Rapid Transition from La Niña

The Pacific has undergone a remarkably fast reversal. After a multi-year La Niña that persisted into early 2026, the equatorial Pacific flipped to ENSO-neutral by April and is now rapidly warming into El Niño . Weekly sea surface temperature (SST) anomalies in the key Niño3.4 region have already surged past +0.9°C, well above the El Niño threshold . The U.S. National Weather Service notes that very warm ocean waters continue to build across the equatorial Pacific, making El Niño "all but certain through the end of the year and into next year" .

Probability Assessments from Major Agencies

A strong consensus exists across the world's major meteorological bodies:

• NOAA/CPC (June 12): 82% chance of El Niño in May–July 2026; 96% chance persisting through December 2026 – February 2027 . No single strength category exceeds 37% probability, meaning substantial uncertainty remains on peak intensity .
• IRI/Columbia (June 5): 98% probability of El Niño for May–July 2026 .
• WMO (June 2): Officially announced El Niño conditions are developing, set to influence global temperature and rainfall patterns .
• UK Met Office: Very high likelihood of El Niño developing, with around a 70% chance of a strong or very strong event later in 2026 .
• PAGASA (Philippines, June 10–11): El Niño conditions now present, with over 80% probability of a full-blown event persisting until early 2027 .
• ESPOL (Ecuador): Expects El Niño onset in the trimester centered on June (82% probability), with warm anomalies persisting through December–February .

Sea Surface Temperature Anomaly and Intensity Outlook

Weekly Niño3.4 SST anomalies have reached +0.9°C, though monthly values remain near the borderline threshold . Forecasters say the event has the potential to become one of the most intense on record . Some models project that SST anomalies could exceed +2.0°C in the Niño3.4 region by late 2026, with certain localized areas of the eastern Pacific potentially approaching or exceeding +3.0°C . However, NOAA notes substantial uncertainty in peak strength, with no single strength category exceeding 37% odds, as the final outcome depends on fickle wind patterns and ocean-atmosphere coupling .

Expected Global Consequences

Drought and food security in the Philippines and Southeast Asia: PAGASA has warned that El Niño will bring reduced rainfall, increasing the risk of drought across the Philippines . A Welthungerhilfe briefing (June 10) flags serious implications for agriculture and food security in vulnerable regions .

Altered typhoon patterns in the western Pacific: El Niño typically shifts typhoon activity eastward and can increase the frequency of intense storms in the central and western Pacific, altering the typical tracks that affect East and Southeast Asia .

Increased precipitation and flood risk in California and the Desert Southwest: In the United States, El Niño is associated with a shifted jet stream that drives stormier, wetter conditions across California and the southern tier of the country, raising the risk of flooding and heavy precipitation .

Other global impacts: The WRI (June 3) notes that a Super El Niño brings heightened risks of droughts, floods, cyclones, and extreme heat . The UK Met Office warns that when a strong El Niño develops in today's warmer climate, the impacts are amplified .

Warnings from Global Leaders and Scientists

• World Meteorological Organization (WMO): Issued a global call to prepare, stating that El Niño will "influence global temperature and rainfall patterns, increasing the risk of extreme weather" . The WMO also warned that a record-hot year is highly likely by 2030, with the El Niño potentially breaking global temperature records as early as 2027 .
• BBC (May 14): Reported "growing assurance" this could become one of the most intense El Niño episodes ever recorded, with alerts about "unprecedented global temperatures and significant humanitarian effects" .
• The Guardian (June 11): Described the event as set to "turbocharge extreme weather" globally .
• CNN (June 11): Declared El Niño "officially here" with forecasts pointing to a "Super El Niño" bringing major shifts in global weather and an even hotter climate .
• Phys.org (May 22): Noted scientists say the outcome hinges on "fickle winds and other volatile atmospheric shifts," making it too early to be fully confident in a history-making event .

Key caveat: While the probability of El Niño is extremely high, its ultimate strength remains uncertain. NOAA emphasizes that no intensity category exceeds 37% probability . The transition from a multi-year La Niña to a potential Super El Niño within a single year is exceptionally rapid, and small atmospheric variations could still moderate the outcome.

