A large database is being created from icing flight programs completed by aircraft manufacturers for certification and by the NASA-Glenn Research Center for basic research. Although not yet complete, this database already provides an excellent opportunity to study aircraft icing conditions sampled in a wide variety of environments across eastern Canada and most of the United States, including Alaska. In this study, the focus is a comparison of conditions found within boundary-layer stratocumulus icing clouds over the Great Lakes, Pacific Northwest and Alaskan Interior. The clouds will be characterized in terms of temperature, liquid water content, median volumetric diameter, and drop concentration. Critical factors driving these parameters will be discussed.