Latest National Weather Service forecasts and ensemble model guidance point to a daytime high in the upper 60s for San Francisco today, shaped by a persistent marine layer and moderate onshore flow that restricts solar heating along the immediate coast. Trader consensus clusters around 68–71°F because small differences in cloud timing, wind speed, or local sheltering can shift the exact peak by a degree or two, while historical May averages near 64–67°F and recent above-normal trends add modest upside potential. The official resolution will rely on the National Weather Service’s daily climatological report from the designated San Francisco station, with final readings typically available within hours of sunset.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in San Francisco on May 21?
Highest temperature in San Francisco on May 21?
68-69°F 34%
70-71°F 27.0%
72-73°F 17%
66-67°F 10.9%
NEW
$10,890 Vol.
NEW
$10,890 Vol.
May 21, 2026
57°F or below
<1%
58-59°F
<1%
60-61°F
1%
62-63°F
1%
64-65°F
5%
66-67°F
11%
68-69°F
34%
70-71°F
27%
72-73°F
17%
74-75°F
5%
76°F or higher
3%
68-69°F 34%
70-71°F 27.0%
72-73°F 17%
66-67°F 10.9%
NEW
$10,890 Vol.
NEW
$10,890 Vol.
May 21, 2026
57°F or below
$1,837 Vol.
<1%
58-59°F
$1,018 Vol.
<1%
60-61°F
$426 Vol.
1%
62-63°F
$633 Vol.
1%
64-65°F
$616 Vol.
5%
66-67°F
$1,030 Vol.
11%
68-69°F
$1,116 Vol.
34%
70-71°F
$841 Vol.
27%
72-73°F
$780 Vol.
17%
74-75°F
$982 Vol.
5%
76°F or higher
$1,681 Vol.
3%
This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 21 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 San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
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.Latest National Weather Service forecasts and ensemble model guidance point to a daytime high in the upper 60s for San Francisco today, shaped by a persistent marine layer and moderate onshore flow that restricts solar heating along the immediate coast. Trader consensus clusters around 68–71°F because small differences in cloud timing, wind speed, or local sheltering can shift the exact peak by a degree or two, while historical May averages near 64–67°F and recent above-normal trends add modest upside potential. The official resolution will rely on the National Weather Service’s daily climatological report from the designated San Francisco station, with final readings typically available within hours of sunset.
This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 21 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 San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
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 San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
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 19, 2026, 12:07 AM ET
Volume
$10,890End Date
May 21, 2026Market Opened
May 19, 2026, 12:07 AM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 21 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 San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
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.Latest National Weather Service forecasts and ensemble model guidance point to a daytime high in the upper 60s for San Francisco today, shaped by a persistent marine layer and moderate onshore flow that restricts solar heating along the immediate coast. Trader consensus clusters around 68–71°F because small differences in cloud timing, wind speed, or local sheltering can shift the exact peak by a degree or two, while historical May averages near 64–67°F and recent above-normal trends add modest upside potential. The official resolution will rely on the National Weather Service’s daily climatological report from the designated San Francisco station, with final readings typically available within hours of sunset.
This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 21 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 San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
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 San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
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
$10,890End Date
May 21, 2026Market Opened
May 19, 2026, 12:07 AM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
0x69c47De9D...Latest National Weather Service forecasts and ensemble model guidance point to a daytime high in the upper 60s for San Francisco today, shaped by a persistent marine layer and moderate onshore flow that restricts solar heating along the immediate coast. Trader consensus clusters around 68–71°F because small differences in cloud timing, wind speed, or local sheltering can shift the exact peak by a degree or two, while historical May averages near 64–67°F and recent above-normal trends add modest upside potential. The official resolution will rely on the National Weather Service’s daily climatological report from the designated San Francisco station, with final readings typically available within hours of sunset.
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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