i think you are refering to condensate (c6+). which is more or less stable at stock tank conditions. lpg (primarily propane) is stored in a pressurized vessel. ngl refers to the whole range of intermediate components (c2 - c6) which can be liquified by cooling and are components of gasoline and chemical feedstocks. lng is liquified methane.
and with all of these designations, it is important to remember that they arent a pure single component. condensate will contain a small fraction of methane for example.

methane b.p. -161 ºC, ethane b.p. -88 ºC , propane b.p. -42.1 ºC, butane b.p. -0.5 ºC, pentane b.p. 35-36 ºC and hexanes 68-70 ºC