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icon for What will the peak RONI be for the 2026–27 El Niño?

What will the peak RONI be for the 2026–27 El Niño?

icon for What 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 78%

2.25–2.5 20%

2.0–2.25 2.7%

1.5–2.0 <1%

Polymarket

$49,933 Vol.

Over 2.5 78%

2.25–2.5 20%

2.0–2.25 2.7%

1.5–2.0 <1%

Polymarket

$49,933 Vol.

Under 1.5

$821 Vol.

<1%

1.5–2.0

$2,651 Vol.

1%

2.0–2.25

$3,278 Vol.

3%

2.25–2.5

$19,798 Vol.

20%

Over 2.5

$23,385 Vol.

78%

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 Relative Oceanic 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 Relative Oceanic 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 Relative Oceanic 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 Relative Oceanic 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 Relative Oceanic 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.Rapid intensification of the 2026–27 El Niño, with weekly Niño 3.4 anomalies reaching +3.0°C by mid-September and RONI at +1.4°C for JJA, underpins trader consensus for a peak RONI above 2.5. NOAA’s September 10 outlook assigns over 90% probability of a very strong event (≥+2.0°C) and 75% odds of a historic peak exceeding all post-1950 records on the three-month RONI during October–December, driven by record subsurface heat content rivaling 1997–98 and model ensembles projecting seasonal peaks near +3.6°C. All dynamical models align on further strengthening through the typical winter maximum, with limited downside risk from current atmospheric coupling. Updated CPC and IRI forecasts in coming weeks will refine these market-implied odds.

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 Relative Oceanic 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 below +1.5°C. Otherwise, it resolves "No". The peak RONI is the single highest Relative Oceanic 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
$49,933
End Date
Apr 1, 2027
Market Opened
Aug 17, 2026, 3:17 PM ET

Resolution Source

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/

Resolver

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 Relative Oceanic 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 Relative Oceanic 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 Relative Oceanic 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 Relative Oceanic 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 Relative Oceanic 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.Rapid intensification of the 2026–27 El Niño, with weekly Niño 3.4 anomalies reaching +3.0°C by mid-September and RONI at +1.4°C for JJA, underpins trader consensus for a peak RONI above 2.5. NOAA’s September 10 outlook assigns over 90% probability of a very strong event (≥+2.0°C) and 75% odds of a historic peak exceeding all post-1950 records on the three-month RONI during October–December, driven by record subsurface heat content rivaling 1997–98 and model ensembles projecting seasonal peaks near +3.6°C. All dynamical models align on further strengthening through the typical winter maximum, with limited downside risk from current atmospheric coupling. Updated CPC and IRI forecasts in coming weeks will refine these market-implied odds.

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 Relative Oceanic 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 below +1.5°C. Otherwise, it resolves "No". The peak RONI is the single highest Relative Oceanic 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
$49,933
End Date
Apr 1, 2027
Market Opened
Aug 17, 2026, 3:17 PM ET

Resolution Source

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/

Resolver

0x69c47De9D...

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Frequently Asked Questions

"What will the peak RONI be for the 2026–27 El Niño?" is a prediction market on Polymarket with 5 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "Over 2.5" at 78%, followed by "2.25–2.5" at 20%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 78¢ implies that the market collectively assigns a 78% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

As of today, "What will the peak RONI be for the 2026–27 El Niño?" has generated $49.9K in total trading volume since the market launched on Aug 17, 2026. This level of trading activity reflects strong engagement from the Polymarket community and helps ensure that the current odds are informed by a deep pool of market participants. You can track live price movements and trade on any outcome directly on this page.

To trade on "What will the peak RONI be for the 2026–27 El Niño?," browse the 5 available outcomes listed on this page. Each outcome displays a current price representing the market's implied probability. To take a position, select the outcome you believe is most likely, choose "Yes" to trade in favor of it or "No" to trade against it, enter your amount, and click "Trade." If your chosen outcome is correct when the market resolves, your "Yes" shares pay out $1 each. If it's incorrect, they pay out $0. You can also sell your shares at any time before resolution if you want to lock in a profit or cut a loss.

The current frontrunner for "What will the peak RONI be for the 2026–27 El Niño?" is "Over 2.5" at 78%, meaning the market assigns a 78% chance to that outcome. The next closest outcome is "2.25–2.5" at 20%. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "What will the peak RONI be for the 2026–27 El Niño?" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.