Wettest monsoon in a decade, Met records show

New Delhi: The city is likely on its way to break the record for the wettest monsoon ever, said forecasters as light to moderate showers throughout the day on Friday helped the Capital breach the 1,000mm rain mark for the first time in over a decade, data from the weather office showed.

Data available with the India Meteorological Department (IMD) shows that so far this monsoon, Delhi has received 1,015.5mm rain after parts of the city received showers early Friday morning and in the evening.

According to the data maintained by the Met department, Delhi last experienced a wetter monsoon in 2010, when the city received 1,030.5mm rain.

“Thunderstorm with moderate to heavy rains, along with winds at a speed of 30-60kmph, is likely over parts of Delhi and NCR starting Friday night. This will continue on Saturday and Sunday,” said the IMD forecast.

Met officials said with a forecast of moderate to heavy showers in Delhi-NCR during the weekend, the Capital will “easily surpass” the 2003 record for the wettest monsoon.

“Delhi will break its rainfall record for 2010. We will have to see what the new record is going to be. We still have time before the monsoon withdraws,” said RK Jenamani, senior scientist at IMD.

Despite a late-onset, the monsoon this year has seen some erratic, record-breaking patterns. The monsoon officially arrived in the national capital on July 13, after a delay of 16 days instead of its usual onset on June 27. The resultant rainfall, arising from the late arrival of monsoon was, however, covered with only a few spells of heavy rain, with July receiving 507.1mm rain, compared to the normal precipitation of 210.6mm, and recording a surplus of 141%.

In August, monsoon patterns changed again when the city experienced two spells of break monsoon. IMD officials said one such spell of break monsoon lasted for 10 days, making it one of the longest dry spells the city has ever seen in the monsoon season.

In August, Delhi received 214.5mm rainfall against the average monthly precipitation of 247.7mm. The rainfall trends changed again in September. Unlike August, which by and large remained dry due to the break monsoon, Delhi recorded eight rainy days between September 1 and September 10 with the rainfall recording standing at 248.9mm against the normal of 62.6mm for those 10 days. The overall monthly average rainfall for September is 125.1mm. Last September, Delhi’s rainfall recording was only 20.9mm for the whole month.

Weather forecasters said extreme monsoon recordings this season were an impact of global climate conditions as well as local factors that played a part this year.

“This will be one of the wettest monsoons Delhi has ever seen. The city is just short of 30mm rain, which will be covered by a single spell of rain,” said Mahesh Palawat, vice-president (meteorology and climate change), Skymet Weather Services, a private weather forecasting centre.

Explaining what caused these extreme recordings this monsoon season, Palawat said, “Earlier, we used to see that the low-pressure areas that formed in July and August used to go till Gujarat, and because of this, Delhi did not receive much rain. We have observed in the last few weather systems that the low-pressure areas reached only till Uttar Pradesh. The closer a low-pressure area is, the higher the intensity of the rainfall in a region. Hence, Delhi didn’t get enough rainy days this year, the intensity of rain spells was high.”