Forecast models from sources including the National Weather Service and private providers indicate Seattle's September 20 high will likely reach 68–70°F under partly sunny skies with patchy morning fog and light northerly winds. This setup favors modest daytime heating near the 1991–2020 average of 69.2°F, as marine-layer moisture and increasing cloud cover limit solar radiation while onshore flow moderates peaks. The near-even market split between the 68–69°F and 70–71°F bins reflects model spread on exact timing of clearing and wind strength, with historical September variability showing highs routinely fluctuating 3–5°F around the mean under similar high-pressure patterns. Updated National Weather Service guidance and afternoon observations will determine final resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Seattle on September 20?
Highest temperature in Seattle on September 20?
68-69°F 29%
70-71°F 28%
66-67°F 14%
72-73°F 13%
NEW
NEW
Sep 20, 2026
63°F or below
1%
64-65°F
6%
66-67°F
14%
68-69°F
29%
70-71°F
28%
72-73°F
13%
74-75°F
6%
76-77°F
3%
78-79°F
1%
80-81°F
<1%
82°F or higher
<1%
68-69°F 29%
70-71°F 28%
66-67°F 14%
72-73°F 13%
NEW
NEW
Sep 20, 2026
63°F or below
$434 Vol.
1%
64-65°F
$337 Vol.
6%
66-67°F
$93 Vol.
14%
68-69°F
$260 Vol.
29%
70-71°F
$272 Vol.
28%
72-73°F
$82 Vol.
13%
74-75°F
$303 Vol.
6%
76-77°F
$100 Vol.
3%
78-79°F
$131 Vol.
1%
80-81°F
$135 Vol.
<1%
82°F or higher
$125 Vol.
<1%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksea
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.Forecast models from sources including the National Weather Service and private providers indicate Seattle's September 20 high will likely reach 68–70°F under partly sunny skies with patchy morning fog and light northerly winds. This setup favors modest daytime heating near the 1991–2020 average of 69.2°F, as marine-layer moisture and increasing cloud cover limit solar radiation while onshore flow moderates peaks. The near-even market split between the 68–69°F and 70–71°F bins reflects model spread on exact timing of clearing and wind strength, with historical September variability showing highs routinely fluctuating 3–5°F around the mean under similar high-pressure patterns. Updated National Weather Service guidance and afternoon observations will determine final resolution.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksea
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksea
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Market Opened: Sep 18, 2026, 7:55 AM ET
Volume
$2,273End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 7:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kseaResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksea
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.Forecast models from sources including the National Weather Service and private providers indicate Seattle's September 20 high will likely reach 68–70°F under partly sunny skies with patchy morning fog and light northerly winds. This setup favors modest daytime heating near the 1991–2020 average of 69.2°F, as marine-layer moisture and increasing cloud cover limit solar radiation while onshore flow moderates peaks. The near-even market split between the 68–69°F and 70–71°F bins reflects model spread on exact timing of clearing and wind strength, with historical September variability showing highs routinely fluctuating 3–5°F around the mean under similar high-pressure patterns. Updated National Weather Service guidance and afternoon observations will determine final resolution.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksea
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksea
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Volume
$2,273End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 7:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kseaResolver
0x69c47De9D...Forecast models from sources including the National Weather Service and private providers indicate Seattle's September 20 high will likely reach 68–70°F under partly sunny skies with patchy morning fog and light northerly winds. This setup favors modest daytime heating near the 1991–2020 average of 69.2°F, as marine-layer moisture and increasing cloud cover limit solar radiation while onshore flow moderates peaks. The near-even market split between the 68–69°F and 70–71°F bins reflects model spread on exact timing of clearing and wind strength, with historical September variability showing highs routinely fluctuating 3–5°F around the mean under similar high-pressure patterns. Updated National Weather Service guidance and afternoon observations will determine final resolution.
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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