South Asia to receive ‘above normal’ rainfall this year: Weather experts

“Except some northern and north, east and northeastern-parts, above-normal rainfall is expected over South Asia during June to September season this year. The seasonal rainfall is most likely to be normal,” the SASCOF rainfall outlook 2024 consensus stated.

This year’s southwest monsoon outlook consensus statement was jointly prepared by weather scientists representing nine national meteorological and hydrological services in this region.

The blue shaded areas in the South Asia will receive ‘above normal’ rainfall. (Source : SASCOF – 28 Consensus Statement)

The SASCOF rainfall forecast is in line with the first stage southwest monsoon rainfall forecast released by the India Meteorological Department (IMD) a fortnight ago.

Most of Pakistan, India, Sri Lanka, Nepal, Bangladesh and central Bhutan will receive normal or above rainfall during the southwest monsoon season. Normal rainfall is predicted along Afghanistan, remaining areas of Bhutan and large parts of Myanmar, except its southwest coast, the experts who participated in SASCOF-28 said.

Aiding good rainfall in the upcoming season, the SASCOF forum said, were multiple favourable ocean-atmospheric factors. The ongoing El Nino conditions, which commenced in June last year, was weakening.

“Currently, moderate El Nino conditions are prevailing along the equatorial Pacific Ocean. The conditions are likely to weaken further and El Nino Southern Oscillation (ENSO) neutral conditions shall develop during the early part of the monsoon. Thereafter, La Nina conditions are likely to develop during the second-half of the monsoon season,” SASCOF statement said.

El Nino is the warmer-than-normal sea conditions prevailing along the equatorial Pacific Ocean and is known to suppress the summer monsoon rainfall over India. On the contrary, La Nina is the cooler sea conditions over the same region and is associated with normal or above rainfall during the southwest monsoon season.

There is a strong likelihood that the Indian Ocean Dipole (IOD) — the counterpart of the Pacific Ocean’s ENSO in the Indian Ocean — would enter a positive phase, which positively influences the southwest monsoon over the region. At present, IOD is in its neutral phase. The sea surface temperatures naturally swing from El Nino, ENSO neutral and La Nina from time-to-time.

Along with India and Bangladesh, many South Asian countries are experiencing extreme heat. The SASCOF forecast on temperatures suggested that during the ongoing summer season, above normal day temperatures will be recorded over most regions. West Afghanistan, northern and eastern Pakistan and adjoining Gujarat-Rajasthan, northern Maharashtra, coastal Karnataka and Kerala, Lakshadweep, southwest Sri Lanka,Nepal, Bhutan along with central and southern Myanmar will be among the worst affected areas.

Along with officials from IMD, other participants in the Pune meet included experts from the World Meteorological Organisation, Japan Meteorological Agency, Korean Meteorological Agency, Meteorology Office, UK, International Research Institute for Climate and Society, Regional Integrated Multi-hazard Early-warning System, Lead Centre of LRFMME and the Indian Institute of Tropical Meteorology.