El Niño surges back—and drought and floods are colliding with markets’ biggest risk: power and food shocks

El Niño is returning and is already tracking toward the strongest and most severe event on record, with NOAA indicating a 69% chance that the October–December period will bring a “historic” El Niño. Multiple outlets frame this as a global weather disruptor that will “wreak havoc” across regions, not just in the tropics. In Europe, Italy is described as split by weather: heavy rains are expected in the north around Thursday and Friday, followed by sunnier conditions over the weekend but continued instability in the north. In the United States, severe drought is pushing two major reservoirs to historic lows, raising risks to electricity supply for millions, while seven states that depend on the Colorado River face heightened stress. Geopolitically, the cluster points to climate-driven pressure on critical infrastructure and cross-border supply chains rather than direct military confrontation. El Niño typically reshapes rainfall, temperature, and storm tracks, which can intensify water scarcity in some basins while increasing flood and runoff risk in others, creating political friction over resource allocation. Italy’s north–south weather divergence highlights how internal regional vulnerabilities can widen—especially where agriculture, hydropower, and transport are sensitive to short, extreme events. In the US Southwest, reservoir depletion and power-supply risk can translate into regulatory and fiscal responses, while also increasing the likelihood of emergency measures that strain inter-state water governance. The market implications are most immediate in power, water, and climate-sensitive commodities. Drought and reservoir drawdowns can lift electricity risk premia and increase the probability of higher wholesale prices, especially where hydropower and thermal generation compete under water constraints; the US reservoir story implies direct supply risk for millions. Flood-prone conditions in Italy’s north can disrupt logistics and raise near-term costs for agriculture and construction, while also affecting insurance and reinsurance pricing for weather-related claims. El Niño’s “historic” framing increases the probability of broader commodity volatility into late 2026 and 2027, with investors likely to watch energy (power and gas burn), soft commodities, and agricultural inputs as weather uncertainty widens. Next, the key watch items are the NOAA probability updates for the October–December window and any follow-on guidance on expected impacts into 2027. For Italy, triggers include the timing and intensity of the “worst rain” window and whether instability persists into the weekend, which would affect flood risk management and transport recovery. For the US, the decisive indicators are reservoir levels versus operational minimums, Colorado River flow forecasts, and grid reliability assessments tied to water availability. A practical escalation/de-escalation timeline is: near-term (days) for Italy’s rainfall and US reservoir/flow updates, then medium-term (weeks) for El Niño strength confirmation and power-market positioning, with late-2026 to early-2027 as the window where “historic” impacts could broaden into wider commodity and inflation channels.

Geopolitical Implications

• 01

  Climate shocks are pressuring water and power systems, increasing policy and fiscal stress.

• 02

  Colorado River dependence raises the stakes for inter-state water governance and emergency measures.

• 03

  Italy’s north-south weather split can widen internal vulnerability and preparedness gaps.

• 04

  Global El Niño impacts raise the risk of synchronized food and energy disruptions, feeding inflation trade-offs.

Key Signals

• —NOAA updates to El Niño odds and strength guidance for Oct–Dec.
• —US reservoir levels vs operational minimums and any grid reliability advisories.
• —Colorado River flow forecasts and signals of allocation shortfalls.
• —Italy rainfall totals, flood alerts, and whether instability persists beyond the weekend.