Now consider the same school door on an October afternoon.

The air is hot, and the air holds only a little water vapor.

Is the humidity high? No, the humidity is low, and the air feels dry.

Now consider the same door on a December afternoon. The air is cool, and the air holds only a little water vapor.

Is the humidity high? No, the humidity is low again.

Now consider the same door on a January morning.

Fog hangs over the field, the grass is wet, and the air is cool.

The same door on a cool, damp January morning.

The cool air holds a lot of water vapor.

Is the humidity high? Yes, the humidity is high, and the air feels damp.

Two cool days at the door: a lot of water vapor on the left, a little on the right. Only the water vapor differs.

Four days at the school door. The water vapor decides the humidity, not how warm the air is.

On the two hot days, the humidity was high on one day and low on the other.

On the two cool days, the humidity was low on one day and high on the other.

So, when Mira said humid is just another word for hot, she was not right. Humid is not another word for hot.

Humid air is air that holds a lot of water vapor, and cool air can hold a lot of water vapor too.