Current National Weather Service and ensemble forecast models project a daytime high of 62–64°F for Seattle on May 18, driven by mild onshore flow and stable spring ridging with no significant cold-air advection expected. This aligns with regional climatology, where May average highs reach 65°F and sub-58°F readings occur in fewer than 5% of years at Sea-Tac. Trader consensus has priced the 58°F-or-higher outcome at 99.6% because model spreads remain narrow through the weekend, with only minor variability in cloud cover or timing of any weak front. A realistic challenge would require an unforecasted marine push or rapid overnight clearing that allows greater radiational cooling, though such shifts are rare this late in the season and would need to overcome the current 10–15°F buffer above the threshold.
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 May 18?
Highest temperature in Seattle on May 18?
58°F or higher 99.6%
46-47°F <1%
56-57°F <1%
42-43°F <1%
NEW
$10,385 Vol.
NEW
$10,385 Vol.
May 18, 2026
39°F or below
<1%
40-41°F
<1%
42-43°F
<1%
44-45°F
<1%
46-47°F
<1%
48-49°F
<1%
50-51°F
<1%
52-53°F
<1%
54-55°F
<1%
56-57°F
<1%
58°F or higher
100%
58°F or higher 99.6%
46-47°F <1%
56-57°F <1%
42-43°F <1%
NEW
$10,385 Vol.
NEW
$10,385 Vol.
May 18, 2026
39°F or below
$881 Vol.
<1%
40-41°F
$890 Vol.
<1%
42-43°F
$651 Vol.
<1%
44-45°F
$821 Vol.
<1%
46-47°F
$944 Vol.
<1%
48-49°F
$864 Vol.
<1%
50-51°F
$766 Vol.
<1%
52-53°F
$1,211 Vol.
<1%
54-55°F
$1,082 Vol.
<1%
56-57°F
$1,266 Vol.
<1%
58°F or higher
$1,009 Vol.
100%
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 18 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Current National Weather Service and ensemble forecast models project a daytime high of 62–64°F for Seattle on May 18, driven by mild onshore flow and stable spring ridging with no significant cold-air advection expected. This aligns with regional climatology, where May average highs reach 65°F and sub-58°F readings occur in fewer than 5% of years at Sea-Tac. Trader consensus has priced the 58°F-or-higher outcome at 99.6% because model spreads remain narrow through the weekend, with only minor variability in cloud cover or timing of any weak front. A realistic challenge would require an unforecasted marine push or rapid overnight clearing that allows greater radiational cooling, though such shifts are rare this late in the season and would need to overcome the current 10–15°F buffer above the threshold.
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 18 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: May 16, 2026, 12:03 AM ET
Volume
$10,385End Date
May 18, 2026Market Opened
May 16, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/us/wa/seatac/KSEAThis market will resolve to the temperature range that contains the highest temperature recorded at the Seattle-Tacoma International Airport Station in degrees Fahrenheit on 18 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Current National Weather Service and ensemble forecast models project a daytime high of 62–64°F for Seattle on May 18, driven by mild onshore flow and stable spring ridging with no significant cold-air advection expected. This aligns with regional climatology, where May average highs reach 65°F and sub-58°F readings occur in fewer than 5% of years at Sea-Tac. Trader consensus has priced the 58°F-or-higher outcome at 99.6% because model spreads remain narrow through the weekend, with only minor variability in cloud cover or timing of any weak front. A realistic challenge would require an unforecasted marine push or rapid overnight clearing that allows greater radiational cooling, though such shifts are rare this late in the season and would need to overcome the current 10–15°F buffer above the threshold.
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 18 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, 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 to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$10,385End Date
May 18, 2026Market Opened
May 16, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/us/wa/seatac/KSEACurrent National Weather Service and ensemble forecast models project a daytime high of 62–64°F for Seattle on May 18, driven by mild onshore flow and stable spring ridging with no significant cold-air advection expected. This aligns with regional climatology, where May average highs reach 65°F and sub-58°F readings occur in fewer than 5% of years at Sea-Tac. Trader consensus has priced the 58°F-or-higher outcome at 99.6% because model spreads remain narrow through the weekend, with only minor variability in cloud cover or timing of any weak front. A realistic challenge would require an unforecasted marine push or rapid overnight clearing that allows greater radiational cooling, though such shifts are rare this late in the season and would need to overcome the current 10–15°F buffer above the threshold.
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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