Abstract
Abstract. Windstorms are a major natural hazard in many countries. The objective of this study is to identify and characterize intense windstorms during the last 4 decades in the US Northeast and determine both the sources of cyclones responsible for these events and the manner in which those cyclones differ from the cyclone climatology. The windstorm detection is based on the spatial extent of locally extreme wind speeds at 100 m height from the ERA5 reanalysis database. During the top 10 windstorms, wind speeds exceed their local 99.9th percentile over at least one-third of land-based ERA5 grid cells in this high-population-density region of the USA. Maximum sustained wind speeds at 100 m during these windstorms range from 26 to over 43 ms−1, with wind speed return periods exceeding 6.5 to 106 years (considering the top 5 % of grid cells during each storm). Property damage associated with these storms, with inflation adjusted to January 2020, ranges from USD 24 million to over USD 29 billion. Two of these windstorms are linked to decaying tropical cyclones, three are Alberta clippers, and the remaining storms are Colorado lows. Two of the 10 re-intensified off the east coast, leading to development of nor'easters. These windstorms followed frequently observed cyclone tracks but exhibit maximum intensities as measured using 700 hPa relative vorticity and mean sea level pressure that is 5–10 times the mean values for cyclones that followed similar tracks over this 40-year period. The time evolution of wind speeds and concurrent precipitation for those windstorms that occurred after the year 2000 exhibit good agreement with in situ ground-based and remote sensing observations, plus storm damage reports, indicating that the ERA5 reanalysis data have a high degree of fidelity for large, damaging windstorms such as these. A larger pool of the top 50 largest windstorms exhibit evidence of only weak serial clustering, which is in contrast to the relatively strong serial clustering of windstorms in Europe.
Highlights
1.1 Hazardous wind phenomenaHazardous wind phenomena span a range of scales from extra-tropical cyclones down to downburst and gust fronts associated with deep convection (Golden and Snow, 1991)
This analysis focuses on windstorms in the northeastern region of the United States as defined in the National Climate Assessment (USGCRP, 2018) (Table 1, Fig. 1a)
The maximum wind speed at 100 m a.g.l. in any ERA5 grid cell at the peak hour ranges from 25 to 41 ms−1, while the maximum during the storm period ranges from 26 to 44 ms−1 (Table 2). These maximum wind speeds do not scale with the storm intensity as measured by the number of grid cells that exceed their local 99.9th-percentile wind speeds (Table 2)
Summary
1.1 Hazardous wind phenomenaHazardous wind phenomena span a range of scales from extra-tropical cyclones down to downburst and gust fronts associated with deep convection (Golden and Snow, 1991). We focus on large-scale, long-duration “windstorms” associated with extra-tropical cyclones since they are likely to have the most profound societal impacts These large-scale windstorms are a feature of the climate of North America and Europe and a major contributor to weather-related social vulnerability and insurance losses (Della-Marta et al, 2009; Feser et al, 2015; Hirsch et al, 2001; Changnon, 2009; Ulbrich et al, 2001; Haylock, 2011; Lukens et al, 2018; Marchigiani et al, 2013). New York state ranks 10th of the 50 US states in total direct economic losses related to natural hazards, with estimated losses of USD 12.54 billion in 2009 USD between 1960 and 2009 (Gall et al, 2011)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
