What about the temps from the rest of the city ?
Airport’s are used as the official weather data for a region because of the open spaces of the airport, lack of trees and lack of dense buildings wish block airflow and also radiate heat from their sun baked walls. The city was likely hotter due to the urban heat island effect. While it might seem that the runways and taxi aprons would be a heat island the total land area covered by improved surfaces the official term for them vs grass and vegetation or unimproved surfaces is such that an airport is less of a heat island than the typical urban scape. Accurate temps for aircraft operations is why there is always a NWS sensor stack on site at every major airport. Air density is a function of temperature, humidity and pressure. Accurate data is critical for 100 tonne objects to get airborne the FAA a s NWS doesn’t mess around with that data peoples lives depend on it. This is why official weather data for a region from the airport’s and has been that way for most of the 20th century and into the 21st. The first thing us pilots lock at before we fuel and weight calc is METAR data. Get it wrong and your dead.