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VI. RAINFALL DISTRIBUTION As in other Final Reports, we again show Palmer Long-Term Drought Severity Index for soil moisture conditions for the country during the period roughly paralleling our weather modification program---May through mid-September. The index is produced by the NOAA/USDA Joint Weather Facility in Washington, D.C. every second week in the periodical, "Weeklv Weather and Crop Bulletin". The index is not prone to short-term moisture changes and normally takes periods of weeks or months to change, not days. The index is developed from official measurements made at second-order weather observing sites, usually 30 - 40 miles apart in our area. However, the areas categorized generally do tend to exhibit moisture trends more closely to the category shown than not. Figure 5 shows the change during in 1993---in which there was virtually no long-term soil moisture change during the season for most of the WKWM target area, except near the Kansas-Colorado state line. We remained relatively "Moist" throughout the season. Of perhaps more interest this year was the Palmer Short-Term Drought Severity Index, a measure of the more rapid response to shorter period rainfall, or lack of it, virtually week to week. Figure 6 shows how that index changed this season. Beginning May 1st the wet areas were shown along the Mississippi River' in Minnesota, Wisconsin, Iowa and Illinois. By early July a moist tongue was developing southwestward from Iowa across northern Missouri and into northeastern and northcentral Kansas, then, by July's end most of the north half of Kansas was relatively wet. In fact flooding had occurred on many streams and rivers not too far north-east of the WKWM target area. That pocket of wet soil conditions moved further west into the northwestern and westcentral Kansas in Augus"C. When the WKWM season ended in September, the really wet area was confined mostly "Co the northwest part of the s"Cate. 31