Recent National Weather Service and model guidance point to a warming trend for San Francisco on September 19 driven by a short-wave ridge building over the Bay Area, which is expected to compress the marine layer and reduce onshore flow. This setup favors daytime highs in the low to mid-70s after cooler conditions earlier in the week tied to a cut-off low and deeper marine stratus. Key variables include the exact timing of cloud clearance, afternoon west-southwest winds near 10-15 mph, and local microclimate effects that can suppress coastal maxima by several degrees relative to inland sites. With forecasts clustered around 70-73°F and historical September averages near 71°F, trader sentiment reflects this narrow range of likely outcomes while allowing for modest upside if offshore influences strengthen.
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 19?
Highest temperature in San Francisco on September 19?
70-71°F 41%
72-73°F 27%
74-75°F 19%
68-69°F 18%
NEW
NEW
Sep 19, 2026
65°F or below
5%
66-67°F
7%
68-69°F
18%
70-71°F
41%
72-73°F
27%
74-75°F
19%
76-77°F
17%
78-79°F
12%
80-81°F
3%
82-83°F
2%
84°F or higher
1%
70-71°F 41%
72-73°F 27%
74-75°F 19%
68-69°F 18%
NEW
NEW
Sep 19, 2026
65°F or below
$0 Vol.
5%
66-67°F
$0 Vol.
7%
68-69°F
$80 Vol.
18%
70-71°F
$490 Vol.
41%
72-73°F
$116 Vol.
27%
74-75°F
$0 Vol.
19%
76-77°F
$0 Vol.
17%
78-79°F
$0 Vol.
12%
80-81°F
$0 Vol.
3%
82-83°F
$0 Vol.
2%
84°F or higher
$16 Vol.
1%
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 19 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 and model guidance point to a warming trend for San Francisco on September 19 driven by a short-wave ridge building over the Bay Area, which is expected to compress the marine layer and reduce onshore flow. This setup favors daytime highs in the low to mid-70s after cooler conditions earlier in the week tied to a cut-off low and deeper marine stratus. Key variables include the exact timing of cloud clearance, afternoon west-southwest winds near 10-15 mph, and local microclimate effects that can suppress coastal maxima by several degrees relative to inland sites. With forecasts clustered around 70-73°F and historical September averages near 71°F, trader sentiment reflects this narrow range of likely outcomes while allowing for modest upside if offshore influences strengthen.
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 19 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 17, 2026, 7:56 AM ET
Volume
$702End Date
Sep 19, 2026Market Opened
Sep 17, 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 19 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 and model guidance point to a warming trend for San Francisco on September 19 driven by a short-wave ridge building over the Bay Area, which is expected to compress the marine layer and reduce onshore flow. This setup favors daytime highs in the low to mid-70s after cooler conditions earlier in the week tied to a cut-off low and deeper marine stratus. Key variables include the exact timing of cloud clearance, afternoon west-southwest winds near 10-15 mph, and local microclimate effects that can suppress coastal maxima by several degrees relative to inland sites. With forecasts clustered around 70-73°F and historical September averages near 71°F, trader sentiment reflects this narrow range of likely outcomes while allowing for modest upside if offshore influences strengthen.
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 19 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
$702End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 7:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...Recent National Weather Service and model guidance point to a warming trend for San Francisco on September 19 driven by a short-wave ridge building over the Bay Area, which is expected to compress the marine layer and reduce onshore flow. This setup favors daytime highs in the low to mid-70s after cooler conditions earlier in the week tied to a cut-off low and deeper marine stratus. Key variables include the exact timing of cloud clearance, afternoon west-southwest winds near 10-15 mph, and local microclimate effects that can suppress coastal maxima by several degrees relative to inland sites. With forecasts clustered around 70-73°F and historical September averages near 71°F, trader sentiment reflects this narrow range of likely outcomes while allowing for modest upside if offshore influences strengthen.
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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