Recent National Weather Service guidance and ensemble model runs point to a San Francisco high near 70°F on September 25, driven by moderate onshore westerly flow and limited marine-layer stratus that typically caps afternoon warming along the coast. Historical September 25 averages near 71°F provide context, yet day-to-day variability from exact wind timing, fog clearance, and urban heat-island effects creates a broad distribution of possible maxima. With market-implied probabilities evenly distributed across 61–80°F+ bins, traders appear to price in genuine forecast uncertainty rather than a single dominant outcome, consistent with the narrow spread in official guidance and the resolution sensitivity of narrow temperature thresholds. Updated model runs and NWS briefings through Friday morning will likely refine the range.
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 September 25?
Highest temperature in San Francisco on September 25?
70-71°F 25%
72-73°F 24%
68-69°F 20%
66-67°F 15%
NEW
NEW
Sep 25, 2026
61°F or below
4%
62-63°F
3%
64-65°F
5%
66-67°F
15%
68-69°F
20%
70-71°F
25%
72-73°F
24%
74-75°F
7%
76-77°F
12%
78-79°F
6%
80°F or higher
5%
70-71°F 25%
72-73°F 24%
68-69°F 20%
66-67°F 15%
NEW
NEW
Sep 25, 2026
61°F or below
$10 Vol.
4%
62-63°F
$2 Vol.
3%
64-65°F
$0 Vol.
5%
66-67°F
$0 Vol.
15%
68-69°F
$0 Vol.
20%
70-71°F
$0 Vol.
25%
72-73°F
$0 Vol.
24%
74-75°F
$0 Vol.
7%
76-77°F
$0 Vol.
12%
78-79°F
$10 Vol.
6%
80°F or higher
$10 Vol.
5%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 25 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksfo
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.Recent National Weather Service guidance and ensemble model runs point to a San Francisco high near 70°F on September 25, driven by moderate onshore westerly flow and limited marine-layer stratus that typically caps afternoon warming along the coast. Historical September 25 averages near 71°F provide context, yet day-to-day variability from exact wind timing, fog clearance, and urban heat-island effects creates a broad distribution of possible maxima. With market-implied probabilities evenly distributed across 61–80°F+ bins, traders appear to price in genuine forecast uncertainty rather than a single dominant outcome, consistent with the narrow spread in official guidance and the resolution sensitivity of narrow temperature thresholds. Updated model runs and NWS briefings through Friday morning will likely refine the range.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 25 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksfo
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksfo
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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: Sep 23, 2026, 7:56 AM ET
Volume
$32End Date
Sep 25, 2026Market Opened
Sep 23, 2026, 7:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 25 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksfo
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.Recent National Weather Service guidance and ensemble model runs point to a San Francisco high near 70°F on September 25, driven by moderate onshore westerly flow and limited marine-layer stratus that typically caps afternoon warming along the coast. Historical September 25 averages near 71°F provide context, yet day-to-day variability from exact wind timing, fog clearance, and urban heat-island effects creates a broad distribution of possible maxima. With market-implied probabilities evenly distributed across 61–80°F+ bins, traders appear to price in genuine forecast uncertainty rather than a single dominant outcome, consistent with the narrow spread in official guidance and the resolution sensitivity of narrow temperature thresholds. Updated model runs and NWS briefings through Friday morning will likely refine the range.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 25 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksfo
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=ksfo
This market will resolve off of the Hourly Data provided using the "Show Hourly Data" button.
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to US Units w/ kts" button until the relevant table displays °F.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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
$32End Date
Sep 25, 2026Market Opened
Sep 23, 2026, 7:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...Recent National Weather Service guidance and ensemble model runs point to a San Francisco high near 70°F on September 25, driven by moderate onshore westerly flow and limited marine-layer stratus that typically caps afternoon warming along the coast. Historical September 25 averages near 71°F provide context, yet day-to-day variability from exact wind timing, fog clearance, and urban heat-island effects creates a broad distribution of possible maxima. With market-implied probabilities evenly distributed across 61–80°F+ bins, traders appear to price in genuine forecast uncertainty rather than a single dominant outcome, consistent with the narrow spread in official guidance and the resolution sensitivity of narrow temperature thresholds. Updated model runs and NWS briefings through Friday morning will likely refine the range.
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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