A fresh system is imminent over the Bay of Bengal, but this time, it is likely to cause more rain in Andhra Pradesh and Odisha, said Met officials.
Heavy rain is likely to continue in north Bengal for now. But once the system takes shape, the trough, which is passing through Jalpaiguri now, will descend and the showers will lose steam, they said.
“A low-pressure area is likely to form over the northwest and adjoining west-central Bay of Bengal on Wednesday. The southeastern coastline in Andhra Pradesh and Odisha will be affected more by the system than Bengal. Light to moderate rain is likely in some parts of south Bengal,” said H.R. Biswas, head of the weather section at the Regional Meteorological Centre in Alipore.
This year, the monsoon so far has been marked by successive systems over the Bay and neighbourhood. Each one of them has caused significant rain in south Bengal, including Calcutta.
As of now, the imminent system is likely to bring only a cloudy sky and sporadic rain in Calcutta during the Independence Day weekend.
Dark clouds descended on Calcutta on Monday afternoon following a hot and humid day. But only some parts of the northern fringes received a sharp spell of rain. When Nagerbazar, Paikpara and parts of Salt Lake were caught up in blinding rain, Esplanade was bone dry. The monsoon trough now passes through Punjab, Uttar Pradesh, Bihar and Jalpaiguri in north Bengal before wading into the Northeast.
“The monsoon currents are weak in south Bengal. They are active in Sikkim and the sub-Himalayan Bengal. But when the low-pressure area takes shape, the trough is expected to come down,” Biswas said.
Until that happens, heavy to very heavy rain (7-20cm) is expected in north Bengal. Some areas in Alipurduar and Jalpaiguri may get more or “extremely heavy” rain.
The rains are likely to subside in north Bengal from August 14.
Heat and humidity have been taking a toll on Calcuttans for the past few days.
On Monday, the maximum temperature was 34.7 degrees, more than two notches above normal. Around 1pm, the Celsius was around 33 degrees, but the humidity of 70 per cent made it feel like 40 degrees.