Monsoon is over. But why is it raining so much in October? Here's the answer
From north to south, many states in India are witnessing heavy rainfall in the month of October, even after the India Meteorological Department (IMD) said the southwest monsoon has completely withdrawn from most of north India.
In Delhi, October has emerged as the wettest month since 1960. In Uttarakhand, nearly 50 people have died due to landslides triggered by heavy rainfall, which also blocked key highways. In Kerala, the authorities had to open gates of a number of dams due to water levels breaching danger marks.
So what is the reason behind this sudden downpour? According to IMD, an unusual western disturbance - a rain system that originates in the Mediterranean region - swept across the northern plans and slammed into the Himalayan ranges, triggering extremely heavy rain spells often regarded as cloudbursts.
"A western disturbance interacted with the easterlies to cause conditions for extremely heavy rain over Uttarakhand. There was a low-pressure area over Bihar which was bringing in a lot of moisture and the western disturbance helped cloud development and rain," said DS Pai, Scientist and head of climate research and services.
And then there was the impact of climate change. “Climate change has increased moisture holding capacity of the atmosphere all around the world. So of course, climate change has a role to play but also local synoptic features need to be considered,” Pai added when asked about reports of cloudburst in Ramgarh block, about 35km from Nainital town.
He also said that in the post-monsoon period, such intense rainfall events occur in Maharashtra also.
The IMD has forecast more rainfall for Odisha and West Bengal, which have already been pounded by low pressure area-induced heavy showers over the past three days, throwing life out of gear in places.
According to the Met department, the states will have to brace for downpour over the next two days, despite the low-pressure system having moved to Bihar.
Water levels in Subarnarekha, Budhabalang and Jalaka rivers in northern Odisha are on the rise, according to the weather department. The MeT office has issued a yellow warning for Sundargarh, Keonjhar, Mayurbhanj and Balasore. In West Bengal, it has warned of extremely heavy rainfall over Darjeeling, Kalimpong and Alipurduar till Wednesday and downpour till Thursday over all sub-Himalayan districts.
In Kerala, shutters of Cheruthoni dam, part of the Idukki reservoir in Kerala, were opened on Tuesday to create more storage capacity after IMD forecast of more rainfall over the next two days. The gates of Idamalayar dam in Ernakulam and Pampa in Pathanamthitta were also opened in the morning as water in these reservoirs had almost reached the danger levels.
The weather department has issued orange alerts for 11 districts, barring Kollam, Alappuzha and Kasaragod, on Wednesday and 12 districts, except Kannur and Kasaragod, on Thursday.
The extreme rain was triggered by a depression in the Arabian Sea, which caused its effect over Kerala. Rain-related incidents have claimed 38 lives across the state.