Definitions for "Precipitable water"
The total mass of water in a vertical atmospheric column of unit area, or its height if condensed in liquid form.
The total atmospheric water vapor contained in a vertical column of unit cross sectional area that would stand if completely condensed and collected in a vessel.
The depth, or amount, of water that would result if all of the water vapor in the atmosphere above a certain location were condensed into liquid water. NWS graphics show precipitable water in terms of inches and percentage of normal (for the given day).