IMD November 2026 Forecast: Below-Normal Northeast Monsoon Rain, El Niño and Rabi Impact

What happened

On 31 October 2026, the India Meteorological Department (IMD), under the Ministry of Earth Sciences, released its Monthly Outlook for Rainfall and Temperature for November 2026. The headline: November rainfall is most likely to be below normal (less than 77% of the Long Period Average, LPA) both over South Peninsular India and over the country as a whole.

IMD also expects above-normal maximum and minimum temperatures over most of India, says very strong El Niño conditions are prevailing over the equatorial Pacific and likely to continue in November–December 2026, and expects neutral Indian Ocean Dipole (IOD) conditions to continue till December 2026.

Background

Northeast monsoon. After the southwest monsoon withdraws, winds over south India turn easterly/northeasterly and bring the northeast monsoon (October–December, OND). IMD calls OND the post-monsoon season. In 2026, IMD's Regional Meteorological Centre, Chennai announced on 15 October that the southwest monsoon had withdrawn from the entire country and northeast monsoon rainfall had commenced the same day over Tamil Nadu, Puducherry & Karaikal, Coastal Andhra Pradesh, Rayalaseema, South Interior Karnataka and Kerala & Mahe.

Why it matters to the south. According to IMD, South Peninsular India (five meteorological subdivisions) receives about 30% of its annual rainfall in OND, and Tamil Nadu, Puducherry and Karaikal about 48%. IMD has issued seasonal forecasts for northeast monsoon rainfall over the south peninsula since 1998.

How IMD forecasts. Since 2021, IMD has combined its statistical models with a Multi-Model Ensemble (MME) of coupled global climate models from several centres, including its own Monsoon Mission Coupled Forecast System (MMCFS).

What the season forecast said. On 30 September 2026, IMD forecast OND rainfall over South Peninsular India to be normal (88–112% of LPA), against an OND LPA of about 334.1 mm (1971–2020). The 31 October outlook is the first month-level signal for the heart of the season, and it points the other way for November.

Key details

The five subdivisions of South Peninsular India: Tamil Nadu, Puducherry & Karaikal; Coastal Andhra Pradesh & Yanam; Rayalaseema; Kerala & Mahe; and South Interior Karnataka.

A detail worth noting on the IOD. The highlights of IMD's release describe the IOD as neutral, but its detailed text says the IOD index has currently exceeded the positive IOD threshold of +0.4 °C. Values must stay above the threshold for a sustained period before a positive IOD event is considered established, and IMD's MMCFS and other models still expect neutral conditions through the post-monsoon season (till December 2026).

Tercile categories. IMD's maps give the probability of three categories (above normal, normal, below normal), each with an equal climatological chance of 33.33%. The percentage limits for "normal" depend on the region and period: the OND season forecast for the south peninsula used 88–112% of LPA, while the November outlook marks below normal as under 77% of LPA.

Why it matters

• Water and farming in the south: November is a key month of the northeast monsoon. Tamil Nadu depends on OND rain for nearly half its annual rainfall, so a dry November affects reservoir storage and groundwater.
• Rabi sowing: IMD's 30 September release warned that below-normal rainfall during the rabi season could hurt soil moisture, water availability and farm productivity, raise irrigation needs and the chance of dry spells, and reduce reservoir and groundwater recharge.
• Warmer nights: above-normal minimum temperatures over most of India mean warmer nights in a month that usually marks the start of winter cooling.
• Climate drivers in action: the outlook is a live example of how El Niño and the IOD shape Indian rainfall, a favourite theme in UPSC and State PSC papers.

Issues and criticism

• Season vs month: the 30 September seasonal forecast was "normal" for the south peninsula, while the November outlook is "below normal". This is not a contradiction in itself, since October and December rain also count towards the season, but students should quote each forecast with its date.
• Limits of prediction: IMD's northeast monsoon forum document (Chennai, 1 October 2026) notes that seasonal predictability in this season is limited by strong day-to-day variability from disturbances in the easterlies and the Madden-Julian Oscillation (MJO).
• Mixed signals on the IOD: the index has crossed the positive threshold, yet IMD expects neutral conditions. Watch IMD's next updates rather than assuming a positive IOD.
• Climate change: the same IMD forum document says global warming is expected to raise the frequency and intensity of extremes such as heavy rainfall, dry spells and heat waves in the region.

Way forward

• Use IMD's shorter-range tools: IMD issues extended-range forecasts (7-day averages for the next four weeks) every Thursday, plus daily short- to medium-range forecasts; farmers and officials can plan sowing and irrigation week by week.
• Water budgeting: IMD has advised authorities to assess water availability, optimise irrigation, promote water conservation and keep agricultural contingency plans ready.
• Impact-based warnings: IMD recommends using its Impact-Based Forecasts and risk-based advisories for timely decisions.
• Track the next outlook: IMD will publish the December forecast and the December–February outlook at the end of November 2026.

Revise this week's events with the weekly current affairs quiz, and see the UPSC Prelims page for the syllabus.

Prelims pointers

• IMD's November 2026 outlook: rainfall below normal (<77% of LPA) for South Peninsular India and all-India.
• November LPA (1971–2020): about 118.7 mm for South Peninsular India; about 29.7 mm for all-India.
• OND (post-monsoon) LPA for South Peninsular India: about 334.1 mm; the 30 Sep 2026 forecast for the season was normal (88–112% of LPA).
• South Peninsula gets about 30% of its annual rain in OND; Tamil Nadu about 48%.
• In 2026 the southwest monsoon withdrew from the whole country and the northeast monsoon began on 15 October.
• IMD's own coupled model: Monsoon Mission Coupled Forecast System (MMCFS); MME-based forecasting since 2021.
• Positive IOD threshold cited by IMD: +0.4 °C.
• IMD functions under the Ministry of Earth Sciences.

One-liners for SSC, Banking and Railways

• IMD released its November 2026 rainfall and temperature outlook on 31 October 2026.
• The northeast monsoon season runs from October to December.
• The Indian state that gets nearly half its annual rain from the northeast monsoon: Tamil Nadu.
• LPA in IMD forecasts stands for Long Period Average.
• Ocean-atmosphere phenomenon in the Pacific cited by IMD for November 2026: very strong El Niño.
• Below-normal winter rain can hurt rabi crops through low soil moisture.

Mains practice question

Q. "The northeast monsoon is small in all-India terms but decisive for South Peninsular India." Discuss, with reference to IMD's outlook for November 2026 and the role of ENSO and the Indian Ocean Dipole. (250 words, GS I/GS III)

Points to cover:

1. Mechanism and regions of the northeast monsoon; Tamil Nadu's ~48% share of annual rain.
2. IMD's forecasts: OND "normal" (30 Sep) and November "below normal, <77% of LPA" (31 Oct); LPA and tercile categories.
3. How El Niño and the IOD influence the season, and the limits of seasonal prediction (MJO, easterly disturbances).
4. Impacts on rabi sowing, reservoirs and groundwater, and the role of IMD's extended-range and impact-based forecasts.