Final answer:
Humidity is the weather factor that is a measurement of energy held within the air.
Step-by-step explanation:
The weather factor that is also a measurement of energy held within the air is humidity. Humidity refers to the amount of moisture or water vapor present in the air. It is an important factor in weather forecasting as it affects the heat index, which measures how hot it feels due to the combined effects of temperature and humidity.
High humidity can make the air feel warmer and more uncomfortable, while low humidity can make the air feel cooler and drier. The measurement of humidity is typically expressed as a percentage, with higher percentages indicating more moisture in the air.
Learn more about Weather Factors and Humidity