Data obtained in a thunderstorm with a vertically pointing Doppler radar areanalyzed to find the size distribution of raindrops at heights below the OC level. Drop-size distributions were computed using the updraft U r deduced by Rogers' method and two other updrafts, namely, U r -1 and U r+1 m sec-1. It is found that the drop-size data at all the heights may be well represented by the exponential equation, N(D)=N0 exp(-A D), in which N(D)AD is the concentration of drops in the diameter range D to D+AD, No=0.07R0.37 (cm-4), and A=38R-0.14 (cm-1), R being the rainfall rate (mm hr-1). For R>~3 mm hr-1, the distribution is steeper and No is greater as compared to the Marshall-Palmer distribution. For radar reflectivity factors Z in the range 1-10 5 mm6 m-3, the relationship between the mean Doppler velocity and Z for the distribution agrees with that given by Rogers to within 1 m sec-1. The following equations have been found between the water content M, median volume diameterDo, radar reflectivity factor Z, and the rainfall rate R:M=0.052R 0.94 (gm m-3), Do=0.13R 0.14 (mm),Z=300R 1.35 (mm6m-3).