**Recent forecasts from National Weather Service-aligned sources and models indicate a low temperature for San Francisco on September 22 in the upper 50s, with most runs centering on 56–58°F.** This aligns closely with the market’s leading outcomes—58–59°F at 46.5% implied probability and 56–57°F at 32.0%—as traders incorporate the latest model consensus showing continued marine-layer influence and onshore southwest flow. Typical September climatology supports this range, with a long-term average low near 55.7°F and minimal day-to-day variability absent strong synoptic changes. Current conditions feature mild highs in the mid-60s, high humidity, and light winds that limit nocturnal cooling, while the absence of offshore flow or clear-sky radiational cooling keeps the floor elevated. No significant frontal passages or heat anomalies are expected overnight into the 22nd, so probabilities cluster tightly around the upper-50s bins. Updated NWS and ensemble guidance released in the next 12–24 hours will provide the final observational anchor 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 22?
Lowest temperature in San Francisco on September 22?
51°F or below 77%
70°F or higher 72%
52-53°F 39%
64-65°F 39%
NEW
NEW
Sep 22, 2026
51°F or below
77%
52-53°F
39%
54-55°F
21%
56-57°F
29%
58-59°F
34%
60-61°F
22%
62-63°F
21%
64-65°F
39%
66-67°F
39%
68-69°F
39%
70°F or higher
72%
51°F or below 77%
70°F or higher 72%
52-53°F 39%
64-65°F 39%
NEW
NEW
Sep 22, 2026
51°F or below
$10 Vol.
77%
52-53°F
$58 Vol.
39%
54-55°F
$0 Vol.
21%
56-57°F
$71 Vol.
29%
58-59°F
$97 Vol.
34%
60-61°F
$0 Vol.
22%
62-63°F
$0 Vol.
21%
64-65°F
$10 Vol.
39%
66-67°F
$10 Vol.
39%
68-69°F
$10 Vol.
39%
70°F or higher
$10 Vol.
72%
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 22 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.**Recent forecasts from National Weather Service-aligned sources and models indicate a low temperature for San Francisco on September 22 in the upper 50s, with most runs centering on 56–58°F.** This aligns closely with the market’s leading outcomes—58–59°F at 46.5% implied probability and 56–57°F at 32.0%—as traders incorporate the latest model consensus showing continued marine-layer influence and onshore southwest flow.
Typical September climatology supports this range, with a long-term average low near 55.7°F and minimal day-to-day variability absent strong synoptic changes. Current conditions feature mild highs in the mid-60s, high humidity, and light winds that limit nocturnal cooling, while the absence of offshore flow or clear-sky radiational cooling keeps the floor elevated. No significant frontal passages or heat anomalies are expected overnight into the 22nd, so probabilities cluster tightly around the upper-50s bins. Updated NWS and ensemble guidance released in the next 12–24 hours will provide the final observational anchor 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 22 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 20, 2026, 7:29 AM ET
Volume
$277End Date
Sep 22, 2026Market Opened
Sep 20, 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 22 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.**Recent forecasts from National Weather Service-aligned sources and models indicate a low temperature for San Francisco on September 22 in the upper 50s, with most runs centering on 56–58°F.** This aligns closely with the market’s leading outcomes—58–59°F at 46.5% implied probability and 56–57°F at 32.0%—as traders incorporate the latest model consensus showing continued marine-layer influence and onshore southwest flow.
Typical September climatology supports this range, with a long-term average low near 55.7°F and minimal day-to-day variability absent strong synoptic changes. Current conditions feature mild highs in the mid-60s, high humidity, and light winds that limit nocturnal cooling, while the absence of offshore flow or clear-sky radiational cooling keeps the floor elevated. No significant frontal passages or heat anomalies are expected overnight into the 22nd, so probabilities cluster tightly around the upper-50s bins. Updated NWS and ensemble guidance released in the next 12–24 hours will provide the final observational anchor 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 22 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
$277End Date
Sep 22, 2026Market Opened
Sep 20, 2026, 7:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...**Recent forecasts from National Weather Service-aligned sources and models indicate a low temperature for San Francisco on September 22 in the upper 50s, with most runs centering on 56–58°F.** This aligns closely with the market’s leading outcomes—58–59°F at 46.5% implied probability and 56–57°F at 32.0%—as traders incorporate the latest model consensus showing continued marine-layer influence and onshore southwest flow. Typical September climatology supports this range, with a long-term average low near 55.7°F and minimal day-to-day variability absent strong synoptic changes. Current conditions feature mild highs in the mid-60s, high humidity, and light winds that limit nocturnal cooling, while the absence of offshore flow or clear-sky radiational cooling keeps the floor elevated. No significant frontal passages or heat anomalies are expected overnight into the 22nd, so probabilities cluster tightly around the upper-50s bins. Updated NWS and ensemble guidance released in the next 12–24 hours will provide the final observational anchor 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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