**Trader sentiment for a peak RONI above 2.5°C (68.5% implied probability) is driven primarily by NOAA CPC’s August 13 outlook assigning a 69% chance of a historic October–December 2026 RONI value exceeding all prior events since 1950, alongside >90% odds of a very strong peak (≥+2.0°C).** Current conditions support this positioning: the event has strengthened rapidly since spring 2026, with July Niño-3.4 anomalies at +1.4°C (conventional) and RONI near +1.0°C for MJJ, weekly Niño-3.4 reaching +2.6°C by late August, and coupled ocean-atmosphere signals including deep subsurface warming (+10°C anomalies) and westerly wind anomalies. Multi-model ensembles (CFSv2, GFDL SPEAR, IRI) converge on an Oct–Dec peak amid record or near-record Niño-3.4 warmth, with the relative index isolating ENSO strength from background tropical warming. Lower-probability bins (2.0–2.5 at 29% combined) reflect remaining ensemble spread and typical late-season forecast adjustments before the peak window closes.
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 69%
2.25–2.5 21%
2.0–2.25 7.8%
1.5–2.0 <1%
$15,791 Vol.
$15,791 Vol.
Mar 31, 2027
Under 1.5
<1%
1.5–2.0
1%
2.0–2.25
8%
2.25–2.5
21%
Over 2.5
69%
Over 2.5 69%
2.25–2.5 21%
2.0–2.25 7.8%
1.5–2.0 <1%
$15,791 Vol.
$15,791 Vol.
Mar 31, 2027
Under 1.5
$801 Vol.
<1%
1.5–2.0
$1,345 Vol.
1%
2.0–2.25
$1,909 Vol.
8%
2.25–2.5
$4,319 Vol.
21%
Over 2.5
$7,417 Vol.
69%
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.**Trader sentiment for a peak RONI above 2.5°C (68.5% implied probability) is driven primarily by NOAA CPC’s August 13 outlook assigning a 69% chance of a historic October–December 2026 RONI value exceeding all prior events since 1950, alongside >90% odds of a very strong peak (≥+2.0°C).**
Current conditions support this positioning: the event has strengthened rapidly since spring 2026, with July Niño-3.4 anomalies at +1.4°C (conventional) and RONI near +1.0°C for MJJ, weekly Niño-3.4 reaching +2.6°C by late August, and coupled ocean-atmosphere signals including deep subsurface warming (+10°C anomalies) and westerly wind anomalies. Multi-model ensembles (CFSv2, GFDL SPEAR, IRI) converge on an Oct–Dec peak amid record or near-record Niño-3.4 warmth, with the relative index isolating ENSO strength from background tropical warming.
Lower-probability bins (2.0–2.5 at 29% combined) reflect remaining ensemble spread and typical late-season forecast adjustments before the peak window closes.
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
$15,791End 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.**Trader sentiment for a peak RONI above 2.5°C (68.5% implied probability) is driven primarily by NOAA CPC’s August 13 outlook assigning a 69% chance of a historic October–December 2026 RONI value exceeding all prior events since 1950, alongside >90% odds of a very strong peak (≥+2.0°C).**
Current conditions support this positioning: the event has strengthened rapidly since spring 2026, with July Niño-3.4 anomalies at +1.4°C (conventional) and RONI near +1.0°C for MJJ, weekly Niño-3.4 reaching +2.6°C by late August, and coupled ocean-atmosphere signals including deep subsurface warming (+10°C anomalies) and westerly wind anomalies. Multi-model ensembles (CFSv2, GFDL SPEAR, IRI) converge on an Oct–Dec peak amid record or near-record Niño-3.4 warmth, with the relative index isolating ENSO strength from background tropical warming.
Lower-probability bins (2.0–2.5 at 29% combined) reflect remaining ensemble spread and typical late-season forecast adjustments before the peak window closes.
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
$15,791End Date
Apr 1, 2027Market Opened
Aug 17, 2026, 3:17 PM ETResolver
0x69c47De9D...**Trader sentiment for a peak RONI above 2.5°C (68.5% implied probability) is driven primarily by NOAA CPC’s August 13 outlook assigning a 69% chance of a historic October–December 2026 RONI value exceeding all prior events since 1950, alongside >90% odds of a very strong peak (≥+2.0°C).** Current conditions support this positioning: the event has strengthened rapidly since spring 2026, with July Niño-3.4 anomalies at +1.4°C (conventional) and RONI near +1.0°C for MJJ, weekly Niño-3.4 reaching +2.6°C by late August, and coupled ocean-atmosphere signals including deep subsurface warming (+10°C anomalies) and westerly wind anomalies. Multi-model ensembles (CFSv2, GFDL SPEAR, IRI) converge on an Oct–Dec peak amid record or near-record Niño-3.4 warmth, with the relative index isolating ENSO strength from background tropical warming. Lower-probability bins (2.0–2.5 at 29% combined) reflect remaining ensemble spread and typical late-season forecast adjustments before the peak window closes.
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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