The Influence of Regional Storm Tracking and Teleconnections on Winter Precipitation in the Northeastern United States

Abstract

Secular changes in regional storm tracking are examined as physical mechanisms for observed teleconnections between the New England hydroclimate and four predictor variables: the Southern Oscillation Index, the North Atlantic Oscillation, the Pacific Decadal Oscillation, and regional sea-surface temperatures. The main modes of New England winter precipitation, snowfall, and cyclone variability are resolved using varimax rotated principal component analysis. The first rotated principal component of regional cyclone variability defines an out-of-phase relationship between marine versus continental cyclone activity and is statistically linked with the Southern Oscillation, the Pacific Decadal Oscillation, and precipitation in northern New England. Also, El Niño winters generally accompany a slight increase in southern New England precipitation. The second cyclone rotated principal component, defining an inverse relationship between cyclone occurrences along the East Coast and cyclone occurrences along the northern boundary of the Gulf Stream, is well correlated with regional precipitation and snowfall, demonstrating the significance of marine storm tracking as a control on New England winter hydroclimatic variability.Extreme North Atlantic Oscillation conditions are linked with distinct regional storm tracking patterns such that northwestern New England experiences fewer cyclones during negative North Atlantic Oscillation winter months. Statistical relationships between sea-surface temperatures and principal modes of regional cyclone occurrences are also noteworthy; however, more work is needed to assess the utility of sea-surface temperatures in the development of future seasonal forecasts. Also, confirming earlier findings, cool sea-surface temperature conditions are shown to accompany both drier conditions inland and greater winter snowfall totals in southern coastal regions.

Identification of large scale climate patterns affecting snow variability in the eastern United States

“…The Great Lakes region receives snowfall based on the lake effect, a phenomena caused by cold arctic air blowing over the relatively warm lakes, picking up moisture, then rising, causing the moisture to condense, and finally snowing over the downwind land (Heidorn, 1998;Niziol et al, 1995). Numerous studies have investigated wintertime precipitation in the northeast (Bradbury et al, 2002(Bradbury et al, , 2003Hartley, 1996;Hartley and Keables, 1998) as previously outlined, attributing variability to sea-surface temperatures, geopotential heights, and the NAO, allowing for colder temperatures, causing more precipitation to fall as snow. Contrastingly, TSF and NSD were very low (less than 5 days of snow and less than 200 mm of total season snowfall) south of Missouri, Kentucky, and Virginia, due to warmer seasonal temperatures.…”

“…Additionally, they found that lower 700 mb geopotential heights over the southeastern U.S. and Atlantic in wintertime, when preceded by a cold fall, tend to result in lower wintertime temperatures, creating more potential for precipitation to fall as snow. Bradbury et al (2003) linked New England snowfall variability to the NAO, ENSO, and the pacific decadal oscillation (PDO) via regional storm tracking patterns. They also identify a significant correlation between snowfall and regional SST anomalies, and suggest snowfall may also The previous section illustrates how past research has contributed to the understanding of snowfall variability over the eastern U.S. More investigation into the specific patterns, circulations, and areas of the globe that influence snowfall variability is necessary to make accurate predictions of seasonal snowfall for water managers and policy makers in this region.…”

Northeast US precipitation variability and North American climate teleconnections interpreted from late Holocene varved sediments

“…A more thorough understanding of regional hydroclimate variability and the associated linkages to known hemispheric/global patterns may assist in future predictive capabilities throughout North America. The patterns of atmospheric pressure centers described by these indices influence hydroclimatology by modulating midtropospheric circulation patterns and storm tracking (12). An important reconstruction of the position and amplitude of the vortex trough in the NE over the past millennium demonstrated that this dominant atmospheric feature has influenced precipitation variability over the late Holocene (13).…”

Manual synoptic climate classification for the east coast of New England (USA) with an application to PM2.5 concentration

“…This time period includes the El Niño event of late 1997/early 1998 and the 1999 La Niña event. However, the impacts of ENSO are minimal in New England (Ropelewski & Halpert 1987, Halpert & Ropelewski 1992, Bradbury et al 2003) and these occurrences should not affect the basic derivation of the synoptic classification. This use of daily maps should yield a reliable climatology, because the frequencies of synoptic-scale pressure patterns are largely unaffected by diurnal variability.…”