OK, now we’re getting to something a little more interesting. We’ve already covered isobars and isotherms, our next axis is the saturation mixing ratio. These are dashed lines that run from the south west of the Skew-T to the north east and represent the capacity to hold water vapor in the air at altitude. In other words, when moist air rises along the dry adiabatic (we’ll learn that next), the mixing ratio lines tell us at what pressure that dry air will be forced to condense and turn into the cloud base.
But first we have to get air into the atmosphere and that starts with the dry adiabatic.