Raindrop Size Distributions (RSDs) samples from 17 flight missions though 6 hurricanes collected by Precipitation Imaging Probe (PIP) during National Oceanic and Atmospheric Administration’s hurricane field program in 2020 are used to study gamma fits of the RSDs in hurricanes. The method of moment (MM) is adopted for solving for the three parameters in gamma distribution. The results show that the usage of lower (higher) moments produces large biases for integral rain variables (IRV) of higher (lower) moments. These biases can be alleviated by extracting the best fits from five groups that use increasing higher orders of moments for MM. An intercept (N0)— slope (λ) relation identified from the fitted gamma distributions captures 92% of the variance of the data, where the majority of remaining 8% can be further captured by including the impact of liquid water content (LWC), as shown in the results from a random forest regression model.