How and why does fog form? A meteorologist explains ?

Muggy mornings in South Central Texas can often consist of dew, a big can of hairspray, and at times another meteorological phenomena: fog.

We run into fog on the morning commute or drive to school, which can often slow us down.

There are several different types of fog, but how exactly does fog form?

To understand the answer to that question, we first need to talk about the air temperature and the dew point temperature.

We all know the air temperature, which is essentially how hot or cold it is outside.

The dew point temperature, however, is another weather parameter that meteorologists use to represent the temperature that the air must cool down to in order to become saturated.

Higher dewpoints mean that the air is muggy and humid, while lower dewpoints mean that the air is drier and more comfortable.

As the air temperature cools down over the course of a muggy night, it starts to approach the dewpoint temperature.

The closer those two numbers are together, the more saturated the air around us becomes.

Similar to how a cloud forms above our heads, fog then starts to develop under these saturated conditions as water vapor condenses onto small particles in the air.

The result: reduced visibility out on the roadways!

There are several safety measures that are important to follow when driving in the fog:

Slow down your speed and allow extra time to get to your destination
Use your low-beam headlights when driving

Leave plenty of distance between you and the vehicle in front of you in case of a sudden stop

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