**Current forecasts from the National Weather Service and other models indicate a nighttime low near 58°F for San Francisco on September 19, aligning with the market's leading 58-59°F bin at 40.5% implied probability.** September climatology shows average lows of 55.8–56°F downtown, driven by the moderating influence of the cold California Current and coastal upwelling that sustains a marine layer. Recent observations confirm mild conditions with highs in the upper 60s to low 70s and dew points supporting efficient radiational cooling under partly cloudy skies, without strong offshore winds or clear, dry patterns that would push minima lower. Model consensus points to continued onshore flow and limited inland heat, keeping the minimum temperature clustered in the mid-to-upper 50s rather than deviating toward the lower-probability 54–55°F or 62–63°F outcomes. Updated NWS guidance and any shifts in marine-layer depth over the next 48 hours remain the key variables for traders.
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 19?
Lowest temperature in San Francisco on September 19?
58-59°F 55%
62-63°F 39%
56-57°F 31%
60-61°F 17%
NEW
NEW
Sep 19, 2026
51°F or below
5%
52-53°F
7%
54-55°F
11%
56-57°F
25%
58-59°F
42%
60-61°F
17%
62-63°F
39%
64-65°F
11%
66-67°F
7%
68-69°F
5%
70°F or higher
5%
58-59°F 55%
62-63°F 39%
56-57°F 31%
60-61°F 17%
NEW
NEW
Sep 19, 2026
51°F or below
$0 Vol.
5%
52-53°F
$0 Vol.
7%
54-55°F
$0 Vol.
11%
56-57°F
$11 Vol.
25%
58-59°F
$56 Vol.
42%
60-61°F
$132 Vol.
17%
62-63°F
$0 Vol.
39%
64-65°F
$0 Vol.
11%
66-67°F
$0 Vol.
7%
68-69°F
$0 Vol.
5%
70°F or higher
$0 Vol.
5%
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 19 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.**Current forecasts from the National Weather Service and other models indicate a nighttime low near 58°F for San Francisco on September 19, aligning with the market's leading 58-59°F bin at 40.5% implied probability.**
September climatology shows average lows of 55.8–56°F downtown, driven by the moderating influence of the cold California Current and coastal upwelling that sustains a marine layer. Recent observations confirm mild conditions with highs in the upper 60s to low 70s and dew points supporting efficient radiational cooling under partly cloudy skies, without strong offshore winds or clear, dry patterns that would push minima lower. Model consensus points to continued onshore flow and limited inland heat, keeping the minimum temperature clustered in the mid-to-upper 50s rather than deviating toward the lower-probability 54–55°F or 62–63°F outcomes. Updated NWS guidance and any shifts in marine-layer depth over the next 48 hours remain the key variables for traders.
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 19 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 17, 2026, 7:29 AM ET
Volume
$199End Date
Sep 19, 2026Market Opened
Sep 17, 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 19 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.**Current forecasts from the National Weather Service and other models indicate a nighttime low near 58°F for San Francisco on September 19, aligning with the market's leading 58-59°F bin at 40.5% implied probability.**
September climatology shows average lows of 55.8–56°F downtown, driven by the moderating influence of the cold California Current and coastal upwelling that sustains a marine layer. Recent observations confirm mild conditions with highs in the upper 60s to low 70s and dew points supporting efficient radiational cooling under partly cloudy skies, without strong offshore winds or clear, dry patterns that would push minima lower. Model consensus points to continued onshore flow and limited inland heat, keeping the minimum temperature clustered in the mid-to-upper 50s rather than deviating toward the lower-probability 54–55°F or 62–63°F outcomes. Updated NWS guidance and any shifts in marine-layer depth over the next 48 hours remain the key variables for traders.
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 19 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
$199End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 7:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...**Current forecasts from the National Weather Service and other models indicate a nighttime low near 58°F for San Francisco on September 19, aligning with the market's leading 58-59°F bin at 40.5% implied probability.** September climatology shows average lows of 55.8–56°F downtown, driven by the moderating influence of the cold California Current and coastal upwelling that sustains a marine layer. Recent observations confirm mild conditions with highs in the upper 60s to low 70s and dew points supporting efficient radiational cooling under partly cloudy skies, without strong offshore winds or clear, dry patterns that would push minima lower. Model consensus points to continued onshore flow and limited inland heat, keeping the minimum temperature clustered in the mid-to-upper 50s rather than deviating toward the lower-probability 54–55°F or 62–63°F outcomes. Updated NWS guidance and any shifts in marine-layer depth over the next 48 hours remain the key variables for traders.
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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