**Forecasts from the National Weather Service and other models indicate the overnight low into September 17 will likely reach the upper 50s°F (around 58–59°F), driven by persistent onshore flow and a moderate marine layer off the Pacific.** This keeps San Francisco’s coastal microclimate cooler than inland areas, with dew points in the mid-50s and light westerly winds limiting radiative cooling overnight. Historical September averages hover near 56°F for lows, but recent model runs show slightly warmer conditions due to above-normal sea surface temperatures and limited fog development. The leading market outcome (60–61°F at 43% implied probability) reflects trader expectations of minimal overnight drop, while the notable share on 51°F or below (35.5%) appears to price in a stronger marine push or clearer skies allowing more cooling than current guidance supports. Key variables for the final minimum include the exact timing of any drizzle or cloud cover on the night of the 16th–17th and wind shifts, with updated NWS and NOAA model runs expected to refine these details before resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in San Francisco on September 17?
Lowest temperature in San Francisco on September 17?
51°F or below 55%
70°F or higher 55%
60-61°F 52%
58-59°F 44%
NEW
NEW
Sep 17, 2026
51°F or below
55%
52-53°F
30%
54-55°F
30%
56-57°F
30%
58-59°F
29%
60-61°F
43%
62-63°F
39%
64-65°F
39%
66-67°F
5%
68-69°F
14%
70°F or higher
55%
51°F or below 55%
70°F or higher 55%
60-61°F 52%
58-59°F 44%
NEW
NEW
Sep 17, 2026
51°F or below
$0 Vol.
55%
52-53°F
$0 Vol.
30%
54-55°F
$0 Vol.
30%
56-57°F
$0 Vol.
30%
58-59°F
$44 Vol.
29%
60-61°F
$30 Vol.
43%
62-63°F
$0 Vol.
39%
64-65°F
$0 Vol.
39%
66-67°F
$0 Vol.
5%
68-69°F
$0 Vol.
14%
70°F or higher
$0 Vol.
55%
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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.**Forecasts from the National Weather Service and other models indicate the overnight low into September 17 will likely reach the upper 50s°F (around 58–59°F), driven by persistent onshore flow and a moderate marine layer off the Pacific.** This keeps San Francisco’s coastal microclimate cooler than inland areas, with dew points in the mid-50s and light westerly winds limiting radiative cooling overnight.
Historical September averages hover near 56°F for lows, but recent model runs show slightly warmer conditions due to above-normal sea surface temperatures and limited fog development. The leading market outcome (60–61°F at 43% implied probability) reflects trader expectations of minimal overnight drop, while the notable share on 51°F or below (35.5%) appears to price in a stronger marine push or clearer skies allowing more cooling than current guidance supports.
Key variables for the final minimum include the exact timing of any drizzle or cloud cover on the night of the 16th–17th and wind shifts, with updated NWS and NOAA model runs expected to refine these details before resolution.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 lowest 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 15, 2026, 7:29 AM ET
Volume
$74End Date
Sep 17, 2026Market Opened
Sep 15, 2026, 7:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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.**Forecasts from the National Weather Service and other models indicate the overnight low into September 17 will likely reach the upper 50s°F (around 58–59°F), driven by persistent onshore flow and a moderate marine layer off the Pacific.** This keeps San Francisco’s coastal microclimate cooler than inland areas, with dew points in the mid-50s and light westerly winds limiting radiative cooling overnight.
Historical September averages hover near 56°F for lows, but recent model runs show slightly warmer conditions due to above-normal sea surface temperatures and limited fog development. The leading market outcome (60–61°F at 43% implied probability) reflects trader expectations of minimal overnight drop, while the notable share on 51°F or below (35.5%) appears to price in a stronger marine push or clearer skies allowing more cooling than current guidance supports.
Key variables for the final minimum include the exact timing of any drizzle or cloud cover on the night of the 16th–17th and wind shifts, with updated NWS and NOAA model runs expected to refine these details before resolution.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the San Francisco International Airport Station in degrees Fahrenheit on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 lowest 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
$74End Date
Sep 17, 2026Market Opened
Sep 15, 2026, 7:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...**Forecasts from the National Weather Service and other models indicate the overnight low into September 17 will likely reach the upper 50s°F (around 58–59°F), driven by persistent onshore flow and a moderate marine layer off the Pacific.** This keeps San Francisco’s coastal microclimate cooler than inland areas, with dew points in the mid-50s and light westerly winds limiting radiative cooling overnight. Historical September averages hover near 56°F for lows, but recent model runs show slightly warmer conditions due to above-normal sea surface temperatures and limited fog development. The leading market outcome (60–61°F at 43% implied probability) reflects trader expectations of minimal overnight drop, while the notable share on 51°F or below (35.5%) appears to price in a stronger marine push or clearer skies allowing more cooling than current guidance supports. Key variables for the final minimum include the exact timing of any drizzle or cloud cover on the night of the 16th–17th and wind shifts, with updated NWS and NOAA model runs expected to refine these details 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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