Official observations from Weather Underground at San Francisco International Airport (KSFO)—the market's resolution source—confirm the highest temperature on April 21, 2026, reached 62°F around midday under mostly cloudy skies with 0.65 inches of light rain and gusty winds up to 26 mph, aligning perfectly with trader consensus at 100% implied probability for 62-63°F. This outcome reflects persistent marine layer influence and cool Pacific air masses typical for mid-April in San Francisco, where historical daily highs average 63-65°F amid frequent fog and drizzle. National Weather Service data similarly reports a peak near 63°F with light rain, reinforcing the positioning. Realistic challenges would require a rare data revision from automated sensors or station metadata corrections, though such adjustments are infrequent post-preliminary reporting.
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 April 21?
Highest temperature in San Francisco on April 21?
62-63°F 100.0%
51°F or below <1%
52-53°F <1%
54-55°F <1%
$101,526 Vol.
$101,526 Vol.
Apr 21, 2026
51°F or below
No
52-53°F
No
54-55°F
No
56-57°F
No
58-59°F
No
60-61°F
No
62-63°F
Yes
64-65°F
No
66-67°F
No
68-69°F
No
70°F or higher
No
62-63°F 100.0%
51°F or below <1%
52-53°F <1%
54-55°F <1%
$101,526 Vol.
$101,526 Vol.
Apr 21, 2026
51°F or below
$1,764 Vol.
No
52-53°F
$1,977 Vol.
No
54-55°F
$9,839 Vol.
No
56-57°F
$9,924 Vol.
No
58-59°F
$6,623 Vol.
No
60-61°F
$22,073 Vol.
No
62-63°F
$14,467 Vol.
Yes
64-65°F
$12,534 Vol.
No
66-67°F
$7,069 Vol.
No
68-69°F
$7,303 Vol.
No
70°F or higher
$7,952 Vol.
No
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 Apr '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.Official observations from Weather Underground at San Francisco International Airport (KSFO)—the market's resolution source—confirm the highest temperature on April 21, 2026, reached 62°F around midday under mostly cloudy skies with 0.65 inches of light rain and gusty winds up to 26 mph, aligning perfectly with trader consensus at 100% implied probability for 62-63°F. This outcome reflects persistent marine layer influence and cool Pacific air masses typical for mid-April in San Francisco, where historical daily highs average 63-65°F amid frequent fog and drizzle. National Weather Service data similarly reports a peak near 63°F with light rain, reinforcing the positioning. Realistic challenges would require a rare data revision from automated sensors or station metadata corrections, though such adjustments are infrequent post-preliminary reporting.
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 Apr '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: Apr 19, 2026, 12:14 AM ET
Volume
$101,526End Date
Apr 21, 2026Market Opened
Apr 19, 2026, 12:14 AM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
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 Apr '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.Official observations from Weather Underground at San Francisco International Airport (KSFO)—the market's resolution source—confirm the highest temperature on April 21, 2026, reached 62°F around midday under mostly cloudy skies with 0.65 inches of light rain and gusty winds up to 26 mph, aligning perfectly with trader consensus at 100% implied probability for 62-63°F. This outcome reflects persistent marine layer influence and cool Pacific air masses typical for mid-April in San Francisco, where historical daily highs average 63-65°F amid frequent fog and drizzle. National Weather Service data similarly reports a peak near 63°F with light rain, reinforcing the positioning. Realistic challenges would require a rare data revision from automated sensors or station metadata corrections, though such adjustments are infrequent post-preliminary reporting.
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 Apr '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
$101,526End Date
Apr 21, 2026Market Opened
Apr 19, 2026, 12:14 AM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Official observations from Weather Underground at San Francisco International Airport (KSFO)—the market's resolution source—confirm the highest temperature on April 21, 2026, reached 62°F around midday under mostly cloudy skies with 0.65 inches of light rain and gusty winds up to 26 mph, aligning perfectly with trader consensus at 100% implied probability for 62-63°F. This outcome reflects persistent marine layer influence and cool Pacific air masses typical for mid-April in San Francisco, where historical daily highs average 63-65°F amid frequent fog and drizzle. National Weather Service data similarly reports a peak near 63°F with light rain, reinforcing the positioning. Realistic challenges would require a rare data revision from automated sensors or station metadata corrections, though such adjustments are infrequent post-preliminary reporting.
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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