Value range of a geophysical parameter (temperature, pressure, humidity,..) at some point-like location and at a specific time. The truth value of this statement is not considered here, value may be speculative (forecast). The main intention for objects of this type is to represent forecast parameter value ranges on a map.
Preferred font size in points for the label can specified with the preferredRenderingSize property by using "pt" as the uom (Unit Of Measure) attribute of "value".