Is it sultry because of the high humidity?

The sultry weather is caused by high humidity.

In a hot environment, the higher the humidity, the hotter the feeling and the stronger the ability to wet the air. This is because the higher the temperature, the faster the water vapor molecules move, and more water vapor can be contained in the air.

Relative humidity is often used in weather forecast, which reflects the possibility of rain and fog. In hot weather, high relative humidity will make people feel hotter, so the heat index can be calculated. And when it rains, the air humidity is very high. Humidity is an important data for determining evaporation and transpiration in meteorology and hydrology, and plays a decisive role in the production of different climatic zones.