly cloudy skies, with a chance of thundery development by afternoon or evening, as temperatures hover between 36-37 and 26-28 degrees Celsius amid high humidity and no recorded rainfall.
From Sunday, thunderstorm activity is expected to gradually intensify, initially affecting districts such as Purulia, Bankura, Jhargram and West Midnapore, before spreading to other parts of South Bengal, including Kolkata, from April 6 onward.
The IMD has forecast light to moderate rain accompanied by thunderstorms and lightning across most districts, with wind speeds generally ranging between 30 and 50 kmph. A yellow alert has been declared.
During the peak phase between April 7 and April 8, gusty winds may reach up to 60 kmph in some areas, particularly in districts such as Bankura, East and West Burdwan, Birbhum, and Murshidabad. There is also a likelihood of hailstorms in isolated places, including Bankura, East Burdwan, and Birbhum, indicating a potentially intense Kalbaishakhi spell after a phase of hot, humid weather.
North Bengal districts are also expected to witness a similar trends. Districts such as Darjeeling, Jalpaiguri, Coochbehar and Alipurduar may experience thunderstorms with wind speeds from 30-40 kmph and reaching up to 60 kmph, along with heavy rainfall (7–11 cm) and hailstorms in some areas, particularly in the Darjeeling and Jalpaiguri districts, between April 7 and April 9. An orange alert has been issued for these regions during this time period as well.
To avoid heat strokes, avoid prolonged outside exposure and work during 11 am to 4 pm. Drink sufficient water to avoid dehydration. Weather officials have instructed to practice caution due to possible lightning strikes, damage to temporary structures, falling tree branches, and disruptions to power and communication lines. Urban areas may also experience traffic disruptions and reduced visibility during intense spells.
Authorities have advised residents to remain cautious during thunderstorm activity, avoid open areas, and take necessary precautions against lightning. With Kalbaishakhi storms approaching, the coming week will bring both relief from the heat and risks associated with intense weather across the state.