A stretch of Theatre Road waterlogged after the afternoon rain on Thursday that Met officials say could be the first in a series of scattered showers over the next 48 hours. A Telegraph picture

Monsoon is receding but the rain clouds that promised much and delivered little through the season might yet hold a surprise shower or two to make October seem like the July Calcutta didn’t have.

Thursday afternoon brought one such spell of lashing rain that lasted around an hour and tapered off to a steady drizzle till sundown, dragging down the Celsius to a notch below normal for the first time in a fortnight.

More rain has been forecast for the next 48 hours because of a low-pressure trough stretching from Bihar to the Bay of Bengal. “This trough is sucking in a lot of moisture from the sea, resulting in the formation of thunderclouds. That is why today’s rainfall was accompanied by thunder,” said G.C. Debnath, director of the Alipore Meteorological Centre.

The drainage network in parts of the city crumbled as usual on Thursday — Alipore recorded 48.7mm and Dum Dum 19mm of rain till 5.30pm — but the effect of the rain on the Celsius compensated for it. “I didn’t mind the rain at all, although I wasn’t prepared for it. It was getting very hot for this time of the year,” said engineering student Anirban Roy Chowdhury, who got drenched on his way home.

The maximum temperature, which had been in the 34 to 35 degrees Celsius range over the last few days, dropped to 32.3, a degree below normal.

The rain was heaviest in and around Kalighat — 80mm between 2.30 and 4pm — but it was Ballygunge that bore the brunt of waterlogging. Knee-deep water at Deshapriya Park, Lake Market, Ballygunge Place, Camac Street and Panchanantala slowed down traffic.

Parts of Southern Avenue, Rashbehari Avenue, Triangular Park, Sunny Park, Dover Lane and Chetla were also flooded but the water drained out within an hour of the rain receding.

It poured less in the northern part of the city, with Ultadanga and Palmer Bazar receiving 33mm of rain to Topsia and Dhapa’s 60mm. A few inbound flights were forced to hover over the airport for around 10 minutes because of low visibility.

The Met office said Thursday’s downpour wouldn’t be counted as monsoon rain. “Monsoon has not withdrawn yet (it is regarded as active from June 1 to September 30 in the entire country) but today’s rainfall was primarily caused by the low-pressure trough,” a weather scientist said.

The Alipore centre has recorded 51.6mm of rain in the first four days of the month, which is already more than double of last year’s October count of 23.5mm.

“Debasish had started his career as a contractual engineer with Bridge and Roof (a central undertaking) and was posted in Haldia. After his marriage in 2008, he took a new job and shifted to Punjab with wife Madhurima. We learnt about the differences between them after they came in January 2011 on a holiday,” said Debasish’s sister Sraboni.

According to her, Madhurima had gone straight to her parent’s house in Shyambazar, while Debasish came to Howrah. “A month later she sent a lawyer’s letter seeking mutual divorce. My brother went back to Punjab hoping things would settle down. But in March, Madhurima came to our house with Chaitali and a few others and demanded divorce,” recalled Sraboni.

Debasish came back to Howrah after quitting his job and met Chaitali to request her not to interfere in the family affairs. The discussion — in April 2011 — turned ugly.

While Debasish took up a job in Paradip and left in May, Madhurima lodged a complaint with Chatterjeehat police station under IPC Section 498A (torture) on September 29. Two days later, the Deys surrendered in court. Sraboni and her mother got bail but Debasish had to spend 26 days in judicial custody. The case is pending.

“Chaitali ruined our family but my brother did not get her killed,” said Sraboni.

RAIN GAUGE

• Thursday’s rainfall exceeded the entire October count of 2009 (47.9mm) and 2011 (23.5mm)

• June and July are rainier but October has already beaten the two in terms of highest rainfall in a single day