Abstract
Examination of radar records shows that snow trails frequently occur around the tops of showers. Evidence has been sought that showers are occasionally initiated by the seeding of supercooled cumulus clouds by snow. Certain observed radar patterns suggest strongly that showers were produced in this manner. As a check, plan diagrams with height contours have been synthesized and used to organize vertical sections obtained on different bearings. The constructed plan diagrams show showers occurring in regions of snow trails more frequently than elsewhere.
