Synoptic Typing of Multiduration, Heavy Precipitation Records in the Northeastern United States: 1895-2017

Much of the previous analyses of the total and heavy precipitation trends across the Northeastern US (hereafter Northeast) used daily precipitation totals over relatively short periods of record, which do not capture the full range of climate variability and change. Less is understood about the characteristics of long-term changes and synoptic patterns in longer-duration (weekly to monthly) heavy precipitation events across the Northeast. In this study, we utilize a multi-duration (1, 2, 3, 7, 14, and 30 days), multi-return interval (2, 5, 10, and 50 years) precipitation dataset to explore changes in various types of precipitation events across the Northeast from 1895 to 2017. We then apply Rotated Principal Component Analysis to daily 850-hPa geopotential height patterns associated with these precipitation events to identify the main synoptic drivers associated with the structure of heavy precipitation events over time.