Latest National Weather Service guidance and ensemble model runs favor a San Francisco high near 68–70°F on August 21, driven by persistent onshore marine flow and a moderate westerly wind regime that limits inland heat advection to the coast. Typical August climatology shows a 67°F average high, with the current pattern featuring a stable marine layer and no strong offshore or subsidence warming expected overnight. Short-range forecasts from NOAA and private models converge on this range, though minor shifts in wind direction or cloud cover could nudge readings into the 66–71°F brackets that together hold roughly 87% of trader-implied probability. Updated model runs and the NWS morning forecast will provide the next key data points before resolution.
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 21?
Highest temperature in San Francisco on August 21?
68-69°F 42%
70-71°F 29%
66-67°F 17%
72-73°F 9%
NEW
NEW
Aug 21, 2026
61°F or below
1%
62-63°F
2%
64-65°F
4%
66-67°F
17%
68-69°F
42%
70-71°F
29%
72-73°F
9%
74-75°F
2%
76-77°F
1%
78-79°F
<1%
80°F or higher
<1%
68-69°F 42%
70-71°F 29%
66-67°F 17%
72-73°F 9%
NEW
NEW
Aug 21, 2026
61°F or below
$25 Vol.
1%
62-63°F
$55 Vol.
2%
64-65°F
$197 Vol.
4%
66-67°F
$335 Vol.
17%
68-69°F
$763 Vol.
42%
70-71°F
$60 Vol.
29%
72-73°F
$283 Vol.
9%
74-75°F
$843 Vol.
2%
76-77°F
$11 Vol.
1%
78-79°F
$15 Vol.
<1%
80°F or higher
$19 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 San Francisco International Airport Station in degrees Fahrenheit on 21 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.Latest National Weather Service guidance and ensemble model runs favor a San Francisco high near 68–70°F on August 21, driven by persistent onshore marine flow and a moderate westerly wind regime that limits inland heat advection to the coast. Typical August climatology shows a 67°F average high, with the current pattern featuring a stable marine layer and no strong offshore or subsidence warming expected overnight. Short-range forecasts from NOAA and private models converge on this range, though minor shifts in wind direction or cloud cover could nudge readings into the 66–71°F brackets that together hold roughly 87% of trader-implied probability. Updated model runs and the NWS morning forecast will provide the next key data points before resolution.
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 21 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 21 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 19, 2026, 9:57 PM ET
Volume
$2,607End Date
Aug 21, 2026Market Opened
Aug 19, 2026, 9:57 PM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
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 San Francisco International Airport Station in degrees Fahrenheit on 21 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.Latest National Weather Service guidance and ensemble model runs favor a San Francisco high near 68–70°F on August 21, driven by persistent onshore marine flow and a moderate westerly wind regime that limits inland heat advection to the coast. Typical August climatology shows a 67°F average high, with the current pattern featuring a stable marine layer and no strong offshore or subsidence warming expected overnight. Short-range forecasts from NOAA and private models converge on this range, though minor shifts in wind direction or cloud cover could nudge readings into the 66–71°F brackets that together hold roughly 87% of trader-implied probability. Updated model runs and the NWS morning forecast will provide the next key data points before resolution.
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 21 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 21 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
$2,607End Date
Aug 21, 2026Market Opened
Aug 19, 2026, 9:57 PM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOResolver
0x69c47De9D...Latest National Weather Service guidance and ensemble model runs favor a San Francisco high near 68–70°F on August 21, driven by persistent onshore marine flow and a moderate westerly wind regime that limits inland heat advection to the coast. Typical August climatology shows a 67°F average high, with the current pattern featuring a stable marine layer and no strong offshore or subsidence warming expected overnight. Short-range forecasts from NOAA and private models converge on this range, though minor shifts in wind direction or cloud cover could nudge readings into the 66–71°F brackets that together hold roughly 87% of trader-implied probability. Updated model runs and the NWS morning forecast will provide the next key data points before resolution.
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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