Current forecast guidance from the National Weather Service and other models shows Seattle's August 20 high most likely reaching 79–82°F under partly sunny skies and light onshore flow. Persistent marine air from the Pacific and Puget Sound continues to moderate daytime warming, preventing stronger heating despite seasonal solar input. Ensemble spreads remain modest, with limited model disagreement on cloud cover or wind shifts that could push readings into the mid-80s or hold them in the upper 70s. This distribution aligns with late-August climatology near Sea-Tac, where average highs hover around 77°F and extremes above 85°F are uncommon without offshore flow. Traders have concentrated probability in the 80–83°F range as the latest model runs converge on these values ahead of final observations.
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 August 20?
Highest temperature in Seattle on August 20?
82-83°F 35%
80-81°F 30%
84-85°F 21%
78-79°F 10%
NEW
NEW
Aug 20, 2026
73°F or below
<1%
74-75°F
1%
76-77°F
5%
78-79°F
10%
80-81°F
30%
82-83°F
35%
84-85°F
21%
86-87°F
4%
88-89°F
3%
90-91°F
1%
92°F or higher
<1%
82-83°F 35%
80-81°F 30%
84-85°F 21%
78-79°F 10%
NEW
NEW
Aug 20, 2026
73°F or below
$93 Vol.
<1%
74-75°F
$13 Vol.
1%
76-77°F
$48 Vol.
5%
78-79°F
$20 Vol.
10%
80-81°F
$68 Vol.
30%
82-83°F
$30 Vol.
35%
84-85°F
$1 Vol.
21%
86-87°F
$1 Vol.
4%
88-89°F
$5 Vol.
3%
90-91°F
$80 Vol.
1%
92°F or higher
$191 Vol.
<1%
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Seattle-Tacoma International Airport Station, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.Current forecast guidance from the National Weather Service and other models shows Seattle's August 20 high most likely reaching 79–82°F under partly sunny skies and light onshore flow. Persistent marine air from the Pacific and Puget Sound continues to moderate daytime warming, preventing stronger heating despite seasonal solar input. Ensemble spreads remain modest, with limited model disagreement on cloud cover or wind shifts that could push readings into the mid-80s or hold them in the upper 70s. This distribution aligns with late-August climatology near Sea-Tac, where average highs hover around 77°F and extremes above 85°F are uncommon without offshore flow. Traders have concentrated probability in the 80–83°F range as the latest model runs converge on these values ahead of final observations.
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Seattle-Tacoma International Airport Station, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.
This market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Seattle-Tacoma International Airport Station, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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: Aug 18, 2026, 9:56 PM ET
Volume
$551End Date
Aug 20, 2026Market Opened
Aug 18, 2026, 9:56 PM ETResolution Source
https://www.wunderground.com/history/daily/us/wa/seatac/KSEAResolver
0x69c47De9D...This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Seattle-Tacoma International Airport Station, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.Current forecast guidance from the National Weather Service and other models shows Seattle's August 20 high most likely reaching 79–82°F under partly sunny skies and light onshore flow. Persistent marine air from the Pacific and Puget Sound continues to moderate daytime warming, preventing stronger heating despite seasonal solar input. Ensemble spreads remain modest, with limited model disagreement on cloud cover or wind shifts that could push readings into the mid-80s or hold them in the upper 70s. This distribution aligns with late-August climatology near Sea-Tac, where average highs hover around 77°F and extremes above 85°F are uncommon without offshore flow. Traders have concentrated probability in the 80–83°F range as the latest model runs converge on these values ahead of final observations.
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section.
This market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Seattle-Tacoma International Airport Station, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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.
This market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 20 Aug '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Seattle-Tacoma International Airport Station, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve until the first data point for the following date has been published on the resolution source.
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
$551End Date
Aug 20, 2026Market Opened
Aug 18, 2026, 9:56 PM ETResolution Source
https://www.wunderground.com/history/daily/us/wa/seatac/KSEAResolver
0x69c47De9D...Current forecast guidance from the National Weather Service and other models shows Seattle's August 20 high most likely reaching 79–82°F under partly sunny skies and light onshore flow. Persistent marine air from the Pacific and Puget Sound continues to moderate daytime warming, preventing stronger heating despite seasonal solar input. Ensemble spreads remain modest, with limited model disagreement on cloud cover or wind shifts that could push readings into the mid-80s or hold them in the upper 70s. This distribution aligns with late-August climatology near Sea-Tac, where average highs hover around 77°F and extremes above 85°F are uncommon without offshore flow. Traders have concentrated probability in the 80–83°F range as the latest model runs converge on these values ahead of final observations.
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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