Strong El Niño conditions, now classified as very strong with Niño 3.4 anomalies exceeding +2.5 °C and still intensifying, represent the dominant near-term driver elevating September 2026 global temperatures above the September 2023 record of +0.93 °C anomaly. Early-month observations combined with ECMWF ensemble forecasts project a September mean near 16.45 °C, sufficient for a narrow lead over prior Septembers while remaining well below the all-time monthly peak set by July 2023. Persistent ocean heat content anomalies, including a recent daily global sea-surface temperature record, reinforce this trajectory amid the lagged warming influence of the developing El Niño. Forecast ranges still carry notable spread due to potential model divergence and late-month variability, keeping a clear but not overwhelming market-implied edge for first or second place among recorded Septembers.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedSeptember 2026 1st, 2nd, or 3rd hottest on record?
September 2026 1st, 2nd, or 3rd hottest on record?
2nd hottest 82%
1st hottest 42%
4th or lower 19%
3rd hottest 12%
NEW
NEW
Sep 30, 2026
1st hottest
42%
2nd hottest
61%
3rd hottest
12%
4th or lower
19%
2nd hottest 82%
1st hottest 42%
4th or lower 19%
3rd hottest 12%
NEW
NEW
Sep 30, 2026
1st hottest
$289 Vol.
42%
2nd hottest
$1 Vol.
61%
3rd hottest
$190 Vol.
12%
4th or lower
$250 Vol.
19%
This market will resolve based on the data for the Global Land-Ocean Temperature Index for September 2026 versus the data points available for all other Septembers on record.
Note: If September 2026 is tied for first, second, or third hottest with another year, it will qualify for the bracket it ties with.
The primary resolution source for this market will be the figures found in the table titled "GLOBAL Land-Ocean Temperature Index in 0.01 degrees Celsius" under the column for the relevant month (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt). If NASA's "Global Temperature Index" is rendered permanently unavailable, other information from NASA may be used.
If no information for September 2026 is provided by NASA by the last day of the following month, 11:59:59 PM ET, a consensus of credible sources will be used to resolve this market.Strong El Niño conditions, now classified as very strong with Niño 3.4 anomalies exceeding +2.5 °C and still intensifying, represent the dominant near-term driver elevating September 2026 global temperatures above the September 2023 record of +0.93 °C anomaly. Early-month observations combined with ECMWF ensemble forecasts project a September mean near 16.45 °C, sufficient for a narrow lead over prior Septembers while remaining well below the all-time monthly peak set by July 2023. Persistent ocean heat content anomalies, including a recent daily global sea-surface temperature record, reinforce this trajectory amid the lagged warming influence of the developing El Niño. Forecast ranges still carry notable spread due to potential model divergence and late-month variability, keeping a clear but not overwhelming market-implied edge for first or second place among recorded Septembers.
This market will resolve based on the data for the Global Land-Ocean Temperature Index for September 2026 versus the data points available for all other Septembers on record.
Note: If September 2026 is tied for first, second, or third hottest with another year, it will qualify for the bracket it ties with.
The primary resolution source for this market will be the figures found in the table titled "GLOBAL Land-Ocean Temperature Index in 0.01 degrees Celsius" under the column for the relevant month (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt). If NASA's "Global Temperature Index" is rendered permanently unavailable, other information from NASA may be used.
If no information for September 2026 is provided by NASA by the last day of the following month, 11:59:59 PM ET, a consensus of credible sources will be used to resolve this market.
Note: If September 2026 is tied for first, second, or third hottest with another year, it will qualify for the bracket it ties with.
The primary resolution source for this market will be the figures found in the table titled "GLOBAL Land-Ocean Temperature Index in 0.01 degrees Celsius" under the column for the relevant month (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt). If NASA's "Global Temperature Index" is rendered permanently unavailable, other information from NASA may be used.
If no information for September 2026 is provided by NASA by the last day of the following month, 11:59:59 PM ET, a consensus of credible sources will be used to resolve this market.
Market Opened: Aug 28, 2026, 11:14 AM ET
Volume
$730End Date
Oct 1, 2026Market Opened
Aug 28, 2026, 11:14 AM ETResolver
0x69c47De9D...This market will resolve based on the data for the Global Land-Ocean Temperature Index for September 2026 versus the data points available for all other Septembers on record.
Note: If September 2026 is tied for first, second, or third hottest with another year, it will qualify for the bracket it ties with.
The primary resolution source for this market will be the figures found in the table titled "GLOBAL Land-Ocean Temperature Index in 0.01 degrees Celsius" under the column for the relevant month (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt). If NASA's "Global Temperature Index" is rendered permanently unavailable, other information from NASA may be used.
If no information for September 2026 is provided by NASA by the last day of the following month, 11:59:59 PM ET, a consensus of credible sources will be used to resolve this market.Strong El Niño conditions, now classified as very strong with Niño 3.4 anomalies exceeding +2.5 °C and still intensifying, represent the dominant near-term driver elevating September 2026 global temperatures above the September 2023 record of +0.93 °C anomaly. Early-month observations combined with ECMWF ensemble forecasts project a September mean near 16.45 °C, sufficient for a narrow lead over prior Septembers while remaining well below the all-time monthly peak set by July 2023. Persistent ocean heat content anomalies, including a recent daily global sea-surface temperature record, reinforce this trajectory amid the lagged warming influence of the developing El Niño. Forecast ranges still carry notable spread due to potential model divergence and late-month variability, keeping a clear but not overwhelming market-implied edge for first or second place among recorded Septembers.
This market will resolve based on the data for the Global Land-Ocean Temperature Index for September 2026 versus the data points available for all other Septembers on record.
Note: If September 2026 is tied for first, second, or third hottest with another year, it will qualify for the bracket it ties with.
The primary resolution source for this market will be the figures found in the table titled "GLOBAL Land-Ocean Temperature Index in 0.01 degrees Celsius" under the column for the relevant month (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt). If NASA's "Global Temperature Index" is rendered permanently unavailable, other information from NASA may be used.
If no information for September 2026 is provided by NASA by the last day of the following month, 11:59:59 PM ET, a consensus of credible sources will be used to resolve this market.
Note: If September 2026 is tied for first, second, or third hottest with another year, it will qualify for the bracket it ties with.
The primary resolution source for this market will be the figures found in the table titled "GLOBAL Land-Ocean Temperature Index in 0.01 degrees Celsius" under the column for the relevant month (https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt). If NASA's "Global Temperature Index" is rendered permanently unavailable, other information from NASA may be used.
If no information for September 2026 is provided by NASA by the last day of the following month, 11:59:59 PM ET, a consensus of credible sources will be used to resolve this market.
Volume
$730End Date
Oct 1, 2026Market Opened
Aug 28, 2026, 11:14 AM ETResolver
0x69c47De9D...Strong El Niño conditions, now classified as very strong with Niño 3.4 anomalies exceeding +2.5 °C and still intensifying, represent the dominant near-term driver elevating September 2026 global temperatures above the September 2023 record of +0.93 °C anomaly. Early-month observations combined with ECMWF ensemble forecasts project a September mean near 16.45 °C, sufficient for a narrow lead over prior Septembers while remaining well below the all-time monthly peak set by July 2023. Persistent ocean heat content anomalies, including a recent daily global sea-surface temperature record, reinforce this trajectory amid the lagged warming influence of the developing El Niño. Forecast ranges still carry notable spread due to potential model divergence and late-month variability, keeping a clear but not overwhelming market-implied edge for first or second place among recorded Septembers.
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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