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Convective Scale Interaction is a term given to the process in which a collapsing storm produces precipitation and downdrafts, called an outflow boundary, or gust front. The downdraft air fans out below the cloud base undercutting relatively warmer, and often, more moist air. The moist air then is lifted above the gust front into an often unstable atmosphere which causes new severe storms which can grow rapidly to maturity, collapse and produce its own outflows repeating the whole process. Single outflow boundaries have been known to be strong enough to travel more than a hundred miles from its parent storm. Satellite views of clouds forming along' these moving gust fronts often show the clouds align themselves into a semi-circular, fan-shaped orientation called "arc-clouds" which can develop into large, severe convective storm systems. Single storms, multiple storms and supercells all have been identified as forming along these gust fronts. Research in the southeastern part of the U.S.A., several years ago, estimated 60%-75% of the storms existing in late afternoon on a typical storm day were caused by scale interaction. Two, or more, colliding gust fronts frequently create extremely severe storms, but are often short-lived. Severe turbulence is frequently found in gust front air between the parent storm and the leading edge of the gust front. Convective Scale interaction as described here frequently occurs on the WKWMP and, when identified on radar or reported by pilots,. its occurrence and direction of movement is monitored carefully for subsequent new storm development above it. Also, it has been observed that severe new storm growth often develops in weak, old non-hail bearing precipitation areas, which are undercut by gust fronts. Satellite imagery can also give advance. warning about subsequent new storm development potential which can't be seen immediat~ly on radar or visually by pilots. Under some conditions rainfall augmentation over large areas have been produced by seeding atop the leading edge of a gust front as air is lifted over it causing weak cumuliform clouds to form. Updrafts found above gust fronts have wide variability---from 100 - 200 feet per minute to a more normal 1000 - 1500 feet per minute, or more. If this particular condition occurs at night with little threat of hail developing from new storm growth and updrafts are weak, seeding to increase rainfall has appeared to be highly productive over large areas. In such cases the cloud's microphysical characteristics are attempted to be altered by seeding. It's likely under these conditions the dynamic effect is reduced, whereas, the "static" seeding effect is bein'g achieved. It also appears likely, if hygroscopic flares are used in such instances, the rain stimulation effect might be even better as heavier rainfall falls from the same clouds. There is another form of cloud system which has important seeding potential for producing precipitation in Kansas: the 10