Examination of simultaneous radio-soundings at Perth and Kalgoorlie, when a “meridional front” lies between the stations, shows that half the disturbances are non-frontal in nature. A sub-division of "frontal" and "non-frontal” cases is made, and some considerations on the structure of each type are advanced. A study of the associated weather and upper wind observations, and of the synoptic situation, also shows some important differences between the types, although it is difficult to distinguish between them on surface weather observations alone.
AJ TROUP (Sat,) studied this question.