New Delhi, Aug. 11 -- After a fairly dry start to the year, which saw only 10.5mm of rainfall recorded in the first four months of the year, Delhi has since then received nearly 700mm of rainfall, pushing it close to the normal annual rainfall mark of 774.4mm. Heavy rain in most parts of the city on Saturday took Delhi's annual rainfall total to 706.7mm-over 91% of the annual rainfall mark. More rain spells in August are likely to cover this mark, with four months to spare, much like last year, when this mark was eclipsed in a rainy August. Experts attributed the phenomenon to a combination of active weather systems dominant in northwest India, aided by an equally active monsoon this time around. "Last year, we had La Nina conditions, which was driving the monsoon. This time, there are neutral conditions, but we have had a lot of active weather systems dominating northwest India. This has kept the plains particular fairly wet, with light to moderate spells on most days and heavy spells on isolated days," said Mahesh Palawat, vice president at Skymet. Last year, Delhi crossed the annual rainfall mark on August 30, buoyed by a monthly total of 390.3mm in August. It had three times the normal rain in June (243.3mm) and almost normal rain in July (203.7mm), data showed. In comparison, Delhi has seen excessive rainfall this year in every month since May. In fact, May was the wettest ever on record, with 186.4mm of rainfall recorded, which is over six times the normal average of 30.7mm. In June, Delhi recorded 107.1mm of monthly rainfall, an excess of 45% over the long-period average (LPA) of 74.1mm. In July, Delhi received 259.3mm of rainfall, which was 24% more than the LPA of 209.7mm. With 143.4mm of rainfall already recorded this month, August is also on track to reach or eclipse the normal mark of 233.1mm. "We are expecting some active spells in the next 10 days or so. While the monsoon trough is again in the foothills, it is expected to return close to Delhi on August 13 due to a low-pressure area. Until August 20, we will have on and off rains, so excess rain in August for Delhi is also a possibility," Palawat said. While Delhi has only recorded four "heavy" rainfall days-64.5mm to 115.5mm of rainfall in a 24-hour period-so far this season, extreme weather events, including spells of squally winds, have been a common occurrence, wreaking havoc on the city and leading to infrastructure collapse and deaths. The Capital received the first heavy rainfall spell of 77mm on May 2, followed by a season-high 24-hour spell of 81.4mm on May 25. It logged 68.1mm on July 29 and 79mm on Saturday. However, May recorded at least five extreme weather events, with dust storms on May 15, 17 and 21, as winds touched speeds close to 80 km/hr. The spells on May 2 and 25, similarly, had maximum speeds of 80 and 82km/hr, respectively. June, which failed to record a single heavy rainfall spell, also had two intense thunderstorm spells. On June 1, winds of up to 96km/hr and 15.8mm in rainfall were recorded, followed by a spell on June 15, when the winds touched a speed of 104km/hr, bringing along with it 42mm of rainfall. An IMD official attributed it to active weather systems, including low-pressure areas and western disturbances. "We have had a fairly active pre-monsoon period, which has continued into the monsoon season," the official said. Palawat, meanwhile, said four heavy rainfall days were normal for this period, but with the monsoon expected to bring more rain in August and September, this number may rise further. "Models indicate we should see active weather systems persist in these two months," he said. No rainfall was recorded in the city on Sunday. The IMD has forecast patchy and light spells of rainfall on both Monday and Tuesday, with light to moderate showers expected on Wednesday....