TAMPA, Fla. — Barometers are very important when it comes to weather forecasting. A barometer can measure the pressure of the atmosphere and it can tell us whether or not the air pressure is rising or falling. A meteorologist can use this information to determine whether a storm is coming or leaving.

The weight of the air around us is a lot! Did you know the average person has more than 2,000 pounds of air resting on their heads? That’s more than the weight of an entire giraffe! So why aren’t we crushed? Thank goodness for strong vertebrae!

The air pressure changes all the time depending on if a storm is approaching or leaving. Let’s begin with defining air pressure. It is the weight (force) of the Earth’s atmosphere pressing down on any object on the Earth’s surface.

There are many units to describe air pressure. The two most common metric units meteorologist use are “Inches of Mercury (Hg)” or “millibars (mb).” You may hear meteorologist refer to these units when describing the strength of a hurricane.

There is a cool tool used to measure air pressure and it is called a barometer. It is one of the original tools used by meteorologists and it was invented way back in 1643. That was a long time ago, before the birth of the United States!

Barometers can detect if the air pressure is rising or sinking. Meteorologist use this information to tell whether a storm is approaching or leaving. Nice weather is associated with high pressure. When the air pressure rises, a meteorologist can generally expect improving weather or nice weather. Low pressure is generally associated with stormy weather. If the air pressure is decreasing, it might mean a storm is approaching.

Therefore, it is very important for meteorologists to track the change of air pressure all over the world. This helps meteorologists know where storms are heading.