Enter the boundary layer air density and the boundary layer vertical outflow into the Calculator. The calculator will evaluate the Pressure Tendency. 

Pressure Tendency Formula

PT = -g*pbl*Wbl

Variables:

  • PT is the Pressure Tendency ()
  • pbl is the boundary layer air density
  • Wbl is the boundary layer vertical outflow

To calculate Pressure Tendency, multiply the boundary layer air density by the boundary layer vertical outflow, then multiply by -9.8m/s^2.

How to Calculate Pressure Tendency?

The following steps outline how to calculate the Pressure Tendency.


  1. First, determine the boundary layer air density. 
  2. Next, determine the boundary layer vertical outflow. 
  3. Next, gather the formula from above = PT = -g*pbl*Wbl.
  4. Finally, calculate the Pressure Tendency.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

boundary layer air density = 6.54

boundary layer vertical outflow = 1.234

Frequently Asked Questions

What is boundary layer air density?

Boundary layer air density refers to the mass per unit volume of air within the atmospheric boundary layer, the part of the atmosphere directly influenced by the earth’s surface. It can vary due to temperature, humidity, and altitude changes.

How does vertical outflow affect weather patterns?

Vertical outflow in the boundary layer can significantly impact weather patterns by influencing the distribution of heat and moisture. This can lead to the formation of clouds, changes in precipitation patterns, and the development of storms.

Why is the gravitational acceleration (-9.8 m/s^2) used in the Pressure Tendency Formula?

The gravitational acceleration constant (-9.8 m/s^2) is used in the Pressure Tendency Formula to account for the force of gravity acting on the air’s mass within the boundary layer. This helps in calculating the net force that influences the pressure tendency.

Can the Pressure Tendency Formula be used for forecasting weather?

Yes, the Pressure Tendency Formula can be a valuable tool in weather forecasting. By understanding how the pressure within the boundary layer is likely to change, meteorologists can make predictions about weather conditions, such as the development of high or low-pressure systems, which influence weather patterns.