How closely a nearby Wunderground backyard station, and the official live local feed where one exists (JMA for Tokyo, MetService for Wellington, MSS for Singapore, ...), track the airport METAR that Polymarket temperature markets resolve on. Compared on each city's local-day high.
Highest "Temp" reading of the day on weather.gov/wrh/timeseries (the airport METAR, whole °C or °F). This is what the PWS is compared against.
Only if NOAA has no data for the date by 11:59 PM ET the next day. Then the Wunderground Daily Observations table decides.
If neither source has data by that deadline, the market resolves to the lowest bracket.
Taipei and Lagos resolve on Wunderground directly, with no NOAA step. Hong Kong resolves on the Observatory's final daily max to 0.1°C, no Wunderground fallback, with a 7-day window and revisions ignored.