The heatwave has ended, for now, in south Bengal, but more thunderstorms are in store, said the Met office.

The day temperature has come down and is unlikely to shoot up again this week. When it does not rain, hot and humid conditions will prevail, said a Met official.

A cyclonic circulation persists over the south Andaman Sea, said an IMD report. The system has already unleashed a barrage of “reports” saying it will intensify into a cyclone. Some of them have already predicted its path. WhatsApp groups are already brimming with such forwards.

The Regional Meteorological Centre in Alipore issued a stern clarification on “misinformation” on Wednesday. “IMD has never mentioned any cyclone.... IMD in its bulletin and briefing, mentioned a cyclonic circulation only over the Andaman Sea,” it said.

Ideal sea surface temperature and suitable wind shear (change in speed and direction of wind) are among the factors that determine whether a system can turn into a tropical cyclone.

The tropical weather outlook on the IMD website on Wednesday discounted the possibility of a depression in the Bay for the next seven days. The outlook is updated daily when a system is active near the Andaman Sea.

“Monsoon has also set foot in the region. The system has played a part in that. There is still nothing to suggest that it will turn into anything,” said a Met official.

The Andaman and Nicobar Islands and the surrounding waters are getting uniform, widespread, and, in many areas, heavy rain, said the official.

Closer home, Wednesday saw a maximum temperature of 35.3 degrees, just under normal, in Alipore. The minimum temperature had dropped to 23.5 degrees on Tuesday because of a squall the night before. Tuesday night was breezy. On Wednesday, the minimum temperature rose to 28.8 degrees.

A Met bulletin on Wednesday said an upper air cyclonic circulation over east Bihar and north Bengal, and a north-south trough from the circulation was behind the ongoing and imminent showers in the state.

Several parts of north Bengal got rain and wind on Wednesday, and so did some districts of south Bengal.

A Met official in Alipore said a squall was due in Calcutta by Thursday night.

“Enhanced thunderstorms with heavy rainfall activity are likely over some districts of north Bengal, and thunderstorms with gusty winds activity are likely over some districts of south Bengal,” the bulletin said.