In India above normal rainfall most likely during Southwest Monsoon season
Secretary, Ministry of Earth Sciences, Dr M Ravichandran & DG, India
Meteorological Department, Dr Mrutyunjay Mohapatra informs the media
Seasonal rainfall likely to be 106 per cent of Long Period
Average (LPA) with a model error of ± 5 per cent, says IMD
Long range Forecast of rainfall for the 2024 South West monsoon season released
today by IMD
Northern hemisphere snow cover extent during the last three months (January to
March 2024) was below normal
Secretary,
Ministry of Earth Sciences, Dr M. Ravichandran told the media today that the
country as a whole is likely to receive above normal rainfall during the south
west monsoon from June to September 2024.
Briefing
the media about the summary of the 2024 Southwest Monsoon Season Rainfall today
in a press conference held at National Media Centre, New Delhi, he said there
will be 106% of the Long Period Average (LPA) with a model error of ± 5%. The LPA of
the season rainfall over the country as a whole is 87 cm based on data of
1971-2020.
Dr. Ravichandran
said, the forecast is based on both dynamical and statistical models, and it
suggests above normal rainfall is likely over most part of the country except
some areas of Northwest, East and Northeast India, where below
normal rainfall is likely. He told media that the
expected La Nina, positive IOD and below normal snow cover over northern
hemisphere would be favourable for rainfall during southwest monsoon season
2024.
Giving a detailed presentation DG, IMD, Dr Mrutyunjay Mohapatra said
that currently, moderate El Niño conditions are prevailing over
the equatorial Pacific region and the Climate model forecasts indicate neutral
condition by the beginning of monsoon season and La Niña conditions during
second half of monsoon season.
Probability
forecasts for the Seasonal (Jun to Sep, 2024) rainfall over country as a whole
is given below in table:
Since
2003, India Meteorological Department (IMD) has been issuing the operational
long-range forecast (LRF) for the southwest monsoon seasonal (June-September)
rainfall averaged over the country as a whole in two stages. The first stage
forecast is issued in April and the second stage or update forecast is issued
by the end of May. Since 2021, IMD has implemented a new strategy for issuing
monthly and seasonal operational forecasts for the southwest monsoon rainfall
over the country by modifying the existing two stage forecasting strategy. The
new strategy uses both dynamical and statistical forecasting system.
Multi-Model Ensemble (MME) forecasting system based on coupled global climate
models (CGCMs) from different global climate prediction centres, including
IMD’s Monsoon Mission Climate Forecast System (MMCFS) is used in dynamical
forecast system.
In continuation to the above forecasts, monthly rainfall
forecast is issued around the end of June, July and August respectively for the
subsequent one month. In addition, quantitative and probabilistic forecasts for
the country as a whole and spatial distribution of probabilistic forecasts of
rainfall for second half (August-September) of the season is issued around end
of July along with forecast for August.
Summary of the
Forecast of Rainfall during Southwest Monsoon Season, 2024 is as follows:
· The
rainfall over the country as a whole during monsoon season (June to September)
is very likely to be above normal (>106% of the Long Period Average (LPA)).
· Quantitatively,
the seasonal rainfall over the country as a whole is likely to be 106% of LPA
with a model error of ± 5%.
· The LPA
of the season rainfall over the country as a whole is 87 cm based on data of
1971-2020.
· Currently,
moderate El Niño conditions are prevailing over the equatorial Pacific region.
Climate model forecasts indicate neutral condition by the beginning of monsoon
season and La Niña conditions during second half of monsoon season.
· Currently,
neutral Indian Ocean Dipole (IOD) conditions are prevailing. Climate model
forecasts indicate positive IOD conditions likely to develop during the monsoon
season.
· Northern
hemisphere snow cover extent during the last three months (January to March
2024) was below normal. Winter and spring snow cover extent over Northern
Hemisphere as well as Eurasia has a generally inverse relationship with the
subsequent monsoon season rainfall.
· IMD will
issue the updated forecasts for monsoon season rainfall in the last week of May
2024.