June date likely for La Nina as conditions shift
Conditions have turned favourable for the La Nina weather phenomenon in the tropical Pacific Ocean to start in the next six months, the Climate Prediction Centre of the National Oceanic and Atmospheric Administration of the US has said, which could lead to above normal rainfall and floods in India during the southwest monsoon that starts in June.
The weather phenomenon will most likely begin in June and July, the centre said, which was in line with the prediction of the Monsoon Mission Coupled Forecasting System of India’s weather bureau. There are favourable conditions for La Nina to develop during the monsoons, the India Meteorological Department said.
“We’ve seen a quick switch from El Nino to La Nina several times before in our 1950-present record, especially after a strong El Nino. This tendency is one source of confidence in the prediction that La Nina will develop later this year,” the US scientific agency said.
The El Nino, a rise in sea surface temperatures in the Pacific, was at its strongest between November and January, the World Meteorological Organisation had said in March. At its peak, it was about 2 degrees Celsius above the 1991 to 2020 average sea surface temperature for eastern and central tropical
Pacific Ocean, which made it one of the five strongest El Nino events ever.
“It will take a few months to transition to the La Nina threshold and establish itself,” said DS Pai, head of the climate service division at India’s weather office.
“With the establishment of La Nina sometime during the monsoon, we can expect flooding rains in parts of the country, including the west coast, the Himalayan foothills and the core monsoon region in central India.”
The weather bureau has already forecast above normal monsoon at 106% of the long-period average.
The change in the climatic pattern is expected to create conditions for a good monsoon, according to Mahesh Palawat, vice president of climate change and meteorology at Skymet Weather Services, a private forecaster.
“Heatwave conditions will also be relieved,” he added. “Due to ongoing western disturbances, we are also not expecting any heatwave conditions over northwest India immediately.”
In India, an El Nino is associated with a harsher summer and weaker monsoon. La Nina, on the other hand, is associated with a strong monsoon and above average rains and colder winters in the subcontinent.