Recent NOAA CPC and multi-model ensemble forecasts position the 2026–27 El Niño for a very strong peak, with sea surface temperature anomalies in the Niño-3.4 region already exceeding +2.0°C in parts of the eastern Pacific and RONI values reaching +1.0–1.3°C in recent months. The Relative Oceanic Niño Index (RONI), which isolates the ENSO signal by subtracting tropical-mean anomalies and rescaling variance, underpins the market's focus. Official outlooks assign over 90% probability to a very strong event (≥2.0°C) during fall and winter 2026–27, with 69% odds of a historic peak exceeding +2.5°C on the three-month RONI during October–December, aligning closely with the 63% market-implied probability for Over 2.5. Strengthening subsurface warmth, atmospheric coupling, and consistent model runs from IRI and others support this trajectory, though forecast spread introduces modest uncertainty around exact magnitude.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedWhat will the peak RONI be for the 2026–27 El Niño?
What will the peak RONI be for the 2026–27 El Niño?
Over 2.5 63%
2.25–2.5 20%
2.0–2.25 14.2%
1.5–2.0 2.6%
NEW
NEW
Mar 31, 2027
Under 1.5
<1%
1.5–2.0
3%
2.0–2.25
14%
2.25–2.5
20%
Over 2.5
63%
Over 2.5 63%
2.25–2.5 20%
2.0–2.25 14.2%
1.5–2.0 2.6%
NEW
NEW
Mar 31, 2027
Under 1.5
$518 Vol.
<1%
1.5–2.0
$664 Vol.
3%
2.0–2.25
$1,256 Vol.
14%
2.25–2.5
$1,777 Vol.
20%
Over 2.5
$2,602 Vol.
63%
This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is below +1.5°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is at least +1.5°C and below +2.0°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is at least +2.0°C and below +2.25°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is at least +2.25°C and below +2.5°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is +2.5°C or above. Otherwise, it resolves "No". This market resolves "Yes" as soon as NOAA publishes a RONI value of +2.5°C or above for any listed season. If no listed season reaches +2.5°C, this market resolves "No" once NOAA has published the RONI value for DJF 2026-27.
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.Recent NOAA CPC and multi-model ensemble forecasts position the 2026–27 El Niño for a very strong peak, with sea surface temperature anomalies in the Niño-3.4 region already exceeding +2.0°C in parts of the eastern Pacific and RONI values reaching +1.0–1.3°C in recent months. The Relative Oceanic Niño Index (RONI), which isolates the ENSO signal by subtracting tropical-mean anomalies and rescaling variance, underpins the market's focus. Official outlooks assign over 90% probability to a very strong event (≥2.0°C) during fall and winter 2026–27, with 69% odds of a historic peak exceeding +2.5°C on the three-month RONI during October–December, aligning closely with the 63% market-implied probability for Over 2.5. Strengthening subsurface warmth, atmospheric coupling, and consistent model runs from IRI and others support this trajectory, though forecast spread introduces modest uncertainty around exact magnitude.
This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is below +1.5°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.
Market Opened: Aug 17, 2026, 3:17 PM ET
Volume
$6,817End Date
Apr 1, 2027Market Opened
Aug 17, 2026, 3:17 PM ETResolver
0x69c47De9D...This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is below +1.5°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is at least +1.5°C and below +2.0°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is at least +2.0°C and below +2.25°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is at least +2.25°C and below +2.5°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is +2.5°C or above. Otherwise, it resolves "No". This market resolves "Yes" as soon as NOAA publishes a RONI value of +2.5°C or above for any listed season. If no listed season reaches +2.5°C, this market resolves "No" once NOAA has published the RONI value for DJF 2026-27.
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.Recent NOAA CPC and multi-model ensemble forecasts position the 2026–27 El Niño for a very strong peak, with sea surface temperature anomalies in the Niño-3.4 region already exceeding +2.0°C in parts of the eastern Pacific and RONI values reaching +1.0–1.3°C in recent months. The Relative Oceanic Niño Index (RONI), which isolates the ENSO signal by subtracting tropical-mean anomalies and rescaling variance, underpins the market's focus. Official outlooks assign over 90% probability to a very strong event (≥2.0°C) during fall and winter 2026–27, with 69% odds of a historic peak exceeding +2.5°C on the three-month RONI during October–December, aligning closely with the 63% market-implied probability for Over 2.5. Strengthening subsurface warmth, atmospheric coupling, and consistent model runs from IRI and others support this trajectory, though forecast spread introduces modest uncertainty around exact magnitude.
This market resolves "Yes" if the peak RONI for the 2026–27 El Niño is below +1.5°C. Otherwise, it resolves "No".
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.
The peak RONI is the single highest Regional Ocean Niño Index (RONI) value reported by NOAA's Climate Prediction Center (CPC) across the overlapping three-month seasons ASO 2026, SON 2026, OND 2026, NDJ 2026-27, and DJF 2026-27, as reported in official NOAA CPC RONI updates (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/).
The first published RONI value for each listed season is final and governs resolution; no subsequent revision to a season's value will change the outcome once that season's first value has been published. If CPC's RONI dataset is permanently discontinued, other information from NOAA may be used.
Volume
$6,817End Date
Apr 1, 2027Market Opened
Aug 17, 2026, 3:17 PM ETResolver
0x69c47De9D...Recent NOAA CPC and multi-model ensemble forecasts position the 2026–27 El Niño for a very strong peak, with sea surface temperature anomalies in the Niño-3.4 region already exceeding +2.0°C in parts of the eastern Pacific and RONI values reaching +1.0–1.3°C in recent months. The Relative Oceanic Niño Index (RONI), which isolates the ENSO signal by subtracting tropical-mean anomalies and rescaling variance, underpins the market's focus. Official outlooks assign over 90% probability to a very strong event (≥2.0°C) during fall and winter 2026–27, with 69% odds of a historic peak exceeding +2.5°C on the three-month RONI during October–December, aligning closely with the 63% market-implied probability for Over 2.5. Strengthening subsurface warmth, atmospheric coupling, and consistent model runs from IRI and others support this trajectory, though forecast spread introduces modest uncertainty around exact magnitude.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
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