Rapid Transition from La Niña

The Pacific has undergone a remarkably fast reversal. After a multi-year La Niña that persisted into early 2026, the equatorial Pacific flipped to ENSO-neutral by April and is now rapidly warming into El Niño . Weekly sea surface temperature (SST) anomalies in the key Niño3.4 region have already surged past +0.9°C, well above the El Niño threshold . The U.S. National Weather Service notes that very warm ocean waters continue to build across the equatorial Pacific, making El Niño "all but certain through the end of the year and into next year" .

Probability Assessments from Major Agencies

A strong consensus exists across the world's major meteorological bodies:

• NOAA/CPC (June 12): 82% chance of El Niño in May–July 2026; 96% chance persisting through December 2026 – February 2027 . No single strength category exceeds 37% probability, meaning substantial uncertainty remains on peak intensity .
• IRI/Columbia (June 5): 98% probability of El Niño for May–July 2026 .
• WMO (June 2): Officially announced El Niño conditions are developing, set to influence global temperature and rainfall patterns .
• UK Met Office: Very high likelihood of El Niño developing, with around a 70% chance of a strong or very strong event later in 2026 .
• PAGASA (Philippines, June 10–11): El Niño conditions now present, with over 80% probability of a full-blown event persisting until early 2027 .
• ESPOL (Ecuador): Expects El Niño onset in the trimester centered on June (82% probability), with warm anomalies persisting through December–February .

Sea Surface Temperature Anomaly and Intensity Outlook

Weekly Niño3.4 SST anomalies have reached +0.9°C, though monthly values remain near the borderline threshold . Forecasters say the event has the potential to become one of the most intense on record . Some models project that SST anomalies could exceed +2.0°C in the Niño3.4 region by late 2026, with certain localized areas of the eastern Pacific potentially approaching or exceeding +3.0°C . However, NOAA notes substantial uncertainty in peak strength, with no single strength category exceeding 37% odds, as the final outcome depends on fickle wind patterns and ocean-atmosphere coupling .

Expected Global Consequences

Drought and food security in the Philippines and Southeast Asia: PAGASA has warned that El Niño will bring reduced rainfall, increasing the risk of drought across the Philippines . A Welthungerhilfe briefing (June 10) flags serious implications for agriculture and food security in vulnerable regions .

Altered typhoon patterns in the western Pacific: El Niño typically shifts typhoon activity eastward and can increase the frequency of intense storms in the central and western Pacific, altering the typical tracks that affect East and Southeast Asia .

Increased precipitation and flood risk in California and the Desert Southwest: In the United States, El Niño is associated with a shifted jet stream that drives stormier, wetter conditions across California and the southern tier of the country, raising the risk of flooding and heavy precipitation .

Other global impacts: The WRI (June 3) notes that a Super El Niño brings heightened risks of droughts, floods, cyclones, and extreme heat . The UK Met Office warns that when a strong El Niño develops in today's warmer climate, the impacts are amplified .

Warnings from Global Leaders and Scientists

• World Meteorological Organization (WMO): Issued a global call to prepare, stating that El Niño will "influence global temperature and rainfall patterns, increasing the risk of extreme weather" . The WMO also warned that a record-hot year is highly likely by 2030, with the El Niño potentially breaking global temperature records as early as 2027 .
• BBC (May 14): Reported "growing assurance" this could become one of the most intense El Niño episodes ever recorded, with alerts about "unprecedented global temperatures and significant humanitarian effects" .
• The Guardian (June 11): Described the event as set to "turbocharge extreme weather" globally .
• CNN (June 11): Declared El Niño "officially here" with forecasts pointing to a "Super El Niño" bringing major shifts in global weather and an even hotter climate .
• Phys.org (May 22): Noted scientists say the outcome hinges on "fickle winds and other volatile atmospheric shifts," making it too early to be fully confident in a history-making event .

Key caveat: While the probability of El Niño is extremely high, its ultimate strength remains uncertain. NOAA emphasizes that no intensity category exceeds 37% probability . The transition from a multi-year La Niña to a potential Super El Niño within a single year is exceptionally rapid, and small atmospheric variations could still moderate the outcome.