Previous work has identified a significant upward trend in the frequency of heavy precipitation events in the United States for the period 1931-1996. The present study examined the circulation patterns associated with such events, including their trends and variability. The analysis of circulation patterns focused on periods when large numbers of stations experienced a heavy precipitation event from the same storm system. For each of the nine climate regions of the U.S., we identified the 20 periods for 1946-1994 with the largest event area. The average 500 hPa standardized height departures averaged for these 20 periods exhibit a high amplitude wave pattern with negative height departures directly upstream of the region and positive height departures directly downstream of the region with a planetary wave number of five. The departure centers were used to construct a circulation index for each region. For the period 1946-1994, the trend in the annual circulation index is in the same direction as the trend in the annual event area for the Northeast, East North Central, Southwest, and West regions. The monthly event areas for the East North Central, Central and Northwest regions are significantly negatively correlated with the Pacific-North America pattern. The monthly event areas for the winter months (November-March) for the West region are statistically significantly correlated with the monthly Southern Oscillation Index