Forecast consensus from NWS and ensemble models points to a Friday minimum in the upper 50s to low 60s °F for San Francisco, driven by persistent onshore westerly flow and a moderating marine layer that limits nocturnal cooling despite mostly clear skies. Light winds and dew points near 55–60 °F further anchor overnight lows near the long-term September 18 average of 55.8 °F, with recent observations showing similar 56–59 °F readings under comparable conditions. Model spread and San Francisco’s microclimates create the tight clustering of trader-implied odds around 58–63 °F bins, as small shifts in boundary-layer moisture or wind could alter the exact low by a degree or two before resolution. Updated NWS guidance and high-resolution runs remain the key near-term catalysts.
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 18?
Lowest temperature in San Francisco on September 18?
58-59°F 51%
60-61°F 34%
62-63°F 33%
56-57°F 22%
NEW
NEW
Sep 18, 2026
51°F or below
5%
52-53°F
7%
54-55°F
11%
56-57°F
31%
58-59°F
51%
60-61°F
34%
62-63°F
33%
64-65°F
18%
66-67°F
11%
68-69°F
7%
70°F or higher
5%
58-59°F 51%
60-61°F 34%
62-63°F 33%
56-57°F 22%
NEW
NEW
Sep 18, 2026
51°F or below
$0 Vol.
5%
52-53°F
$0 Vol.
7%
54-55°F
$0 Vol.
11%
56-57°F
$88 Vol.
31%
58-59°F
$64 Vol.
51%
60-61°F
$0 Vol.
34%
62-63°F
$0 Vol.
33%
64-65°F
$0 Vol.
18%
66-67°F
$0 Vol.
11%
68-69°F
$0 Vol.
7%
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 18 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.Forecast consensus from NWS and ensemble models points to a Friday minimum in the upper 50s to low 60s °F for San Francisco, driven by persistent onshore westerly flow and a moderating marine layer that limits nocturnal cooling despite mostly clear skies. Light winds and dew points near 55–60 °F further anchor overnight lows near the long-term September 18 average of 55.8 °F, with recent observations showing similar 56–59 °F readings under comparable conditions. Model spread and San Francisco’s microclimates create the tight clustering of trader-implied odds around 58–63 °F bins, as small shifts in boundary-layer moisture or wind could alter the exact low by a degree or two before resolution. Updated NWS guidance and high-resolution runs remain the key near-term catalysts.
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 18 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 16, 2026, 7:29 AM ET
Volume
$151End Date
Sep 18, 2026Market Opened
Sep 16, 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 18 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.Forecast consensus from NWS and ensemble models points to a Friday minimum in the upper 50s to low 60s °F for San Francisco, driven by persistent onshore westerly flow and a moderating marine layer that limits nocturnal cooling despite mostly clear skies. Light winds and dew points near 55–60 °F further anchor overnight lows near the long-term September 18 average of 55.8 °F, with recent observations showing similar 56–59 °F readings under comparable conditions. Model spread and San Francisco’s microclimates create the tight clustering of trader-implied odds around 58–63 °F bins, as small shifts in boundary-layer moisture or wind could alter the exact low by a degree or two before resolution. Updated NWS guidance and high-resolution runs remain the key near-term catalysts.
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 18 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
$151End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 7:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...Forecast consensus from NWS and ensemble models points to a Friday minimum in the upper 50s to low 60s °F for San Francisco, driven by persistent onshore westerly flow and a moderating marine layer that limits nocturnal cooling despite mostly clear skies. Light winds and dew points near 55–60 °F further anchor overnight lows near the long-term September 18 average of 55.8 °F, with recent observations showing similar 56–59 °F readings under comparable conditions. Model spread and San Francisco’s microclimates create the tight clustering of trader-implied odds around 58–63 °F bins, as small shifts in boundary-layer moisture or wind could alter the exact low by a degree or two before resolution. Updated NWS guidance and high-resolution runs remain the key near-term catalysts.
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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