The characteristics of each individual storm can have a significant impact on hydrological processes such as stream flow and soil erosion by water. These characteristics vary greatly by season and geographic region across the U.S. This paper will describe the spatial pattern across the U.S. of mean storm characteristics. for each season and the year. The storm characteristics described include storm total precipitation, storm duration, storm precipitation intensity, energy of precipitation during the storm, the 30-minute maximum precipitation intensity, total storm erosivity, the maximum 15-minute precipitation intensity, the ratio of the maximum 15-minute intensity to the mean storm intensity, and the rainfall total in the largest shower. The storm characteristics were developed using the15-minute rainfall records (NCDC TD-3260) from 1971 to 1999. The analysis includes multi-day storms, and more than one storm may occur in a single day. A storm period is defined as a period of rain from the first shower until the last shower is separated from the next shower in a day or consecutive day by six or more hours. The analysis will include a discussion of all storms regardless of the amount of rainfall, and of storms that receive more than 12.7 mm of rain or have a 15-minute intensity greater than 24 mm hr-1.