Trader consensus has converged on an implied probability of 100% for a highest temperature of 68–69°F on August 18 in San Francisco, driven by the official observation at the primary reporting station reaching a peak of 67–69°F under typical marine-layer influence and moderate onshore flow. National Weather Service data confirmed the daily maximum occurred near 1:43 PM, consistent with August climatology where average highs hover near 67–70°F and coastal cooling from the Pacific prevents stronger warming. This outcome aligns with model guidance and real-time measurements showing no significant heat advection from inland valleys. A shift to higher brackets would have required an anomalous offshore wind pattern or clear-sky subsidence strengthening, neither of which materialized in the final forecast updates or 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 San Francisco on August 18?
Highest temperature in San Francisco on August 18?
68-69°F 100.0%
67°F or below <1%
70-71°F <1%
72-73°F <1%
$38,288 Vol.
$38,288 Vol.
Aug 18, 2026
67°F or below
No
68-69°F
Yes
70-71°F
No
72-73°F
No
74-75°F
No
76-77°F
No
78-79°F
No
80-81°F
No
82-83°F
No
84-85°F
No
86°F or higher
No
68-69°F 100.0%
67°F or below <1%
70-71°F <1%
72-73°F <1%
$38,288 Vol.
$38,288 Vol.
Aug 18, 2026
67°F or below
$5,985 Vol.
No
68-69°F
$5,726 Vol.
Yes
70-71°F
$7,952 Vol.
No
72-73°F
$7,226 Vol.
No
74-75°F
$3,119 Vol.
No
76-77°F
$3,526 Vol.
No
78-79°F
$2,330 Vol.
No
80-81°F
$1,214 Vol.
No
82-83°F
$541 Vol.
No
84-85°F
$560 Vol.
No
86°F or higher
$110 Vol.
No
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 San Francisco International Airport Station in degrees Fahrenheit on 18 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 San Francisco International Airport Station, 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 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.Trader consensus has converged on an implied probability of 100% for a highest temperature of 68–69°F on August 18 in San Francisco, driven by the official observation at the primary reporting station reaching a peak of 67–69°F under typical marine-layer influence and moderate onshore flow. National Weather Service data confirmed the daily maximum occurred near 1:43 PM, consistent with August climatology where average highs hover near 67–70°F and coastal cooling from the Pacific prevents stronger warming. This outcome aligns with model guidance and real-time measurements showing no significant heat advection from inland valleys. A shift to higher brackets would have required an anomalous offshore wind pattern or clear-sky subsidence strengthening, neither of which materialized in the final forecast updates or 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 San Francisco International Airport Station in degrees Fahrenheit on 18 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 San Francisco International Airport Station, 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 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 San Francisco International Airport Station in degrees Fahrenheit on 18 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 San Francisco International Airport Station, 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 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 16, 2026, 9:57 PM ET
Volume
$38,288End Date
Aug 18, 2026Market Opened
Aug 16, 2026, 9:57 PM 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 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 San Francisco International Airport Station in degrees Fahrenheit on 18 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 San Francisco International Airport Station, 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 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.Trader consensus has converged on an implied probability of 100% for a highest temperature of 68–69°F on August 18 in San Francisco, driven by the official observation at the primary reporting station reaching a peak of 67–69°F under typical marine-layer influence and moderate onshore flow. National Weather Service data confirmed the daily maximum occurred near 1:43 PM, consistent with August climatology where average highs hover near 67–70°F and coastal cooling from the Pacific prevents stronger warming. This outcome aligns with model guidance and real-time measurements showing no significant heat advection from inland valleys. A shift to higher brackets would have required an anomalous offshore wind pattern or clear-sky subsidence strengthening, neither of which materialized in the final forecast updates or 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 San Francisco International Airport Station in degrees Fahrenheit on 18 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 San Francisco International Airport Station, 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 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 San Francisco International Airport Station in degrees Fahrenheit on 18 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 San Francisco International Airport Station, 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 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
$38,288End Date
Aug 18, 2026Market Opened
Aug 16, 2026, 9:57 PM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Trader consensus has converged on an implied probability of 100% for a highest temperature of 68–69°F on August 18 in San Francisco, driven by the official observation at the primary reporting station reaching a peak of 67–69°F under typical marine-layer influence and moderate onshore flow. National Weather Service data confirmed the daily maximum occurred near 1:43 PM, consistent with August climatology where average highs hover near 67–70°F and coastal cooling from the Pacific prevents stronger warming. This outcome aligns with model guidance and real-time measurements showing no significant heat advection from inland valleys. A shift to higher brackets would have required an anomalous offshore wind pattern or clear-sky subsidence strengthening, neither of which materialized in the final forecast updates or 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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