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cloud properties reasonably well when the sounding is taken close to the time of cloud development. The average observed cloud radius in these cases was approximately 2.7 km. Examination of the 1200 G.m.t. early morning sounding (table 3) showed that the correlations were poorer and errors were much greater than the early afternoon results, which were closest to aircraft observations. This small sample of verification statistics tends to support the need for local afternoon soundings near developing clouds in space and time for best model simulations. Note that 13 of the 26 soundings had errors in cloud-top height within 500 m of that observed. Observed cloud-top heights ranged from 5.3 to 13.7 km; whereas, model-predicted cloud-top heights ranged from 3.3 to 13.6 km for this set of 3-km cloud radius cases. The average observed cloud-top height was 8.65 km; however, the average cloud-top height predicted by the model varied as a function of input cloud radius. 1 This comparison between model and aircraft observations is not intended to rigorously verify the model. The model predicts a spectra of clouds depending upon the initial updraft radius. Caution must be used in interpretation of model results due to the sensitivity of the model to "updraft radius" and cloud-base height. These properties must be care- fully matched with those of observed clouds in comparison of individual clouds (Warner, 1970). This comparison simply indicates that the model is able to diagnose basic cloud properties such as base height and cloud top which can be used to broadly classify the potential for convective develop- ment from a local rawinsonde. Hence, the model is viewed as a more comprehensive Showalter (1953) or Totals Totals Index (Miller, 1972) of convective development to examine the natural variability of thermodynamics 16