Changing Characteristics of Precipitation and Drought in the Northeast U.S.

The National Drought Mitigation Center (NDMC) partnered with the U.S. Department of Agriculture’s Northeast Climate Hub to investigate changing characteristics of drought and precipitation (especially winter precipitation) in the northeast U.S. to help address gaps in current research. 

The goal of this analysis was to evaluate trends in recent observed data pertaining to drought, precipitation, and snow in the Northeast. To accomplish this, researchers performed a literature review and acquired hydroclimatic data, including precipitation data from NDMC’s Drought Risk Atlas and snow depth data from the Applied Climate Information System (ACIS). 

Key takeaways from the research:

• The results from this analysis support the observed and expected increase in winter and spring precipitation and heavy precipitation events in the Northeast. 
• No clear signals emerged for recent changes in the number of dry periods in the Northeast. Future work could examine the maximum lengths of dry periods each year, rather than the number of periods that meet a certain threshold. 
• Spring and annual snowfall has decreased across most of the Northeast, especially in the Appalachian regions of Pennsylvania, Maryland, and West Virginia. It is possible that some increase in snowfall has occurred in northeastern parts of New England. 
• Days with non-zero snow depth in February appear to be decreasing overall in the last 30 years when compared to the previous 30 years, though the robustness of this result is sensitive to the time periods analyzed.