Trader consensus centers on 70-75°F for San Francisco’s September 18 high, with 70-71°F the single most favored bin at 33% implied probability, reflecting the moderating influence of the marine layer and typical onshore westerly flow that caps daytime warming near the long-term average of 70.8°F. Recent model runs show highs in the upper 60s to mid-70s depending on the strength of the inversion and any breaks in coastal stratus, while historical September variability and current neutral ENSO conditions sustain the broad distribution. Key variables include wind direction and speed, which control advection of cooler Pacific air, plus the timing of any clearing that could allow brief warming above 75°F. Updated National Weather Service guidance and morning soundings ahead of the date remain the primary near-term catalysts.
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 18?
Highest temperature in San Francisco on September 18?
72-73°F 39%
70-71°F 25%
74-75°F 25%
76-77°F 17%
NEW
NEW
Sep 18, 2026
63°F or below
5%
64-65°F
5%
66-67°F
7%
68-69°F
11%
70-71°F
36%
72-73°F
39%
74-75°F
25%
76-77°F
17%
78-79°F
10%
80-81°F
6%
82°F or higher
4%
72-73°F 39%
70-71°F 25%
74-75°F 25%
76-77°F 17%
NEW
NEW
Sep 18, 2026
63°F or below
$0 Vol.
5%
64-65°F
$0 Vol.
5%
66-67°F
$0 Vol.
7%
68-69°F
$0 Vol.
11%
70-71°F
$14 Vol.
36%
72-73°F
$0 Vol.
39%
74-75°F
$0 Vol.
25%
76-77°F
$0 Vol.
17%
78-79°F
$0 Vol.
10%
80-81°F
$0 Vol.
6%
82°F or higher
$0 Vol.
4%
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 18 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.Trader consensus centers on 70-75°F for San Francisco’s September 18 high, with 70-71°F the single most favored bin at 33% implied probability, reflecting the moderating influence of the marine layer and typical onshore westerly flow that caps daytime warming near the long-term average of 70.8°F. Recent model runs show highs in the upper 60s to mid-70s depending on the strength of the inversion and any breaks in coastal stratus, while historical September variability and current neutral ENSO conditions sustain the broad distribution. Key variables include wind direction and speed, which control advection of cooler Pacific air, plus the timing of any clearing that could allow brief warming above 75°F. Updated National Weather Service guidance and morning soundings ahead of the date remain the primary near-term catalysts.
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 18 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 16, 2026, 7:56 AM ET
Volume
$14End Date
Sep 18, 2026Market Opened
Sep 16, 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 18 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.Trader consensus centers on 70-75°F for San Francisco’s September 18 high, with 70-71°F the single most favored bin at 33% implied probability, reflecting the moderating influence of the marine layer and typical onshore westerly flow that caps daytime warming near the long-term average of 70.8°F. Recent model runs show highs in the upper 60s to mid-70s depending on the strength of the inversion and any breaks in coastal stratus, while historical September variability and current neutral ENSO conditions sustain the broad distribution. Key variables include wind direction and speed, which control advection of cooler Pacific air, plus the timing of any clearing that could allow brief warming above 75°F. Updated National Weather Service guidance and morning soundings ahead of the date remain the primary near-term catalysts.
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 18 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
$14End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 7:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=ksfoResolver
0x69c47De9D...Trader consensus centers on 70-75°F for San Francisco’s September 18 high, with 70-71°F the single most favored bin at 33% implied probability, reflecting the moderating influence of the marine layer and typical onshore westerly flow that caps daytime warming near the long-term average of 70.8°F. Recent model runs show highs in the upper 60s to mid-70s depending on the strength of the inversion and any breaks in coastal stratus, while historical September variability and current neutral ENSO conditions sustain the broad distribution. Key variables include wind direction and speed, which control advection of cooler Pacific air, plus the timing of any clearing that could allow brief warming above 75°F. Updated National Weather Service guidance and morning soundings ahead of the date remain the primary 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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