An objective method has been developed for determining the occurrence and altitude of tall convective clouds for the purpose of construction of a global climatology of such clouds. The particular computer program selected is the version that produced maximum cloud-top estimates in closest agreement with highest radar precipitation echoes for a three-year period at Miami, Fla., Lake Charles, La., New York, N.Y., and Oklahoma City, Okla. A day-by-day comparison of radar echoes and computed cloud tops reveals such numerous and sufficiently large discrepancies that the computerized parcel method does not appear satisfactory for providing a climatology of convective clouds above 40,000 ft. (Author).