In this activity you will interact with numerical model output from the North American Mesoscale (NAM) model to explore the concepts of a Skew-T log p diagram.

By the end of this module you should be able to:


Every morning, weather balloons are launched from different rawinsonde sites around the country at the same time. This is done to get a vertical profile of the atmosphere which can then be plotted up into a sounding on a chart called a Skew-T Log-P diagram. Temperature, dewpoint, and the winds (speed and direction) are plotted versus pressure/height to give details on the vertical structure of the atmosphere. “Soundings” are a snapshot of the vertical composition of the atmosphere at a certain time, usually displayed on a Skew-T Log-P diagram. The data that is gained from them is essential to run synoptic and mesoscale forecast models, like the NAM. This module will help you understand the importance of soundings in meteorology through the following sections:

1) How to Read a Skew-T

2) Determining Meteorological Parameters from a Sounding

3) Stability

4) Inversions

5) Questions


Loading the IDV Bundle
Click on the link to the bundle skew-t.jnlp. Two main windows should appear; the Display Window and the Data Selector Window. Various Parameter Windows will also appear. Once the bundle is loaded, proceed to the next section.

NOTE: In some instances, the IDV bundle loads properly but appears to be frozen (Bundle will not loop and parameters will not show up when checked). If this occurs, go to “File”, then “New” > “Display Window” >“Map Display” > “One Pane”. A new display window should appear and the bundle will now be fully functional.




LEAD-to-Learn Modules