There is a great discussion thread going on over on the New Zealand Weather & Climate forum
here.
One of the weather guys wrote about Skew-T and plotting variables - immedately I did a search on google and found some great a couple of resources. Often the weather guys, like John, Brian, spwill, nzstorm, Vertigo, TT, jamie h, David, Richard, nev, Myself, Snoopy, Andrew, Michael and the Canty weather guys (actually all of them ) will use the same repetitive weather terminology in their posts - words like inversion, LI, scud, DP's, cape, 500mb

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which is very important.
So, to help understand this better... I am going to post a few links to resources that I think are helpful and also that a few other weather newbies may find helpful also.
What is a Skew-T?
A thermodynamic diagram is a chart on which pressure, density, temperature and water vapor are plotted for a point on the Earth up through the atmosphere. By having temperature against pressure, one can get a feel for many variables at a glance without performing lengthy calculations. The data is gathered by an instrument package attached to a balloon called a radiosonde launched from hundreds of sites around the world.
One specific type of thermodynamic diagram is a skew-T log-p, or skew-t, that tilts the lines of constant temperature (isotherms) and compresses the pressure scale logarithmicly.
How to read a Skew-TWhen you first look at a Skew-T, what do you see? There's nothing but a bunch of lines, right? Here is a quick explanation of what all those lines mean.
Isobars (D) -- Lines of equal pressure. Solid brown lines that run horizontally from left to right and are labeled on the left side of the diagram. Pressure is given in increments of 100 mb and ranges from 1050 mb to 100 mb. Spacing between the isobars increases in the vertical because of the log scale that is used to represent pressure.
Isotherms -- Lines of equal temperature. Straight, solid brown lines that slope from the bottom left to the upper right (thus the name skew) across the diagram. Increments are per degree and are labeled for every 5 degrees in units of Celsius. They are labeled at the bottom of the diagram with corresponding temperatures in Fahrenheit.
Dry Adiabats (E) -- Slightly curved, solid brown lines that slant from lower right to upper left. They are labeled every 10 degrees Celsius and indicate the rate of change of temperature in an air parcel of dry air rising or descending adiabatically.
Saturation Adiabats (F) -- Slightly curved, solid green lines sloping from lower right to upper left. They are labeled every 2 degrees Celsius and indicate the rate of change of temperature in a saturated air parcel as it rises pseudo-adiabatically. They become parallel to the dry Adiabats at the top of the chart because of the very low moisture content at those levels and stop at 200 mb.
Saturation Mixing Ratio Lines (C) -- These are the dashed green, slightly curved lines that slope from the lower left to the upper right that represent lines of equal mixing ratio. They are labeled on the bottom of the diagram in grams per kilogram of water vapor. They extend only to 200 mb and the spacing between them decreases as their values increase.
Temperature Curve (B) -- This is the plot of the temperature measurements that were taken from the rawinsonde as it was increasing in height. This curve will always be to the right of the dewpoint curve as you are facing a Skew-T. It is usually drawn in red but can be other colors.
Dewpoint Curve (A) -- This is the plot of the dewpoint measurements increasing with height. This curve will always be to the left of the temperature curve as you are facing a Skew-T. It is usually drawn in green but can be other colors.
edit reasons: including Michael, cant forget Michael with his lively SW winds, Gale Force, pine needles and beep bop - famous on Michael weather blog reports

AWE some!