Recent forecast models indicate a strong southwesterly wind shift arriving overnight, potentially advecting cooler polar maritime air into the region and enhancing nocturnal radiative cooling under clearing skies. This setup creates substantial uncertainty around the minimum, with some ensemble members projecting lows near or below 7°C while others retain milder conditions near 17°C or higher due to variable cloud cover and wind strength. Key differentiators include the precise timing of the frontal passage, surface pressure gradients driving the cold-air outbreak, and local urban heat-island effects in Buenos Aires. Traders are closely monitoring updated runs from global models ahead of the overnight period, as small shifts in these variables can swing the outcome across the tightly contested probability bands.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in Buenos Aires on September 21?
7°C or below 95%
17°C or higher 93%
10°C 40%
8°C 24%
7°C or below
95%
8°C
24%
9°C
23%
10°C
40%
11°C
19%
12°C
19%
13°C
11%
14°C
13%
15°C
13%
16°C
13%
17°C or higher
93%
7°C or below 95%
17°C or higher 93%
10°C 40%
8°C 24%
7°C or below
95%
8°C
24%
9°C
23%
10°C
40%
11°C
19%
12°C
19%
13°C
11%
14°C
13%
15°C
13%
16°C
13%
17°C or higher
93%
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=saez
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 Metric Units" button until the relevant table displays °C.
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 Celsius (eg, 9°C). 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 19, 2026, 8:29 AM ET
Resolution Source
https://www.weather.gov/wrh/timeseries?site=saezResolver
0x69c47De9D...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=saez
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 Metric Units" button until the relevant table displays °C.
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 Celsius (eg, 9°C). 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.
Resolution Source
https://www.weather.gov/wrh/timeseries?site=saezResolver
0x69c47De9D...Recent forecast models indicate a strong southwesterly wind shift arriving overnight, potentially advecting cooler polar maritime air into the region and enhancing nocturnal radiative cooling under clearing skies. This setup creates substantial uncertainty around the minimum, with some ensemble members projecting lows near or below 7°C while others retain milder conditions near 17°C or higher due to variable cloud cover and wind strength. Key differentiators include the precise timing of the frontal passage, surface pressure gradients driving the cold-air outbreak, and local urban heat-island effects in Buenos Aires. Traders are closely monitoring updated runs from global models ahead of the overnight period, as small shifts in these variables can swing the outcome across the tightly contested probability bands.
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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