Imprint of El Nino, other weather patterns on India’s deficit June 2026 rainfall

India's June 2026 southwest monsoon opened with a steep 40% rainfall deficit against the long-period average, the worst June performance in recent memory, wi...

What Happened

India's June 2026 southwest monsoon opened with a steep 40% rainfall deficit against the long-period average, the worst June performance in recent memory, with 76% of districts reporting deficient, large deficient, or zero rainfall by June 29.
The deficit is being driven by three converging factors: a strengthening El Niño (NOAA declared El Niño conditions on June 11, 2026), an unfavourable Madden-Julian Oscillation phase suppressing convective activity, and a near-total absence of low-pressure systems over the North Indian Ocean.
The southwest monsoon onset over Kerala occurred on June 4, 2026 — nine days later than the IMD's forecast of May 26 and three days later than the climatological normal of June 1.
Central India recorded the worst deficit at 50% below normal; East and Northeast India at 40%; Northwest India at 31%; Southern Peninsula at 27%.
Hardest-hit states include Meghalaya (76% deficit), Manipur (72%), Jharkhand (66%), and Chhattisgarh (66%), threatening the kharif season for an estimated 60% of farmers dependent on monsoon rainfall.

Static Topic Bridges

El Niño-Southern Oscillation (ENSO) and Indian Monsoon

El Niño is the warm phase of the El Niño-Southern Oscillation (ENSO) cycle, characterised by anomalous warming of sea surface temperatures (SSTs) in the central and eastern equatorial Pacific Ocean. The coupled ocean-atmosphere system oscillates between the warm (El Niño) and cold (La Niña) phases on an irregular 2–7 year cycle.

During El Niño, the Walker Circulation weakens: warm water shifts eastward in the Pacific, reducing convective activity over the Indian Ocean and suppressing monsoon rainfall over India and the subcontinent.
El Niño years historically correlate with below-normal Indian monsoon rainfall; approximately 60% of El Niño events are associated with deficient monsoon (below 90% of long-period average).
India's long-period average (LPA) for monsoon rainfall is approximately 87 cm over June–September.
La Niña (cold phase) typically enhances Indian monsoon rainfall.
Monitored by NOAA (USA) and the Bureau of Meteorology (Australia); declared when the Oceanic Niño Index (ONI) exceeds +0.5°C for at least five consecutive overlapping three-month periods.
NOAA declared El Niño on June 11, 2026, with projections of the event persisting into the Northern Hemisphere winter of 2026–27 and potentially becoming a very strong event.

Connection to this news: The 40% June deficit is directly linked to the ongoing El Niño suppression of Indian Ocean convection and monsoon circulation. UPSC frequently asks students to explain the mechanism by which El Niño weakens the southwest monsoon.

Madden-Julian Oscillation (MJO)

The Madden-Julian Oscillation (MJO) is the dominant mode of intraseasonal variability (ISV) in the tropical atmosphere, operating on a 30–60 day cycle. It was first identified by Roland Madden and Paul Julian in 1971–72.

The MJO is characterised by an eastward-propagating pulse of enhanced (active) and suppressed convection, moving from the western Indian Ocean toward the central Pacific over 30–60 days.
During its active (convective) phase over the Indian Ocean, the MJO significantly enhances Indian monsoon rainfall; during its suppressed phase, it weakens monsoon activity.
Of total intraseasonal variability in the Asian summer monsoon, 50–80% is attributed to MJO influence.
A suppressed MJO phase over or near the Equator (as in June 2026) reduces moisture convergence and limits the development of low-pressure systems — the primary rain-bearing systems for much of India.
The MJO is measured via the Real-time Multivariate MJO (RMM) index, which tracks its position and strength across eight phases.

Connection to this news: The unfavourable MJO phase in June 2026 compounded El Niño suppression: with the MJO in a suppressed state near the Equator, the energy needed to sustain monsoon intra-seasonal oscillations and generate low-pressure systems was absent, amplifying the rainfall deficit.

India Meteorological Department (IMD) and Monsoon Forecasting

The India Meteorological Department (IMD), established in 1875, is the national meteorological service of India and the principal government agency for weather observation, forecasting, and monsoon monitoring. It operates under the Ministry of Earth Sciences.

IMD issues the official Long Range Forecast (LRF) for the southwest monsoon each April, with an update in May/June.
IMD uses a statistical-dynamical ensemble forecast model, incorporating ENSO indices, Indian Ocean Dipole (IOD), and other predictors.
IMD defines "normal" rainfall as ±10% of the LPA; "deficient" as 20% or more below LPA; "large deficient" as 60% or more below LPA.
The southwest monsoon typically enters Kerala by June 1 (with a standard deviation of about 7 days) and covers all of India by mid-July.
IMD declared El Niño conditions as a risk factor in its 2026 forecast, predicting below-normal rainfall at 90% of LPA.

Connection to this news: IMD's forecast of below-normal rainfall at 90% of LPA was borne out: actual June 2026 rainfall fell 40% below normal. The delay in monsoon onset over Kerala (June 4 vs normal June 1) was flagged as an early indicator of a weak monsoon season.

Southwest Monsoon: Mechanism and Agricultural Significance

The southwest (SW) monsoon is the principal rainy season of India, delivering approximately 75% of the country's annual rainfall over June–September. It is driven by the differential heating of land and sea and the associated pressure gradient.

Origin: The SW monsoon is driven by the low-pressure area that develops over the heated Indian subcontinent in summer, drawing moisture-laden winds from the Southwest Indian Ocean.
The monsoon arrives in two branches: the Arabian Sea branch (hits the Western Ghats first) and the Bay of Bengal branch (moves up eastern India and the northeast).
Low-pressure systems (depressions, deep depressions, cyclonic storms) originating over the Bay of Bengal and the Arabian Sea are critical drivers of inland rainfall, particularly for central India.
India's kharif crops (paddy, cotton, soybean, pulses, oilseeds) are almost entirely rain-fed; a 40% deficit in June threatens sowing and raises food inflation risks.
The deficit threshold for declaring an agricultural drought varies by state, but a national deficit exceeding 20% of LPA over the monsoon season is typically considered a drought year.

Connection to this news: The absence of low-pressure systems over the North Indian Ocean — identified as a key cause of the June 2026 deficit — is a direct manifestation of weakened monsoon circulation under El Niño and suppressed MJO conditions. Central India's 50% deficit threatens the kharif sowing season across major agricultural states.

Key Facts & Data

June 2026 national rainfall deficit: 40% below the long-period average (LPA).
76% of Indian districts reported deficient, large deficient, or zero rainfall by June 29, 2026.
Regional deficits: Central India −50%, East & Northeast −40%, Northwest India −31%, Southern Peninsula −27%.
Worst-hit states: Meghalaya −76%, Manipur −72%, Jharkhand −66%, Chhattisgarh −66%.
Southwest monsoon onset over Kerala: June 4, 2026 (normal: June 1; IMD forecast: May 26).
NOAA declared El Niño on June 11, 2026; projected to persist into Northern Hemisphere winter 2026–27.
India's long-period average (LPA) for monsoon rainfall: approximately 87 cm over June–September.
IMD's pre-season forecast for 2026 monsoon: below-normal at 90% of LPA.
Approximately 60% of India's farmers depend on monsoon rainfall for kharif cultivation.
MJO cycle: 30–60 days; responsible for 50–80% of intraseasonal variability in Asian summer monsoon.
ENSO cycle periodicity: 2–7 years; warm phase = El Niño, cold phase = La Niña.