Will London hit 21°C on Tuesday, Oct 13, 2026?

Yes

<think> Okay, let's tackle this. The market question is whether London hit 21°C on October 13, 2026. The resolution criteria specify that it's based on the daily maximum at 2 meters above ground in London, UK, during the specified UTC window. Resolver 1 says "No," citing Heathrow and Central London data with maxima below 21°C: 19.9 and 20.4. Resolver 2 says "Yes," pointing to SYNOP data from Heathrow showing 21.2°C and Weather Underground at 21.1°C. Both resolvers use credible sources, but they reference different data. I need to check which sources align with the criteria. The criteria mention "official or widely recognised" stations like Heathrow. SYNOP data from Heathrow (WMO 03772, EGLL) is an official observation. The 10212 group decodes to 21.2°C at 13:20 UTC, which is within the window. Weather Underground also reports 70°F (21.1°C) for the same day. Resolver 1 might be using gridded data (like Open-Meteo) which can be less precise than station data. The criteria allow official station observations, so Heathrow's direct reading should take precedence. Therefore, Resolver 2's evidence supports the "Yes" answer. </think> ANSWER: Yes

Resolution criteria: - "Yes": Wins if the recorded daily maximum air temperature at 2 metres above ground for London, UK on 2026-10-13 (strictly after 2026-10-12T23:00:00Z and at or before 2026-10-13T23:00:00Z) is at or above 21°C according to credible meteorological sources. - "No": Wins if the recorded daily maximum air temperature at 2 metres above ground for London, UK on 2026-10-13 (strictly after 2026-10-12T23:00:00Z and at or before 2026-10-13T23:00:00Z) remains strictly below 21°C according to credible meteorological sources. Clarifications: - "Hit 21°C" means the daily maximum temperature (Tmax) at 2 metres above ground reaches or exceeds 21.0°C at any point during the UTC window strictly after 2026-10-12T23:00:00Z and at or before 2026-10-13T23:00:00Z, as recorded by official or widely recognised meteorological observation networks covering Greater London (e.g. Heathrow/LHR, London Weather Centre, or equivalent official station).