Pune: Between July 1 and July 8, Pune had the wettest start to the month in 57 years, with IMD’s Shivajinagar observatory recording 393.9mm of rainfall.IMD scientist SD Sanap said records dating back to 1969 show that the previous highest rainfall for the first eight days of July was 228mm in 2007. This year’s total of 393.9mm beat that record by nearly 166mm, making it the highest rainfall recorded during July 1-8 since records began in 1969. The record-breaking 393.9mm pertains to rainfall received till 8.30am on July 8. With another 15.1mm recorded on Wednesday, Shivajinagar’s July rainfall climbed further to around 409mm.“This monthly total has already exceeded the highest rainfall recorded during the entire month of July in at least the last decade,” said one expert from the Vagaries of Weather blog. IMD data shows Shivajinagar had received 394mm in July 2024, earlier the wettest July in the past 10 years. This year’s total has already crossed that mark with more than 20 days to spare.July rainfall totals at Shivajinagar over the past decade have been 62mm (2015), 223.3mm (2016), 194.2mm (2017), 175.6mm (2018), 369.1mm (2019), 119.8mm (2020), 193mm (2021), 386.2mm (2022), 154.5mm (2023), 394mm (2024) and 130.3mm (2025).Sanap said this year’s intense spell was a combination of favourable weather systems. “A low-pressure system over Bay of Bengal intensified into a depression and moved westwards across the country. At the same time, an offshore trough persisted along the west coast, while an east-west shear zone was positioned around 21 degrees north latitude,” he said, adding that the shear zone was located roughly along the latitude of Mumbai and adjoining regions.“This helped produce very heavy rainfall over north Konkan and Western Ghats. The Ghats received exceptionally heavy rainfall, which has been one of the major highlights of this spell,” Sanap said.Pune is on the leeward side of Western Ghats, but the city benefited from the prevailing weather pattern, he added. “Strong moisture was transported inland immediately after crossing the Ghats. Because of this sustained moisture incursion, Pune too received widespread and heavy rainfall despite being in the rain-shadow region,” Sanap said.The daily rainfall recorded at Shivajinagar during the first eight days of July this year was 5.3 mm on July 1, 11.4 mm on July 2, 25.3 mm on July 3, 30.5 mm on July 4, 30.7 mm on July 5, 108.4 mm on July 6, 97.5 mm on July 7 and 84.8 mm on July 8, taking the cumulative rainfall to 393.9 mm by Wednesday morning.Importantly, the IMD scientist said El Niño’s impact — forecast as very likely by world agencies — cannot be inferred from day-to-day weather events such as the current spell of heavy rain.“El Niño’s influence is assessed over seasonal rainfall rather than individual weather events. Two months of the monsoon remain. The present spell is due to synoptic weather systems, particularly the Bay of Bengal system and other favourable features. Intensity of El Niño is expected to increase from next month, so its impact on seasonal rainfall can only be assessed later,” Sanap said.
