FAO report flags elevated flood and food security risks as the second inter-monsoon and northeast monsoon seasons coincide with potentially exceptional Pacific warming.

Sri Lanka is set to experience wetter-than-average conditions beginning in October 2026, driven primarily by a strengthening El Niño event that climate agencies warn could rank among the strongest on record and persist into 2027. A recent Food and Agriculture Organization (FAO) assessment on Asia and the Pacific has placed the island among countries of elevated concern, highlighting the potential for intense and widespread rainfall during the second inter-monsoon and the subsequent northeast monsoon.

The timing is critical. October and November typically deliver around 30 per cent of Sri Lanka’s annual rainfall, with precipitation often widespread and locally intense. This period feeds into the northeast monsoon from December to February, which supplies a substantial share of the country’s yearly water. The FAO report notes that the wetter signal becomes particularly important from October onward, coinciding with these key seasons.

Local meteorological authorities have echoed the warning. Director General of the Department of Meteorology Ajith Wijemanna has indicated that rainfall during October and November could exceed seasonal averages, raising the prospect of rapid rises in reservoir levels and localised flooding in low-lying and flood-prone areas. While flooding is not guaranteed, authorities have urged preparedness.

A Potentially Exceptional El Niño Event

Forecasts from the United States Climate Prediction Center (CPC) and other global centres point to a very strong, possibly exceptional, El Niño. Multi-model ensembles suggest sea-surface temperature anomalies could exceed levels seen in the powerful 1997 and 2015 events. There is now more than a 90 per cent probability that current conditions will intensify into a very strong event by the end of 2026, with a substantial chance it will rank among the strongest since at least 1950. The phenomenon is expected to persist well into early 2027.

El Niño arises from unusually warm sea-surface temperatures in the central and eastern equatorial Pacific. These temperature shifts alter atmospheric circulation patterns globally, influencing rainfall and temperature far beyond the Pacific basin. For Sri Lanka, historical analysis by the Department of Meteorology shows that impacts vary by season and by the concurrent state of the Indian Ocean Dipole (IOD).

Role of the Indian Ocean Dipole

The evolution of the IOD will be decisive. A positive IOD phase, if it strengthens, tends to enhance moisture transport over the Indian Ocean and can offset some of the drying influence that strong El Niño events often exert on South Asian rainfall. The FAO report notes that, as with Pakistan, a positive IOD would favour wetter conditions over Sri Lanka. Climate models have indicated a reasonable probability of a positive IOD developing later in 2026, which could help sustain rainfall during the Second Inter-Monsoon.

Without a sufficiently strong or timely positive IOD, however, the Northeast Monsoon period could still present challenges, consistent with Sri Lanka’s experience during previous strong El Niño years. Meteorologists stress that outcomes will depend on the interplay of El Niño, the IOD, the Madden-Julian Oscillation and other regional drivers rather than on any single factor.

Implications for Agriculture and Water Resources

The Second Inter-Monsoon and Northeast Monsoon are central to Sri Lanka’s agricultural calendar, particularly the Maha cultivation season. Above-average rainfall could replenish reservoirs that have been under pressure following drier conditions earlier in the year. Yet excessive or poorly timed rain risks waterlogging, delayed planting, damage to young crops and localized flooding.

The FAO assessment places Sri Lanka among countries of elevated climate and food-system risk. Across monitored countries in Asia and the Pacific, the combined effects of the evolving El Niño and concurrent economic pressures could push an additional 8.2 million people into acute food insecurity, with the true figure likely higher. The “three Fs” – food, fuel and fertiliser – continue to exert cascading pressure. Urea prices more than doubled at their peak, while fuel and food prices remain elevated, raising the risk that any climate-related production losses translate into higher food insecurity in late 2026 and 2027.

Sri Lanka remains exposed to imported fertiliser and international commodity price swings. Diesel and petrol prices have stayed significantly above pre-crisis levels, adding to production costs for farmers already navigating uncertain weather.

Preparedness Window Remains Open

The FAO emphasises that while risks are emerging, widespread impacts have not yet materialised. This creates a narrowing but still critical window for anticipatory action. Humanitarian and development partners have been urged to work closely with the government to strengthen monitoring, early-warning systems, preparedness and response before losses become entrenched. The most serious agricultural and food-security consequences may not fully appear until late 2026 and into 2027.

The Department of Meteorology has already advised authorities and the public to remain vigilant. Reservoir management, drainage maintenance in flood-prone districts, and contingency planning for the Maha season will be essential. Communities in low-lying areas and those dependent on rain-fed agriculture face particular exposure.

Broader Regional Context

The same FAO report and World Meteorological Organisation updates describe a classic strong El Niño footprint across the globe: wetter conditions in some regions, heightened drought risk in others, and widespread above-normal temperatures. For South Asia the picture is mixed and highly dependent on Indian Ocean conditions. Sri Lanka’s island geography and central highlands provide some buffering against extreme moisture depletion, yet the country remains sensitive to shifts in monsoon timing and intensity.

Earlier in 2026, drier and hotter conditions associated with the developing El Niño affected parts of the dry zone and contributed to reduced reservoir inflows. The shift toward a wetter outlook from October therefore represents a significant change in the seasonal risk profile – from water scarcity concerns to flood and excess-moisture risks.

Seasonal Guidance

As September progresses, closer monitoring of both Pacific sea-surface temperatures and the state of the Indian Ocean Dipole will refine the outlook. The Department of Meteorology continues to issue seasonal guidance, and international agencies are tracking the event closely. For Sri Lanka, the coming months will test the resilience of agricultural systems, water infrastructure and disaster-preparedness mechanisms at a time when the economy is still recovering from recent shocks.

Authorities stress that while a wetter-than-average season offers opportunities for reservoir recovery, the intensity and distribution of rainfall will determine whether the outcome is beneficial or disruptive. Proactive measures now – from improved early-warning communication to targeted support for vulnerable farming communities – can substantially reduce the eventual human and economic cost, the FAO report says.