East Coast Winter Storms (ECWS) can have tremendous impacts throughout the eastern regions of the United States. Forecasting influences from these storms, particularly long range and due to seasonal variations, is extremely challenging. Using a previously compiled climatology of ECWS events, an ECWS precipitation climatology is developed for the eastern United States from 1951-1952 to 2005-2006, using an automated procedure. This climatology consists of the percentage of snowfall and precipitation from ECWS, on average per snow year. The exclusion of non-ECWS snowfall and precipitation during ECWS events is accomplished by utilizing a precipitation gradient line, a pressure gradient line, and the presence of a non-ECWS, if applicable. The issue of excluding lake effect snow (LES) is also addressed. This same climatology is developed for rapidly deepening ECWS, termed ?bombs? by previous studies. A sensitivity analysis of the ECWS precipitation climatology is investigated considering the following scenarios during an event: the absence of any process for identifying ECWS snowfall or precipitation, the absence of any process for classifying LES, and a comparison of two methods for classification of LES. The ECWS precipitation climatology is then analyzed for relationships to ENSO phases and ECWS frequency, by snow year, and for the presence of time dependent trends. The climatology reveals the highest percentages of snowfall from ECWS, on average per snow year, are located in a swath from southeastern Mississippi to northeastern Georgia, with percentages typically ranging from 65 to 80%. While the highest percentages of precipitation from ECWS, on average per snow year, are located along the east coast from the Delaware and Maryland border, northward to Maine, with percentages generally from 20 to 25%. No time dependent trends are evident for the amount of precipitation or snowfall from ECWS, nor are they evident for the percentage of precipitation or snowfall from ECWS. In northern New England and along the urban corridor of the Northeast, including the cities of Washington DC, Baltimore, Philadelphia, New York and Boston, El Ni?o years signal above average precipitation and snowfall amounts from ECWS, in addition to above average percentage of precipitation and snowfall from ECWS. While in portions of the Appalachian Mountains and the Southeast, La Ni?a years signal a below average percentage of precipitation from ECWS. Finally, high (low) ECWS occurrence snow years, or active (inactive) seasons, signal above (below) average ECWS precipitation amounts and percentage of precipitation from ECWS. Specifically, for the large metropolitan centers of the Northeast, high ECWS occurrence snow years, or active seasons, signal above average ECWS precipitation and snowfall amounts, above average total precipitation and snowfall amounts, and above average percentage of precipitation and snowfall from ECWS. In contrast, low ECWS occurrence snow years, or inactive seasons, signal below average ECWS precipitation and snowfall amounts, below average total precipitation amounts, and below average percentage of precipitation from ECWS. ii