A rapidly intensifying strong El Niño, with Niño 3.4 sea surface temperature anomalies already exceeding +2.0–2.7°C in August 2026 and multi-model forecasts pointing toward a possible record peak near +3.5–4.0°C later in the year, represents the main driver pushing September 2026 toward top-tier warmth. This builds on the long-term anthropogenic warming trend and follows a July 2026 that ranked as the joint-second warmest July on record in multiple datasets. The El Niño’s lagged influence on global temperatures creates substantial uncertainty around exact September rankings, as internal variability, model spread in peak timing and strength, and comparisons to prior El Niño-influenced Septembers (notably 2023) can shift outcomes between 1st–3rd hottest or lower. Updated seasonal forecasts from NOAA, WMO, and ECMWF ensembles expected in coming weeks will refine these probabilities.
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?
1st hottest 49%
2nd hottest 49%
3rd hottest 49%
4th or lower 49%
NEW
NEW
Sep 30, 2026
1st hottest
49%
2nd hottest
49%
3rd hottest
49%
4th or lower
49%
1st hottest 49%
2nd hottest 49%
3rd hottest 49%
4th or lower 49%
NEW
NEW
Sep 30, 2026
1st hottest
$0 Vol.
49%
2nd hottest
$0 Vol.
49%
3rd hottest
$0 Vol.
49%
4th or lower
$0 Vol.
49%
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.A rapidly intensifying strong El Niño, with Niño 3.4 sea surface temperature anomalies already exceeding +2.0–2.7°C in August 2026 and multi-model forecasts pointing toward a possible record peak near +3.5–4.0°C later in the year, represents the main driver pushing September 2026 toward top-tier warmth. This builds on the long-term anthropogenic warming trend and follows a July 2026 that ranked as the joint-second warmest July on record in multiple datasets. The El Niño’s lagged influence on global temperatures creates substantial uncertainty around exact September rankings, as internal variability, model spread in peak timing and strength, and comparisons to prior El Niño-influenced Septembers (notably 2023) can shift outcomes between 1st–3rd hottest or lower. Updated seasonal forecasts from NOAA, WMO, and ECMWF ensembles expected in coming weeks will refine these probabilities.
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
$0End 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.A rapidly intensifying strong El Niño, with Niño 3.4 sea surface temperature anomalies already exceeding +2.0–2.7°C in August 2026 and multi-model forecasts pointing toward a possible record peak near +3.5–4.0°C later in the year, represents the main driver pushing September 2026 toward top-tier warmth. This builds on the long-term anthropogenic warming trend and follows a July 2026 that ranked as the joint-second warmest July on record in multiple datasets. The El Niño’s lagged influence on global temperatures creates substantial uncertainty around exact September rankings, as internal variability, model spread in peak timing and strength, and comparisons to prior El Niño-influenced Septembers (notably 2023) can shift outcomes between 1st–3rd hottest or lower. Updated seasonal forecasts from NOAA, WMO, and ECMWF ensembles expected in coming weeks will refine these probabilities.
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
$0End Date
Oct 1, 2026Market Opened
Aug 28, 2026, 11:14 AM ETResolver
0x69c47De9D...A rapidly intensifying strong El Niño, with Niño 3.4 sea surface temperature anomalies already exceeding +2.0–2.7°C in August 2026 and multi-model forecasts pointing toward a possible record peak near +3.5–4.0°C later in the year, represents the main driver pushing September 2026 toward top-tier warmth. This builds on the long-term anthropogenic warming trend and follows a July 2026 that ranked as the joint-second warmest July on record in multiple datasets. The El Niño’s lagged influence on global temperatures creates substantial uncertainty around exact September rankings, as internal variability, model spread in peak timing and strength, and comparisons to prior El Niño-influenced Septembers (notably 2023) can shift outcomes between 1st–3rd hottest or lower. Updated seasonal forecasts from NOAA, WMO, and ECMWF ensembles expected in coming weeks will refine these probabilities.
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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