National Weather Service forecasts project a high near 70°F for San Francisco on May 19 under clear skies and light winds, driving the 99.1% market-implied probability for 66°F or higher. Mid-May climatological normals at San Francisco International Airport average 68°F, and recent model consensus shows minimal cooling from onshore flow or marine layer intrusion. Historical data indicate that persistent high-pressure ridging supports above-normal maxima in this range, with low precipitation risk reinforcing stable conditions. A late-developing coastal fog bank or stronger northwest breeze could limit readings to the low 60s, though current guidance assigns low likelihood to such shifts before resolution.
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 May 19?
Highest temperature in San Francisco on May 19?
66°F or higher 99.4%
56-57°F <1%
58-59°F <1%
54-55°F <1%
NEW
$33,687 Vol.
NEW
$33,687 Vol.
May 19, 2026
47°F or below
<1%
48-49°F
<1%
50-51°F
<1%
52-53°F
<1%
54-55°F
<1%
56-57°F
<1%
58-59°F
<1%
60-61°F
<1%
62-63°F
<1%
64-65°F
<1%
66°F or higher
99%
66°F or higher 99.4%
56-57°F <1%
58-59°F <1%
54-55°F <1%
NEW
$33,687 Vol.
NEW
$33,687 Vol.
May 19, 2026
47°F or below
$697 Vol.
<1%
48-49°F
$616 Vol.
<1%
50-51°F
$616 Vol.
<1%
52-53°F
$3,968 Vol.
<1%
54-55°F
$4,823 Vol.
<1%
56-57°F
$4,770 Vol.
<1%
58-59°F
$4,248 Vol.
<1%
60-61°F
$4,112 Vol.
<1%
62-63°F
$1,277 Vol.
<1%
64-65°F
$3,818 Vol.
<1%
66°F or higher
$4,759 Vol.
99%
This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.National Weather Service forecasts project a high near 70°F for San Francisco on May 19 under clear skies and light winds, driving the 99.1% market-implied probability for 66°F or higher. Mid-May climatological normals at San Francisco International Airport average 68°F, and recent model consensus shows minimal cooling from onshore flow or marine layer intrusion. Historical data indicate that persistent high-pressure ridging supports above-normal maxima in this range, with low precipitation risk reinforcing stable conditions. A late-developing coastal fog bank or stronger northwest breeze could limit readings to the low 60s, though current guidance assigns low likelihood to such shifts before resolution.
This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: May 17, 2026, 12:05 AM ET
Volume
$33,687End Date
May 19, 2026Market Opened
May 17, 2026, 12:05 AM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFOThis market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.National Weather Service forecasts project a high near 70°F for San Francisco on May 19 under clear skies and light winds, driving the 99.1% market-implied probability for 66°F or higher. Mid-May climatological normals at San Francisco International Airport average 68°F, and recent model consensus shows minimal cooling from onshore flow or marine layer intrusion. Historical data indicate that persistent high-pressure ridging supports above-normal maxima in this range, with low precipitation risk reinforcing stable conditions. A late-developing coastal fog bank or stronger northwest breeze could limit readings to the low 60s, though current guidance assigns low likelihood to such shifts before resolution.
This market will resolve to the temperature range that contains the highest temperature recorded at the San Francisco International Airport Station in degrees Fahrenheit on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the San Francisco International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFO.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$33,687End Date
May 19, 2026Market Opened
May 17, 2026, 12:05 AM ETResolution Source
https://www.wunderground.com/history/daily/us/ca/san-francisco/KSFONational Weather Service forecasts project a high near 70°F for San Francisco on May 19 under clear skies and light winds, driving the 99.1% market-implied probability for 66°F or higher. Mid-May climatological normals at San Francisco International Airport average 68°F, and recent model consensus shows minimal cooling from onshore flow or marine layer intrusion. Historical data indicate that persistent high-pressure ridging supports above-normal maxima in this range, with low precipitation risk reinforcing stable conditions. A late-developing coastal fog bank or stronger northwest breeze could limit readings to the low 60s, though current guidance assigns low likelihood to such shifts 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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