Recent National Weather Service forecasts and short-range model consensus point to a high of 70–72°F in Seattle on September 18 under mostly clear to partly cloudy skies, driving the clustered market probabilities around those ranges. Southerly flow and high pressure support modest warming, yet limited afternoon mixing and potential marine influence keep peaks from climbing higher, while any earlier cloud development could cap readings near 68–69°F. Historical September climatology shows typical highs near 70°F, but small differences in insolation timing and boundary-layer winds create the narrow spread across leading outcomes. Updated model runs and official briefings ahead of the date remain key variables for traders.
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 18?
Highest temperature in Seattle on September 18?
72-73°F 26%
70-71°F 26%
68-69°F 25%
74-75°F 10%
NEW
NEW
Sep 18, 2026
63°F or below
5%
64-65°F
6%
66-67°F
6%
68-69°F
25%
70-71°F
26%
72-73°F
26%
74-75°F
10%
76-77°F
6%
78-79°F
7%
80-81°F
5%
82°F or higher
5%
72-73°F 26%
70-71°F 26%
68-69°F 25%
74-75°F 10%
NEW
NEW
Sep 18, 2026
63°F or below
$10 Vol.
5%
64-65°F
$10 Vol.
6%
66-67°F
$0 Vol.
6%
68-69°F
$34 Vol.
25%
70-71°F
$0 Vol.
26%
72-73°F
$0 Vol.
26%
74-75°F
$0 Vol.
10%
76-77°F
$0 Vol.
6%
78-79°F
$10 Vol.
7%
80-81°F
$10 Vol.
5%
82°F or higher
$10 Vol.
5%
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 18 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.Recent National Weather Service forecasts and short-range model consensus point to a high of 70–72°F in Seattle on September 18 under mostly clear to partly cloudy skies, driving the clustered market probabilities around those ranges. Southerly flow and high pressure support modest warming, yet limited afternoon mixing and potential marine influence keep peaks from climbing higher, while any earlier cloud development could cap readings near 68–69°F. Historical September climatology shows typical highs near 70°F, but small differences in insolation timing and boundary-layer winds create the narrow spread across leading outcomes. Updated model runs and official briefings ahead of the date remain key variables for traders.
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 18 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 16, 2026, 7:55 AM ET
Volume
$84End Date
Sep 18, 2026Market Opened
Sep 16, 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 18 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.Recent National Weather Service forecasts and short-range model consensus point to a high of 70–72°F in Seattle on September 18 under mostly clear to partly cloudy skies, driving the clustered market probabilities around those ranges. Southerly flow and high pressure support modest warming, yet limited afternoon mixing and potential marine influence keep peaks from climbing higher, while any earlier cloud development could cap readings near 68–69°F. Historical September climatology shows typical highs near 70°F, but small differences in insolation timing and boundary-layer winds create the narrow spread across leading outcomes. Updated model runs and official briefings ahead of the date remain key variables for traders.
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 18 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
$84End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 7:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=kseaResolver
0x69c47De9D...Recent National Weather Service forecasts and short-range model consensus point to a high of 70–72°F in Seattle on September 18 under mostly clear to partly cloudy skies, driving the clustered market probabilities around those ranges. Southerly flow and high pressure support modest warming, yet limited afternoon mixing and potential marine influence keep peaks from climbing higher, while any earlier cloud development could cap readings near 68–69°F. Historical September climatology shows typical highs near 70°F, but small differences in insolation timing and boundary-layer winds create the narrow spread across leading outcomes. Updated model runs and official briefings ahead of the date remain key variables for traders.
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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