What is the standard day temperature in Fahrenheit?

The standard day temperature, often used in aviation and meteorology, is defined as 59°F. This temperature is significant because it is a baseline for assessing atmospheric conditions and performance calculations, such as aircraft performance, density altitude, and pressure altitude.

In aviation contexts, this standard temperature is critical for pilots to understand as it allows for consistent references when dealing with various environmental factors affecting flight parameters. While other temperatures listed may represent different standards in other fields or contexts, 59°F remains the recognized standard for the purposes of weather-related calculations and assessments in aviation.