A Climatology of Significantly Severe Hail in the Northeast United States from 2011-2022

open_access
Open Access
Author:
Norman, Nicholas
Graduate Program:
Meteorology and Atmospheric Science
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
January 30, 2026
Committee Members:
Paul Markowski, Program Head/Chair
Matthew Robert Kumjian, Thesis Advisor/Co-Advisor
Kelly Lombardo, Committee Member
Keywords:
hail
forcasting
forecasting techniques
mesoscale forecasting
operational forecasting
reanalysis data
ERA5
hodograph
skew-t
hail reports
statistical analysis
severe weather
climatology
doppler radar
dual-polarization
forensic meteorology
storm mode
tornado
large hail environments
SHIP
Northeast
Northeast US
Abstract:
An analysis of NOAA Storm Events Database hail reports from 2011 to 2022 was conducted for the northeastern United States to identify cases of significantly severe (≥2 in or 51 mm in maximum dimension) hail. For each of the 167 cases observed, we also examined NEXRAD level-II data to identify convective storm mode (e.g., right-moving supercell, QLCS, etc.) and behaviors including storm splitting or mergers. Using these datasets, we performed a climatology for these events, compiling an array of statistics which included maximum reported hail size, report quantity, duration of severe (1.00 to 1.99 in or 25-50 mm) and significantly severe hail, hail report time of day and year, extent of the hail reports swath, storm motion before and during significant hail production, and tornadoes produced (if any). ERA5 reanalysis data was obtained for each case to analyze thermodynamic and kinematic environments, including computing common severe weather indices like the Significant Hail Parameter (SHIP). These data were used to create composite soundings and hodographs for each convective storm mode and other categories of statistical interest. With an average severe hail duration of roughly one hour, many of these cases were not short-lived or isolated. A few of the higher-impact events generated millions of dollars in damage over swaths greater than 100 miles (160 km) in length. The results both align with previous studies analyzing significant hail environments but also highlight a few differences unique to the northeast. This will not only aid forecasters in predicting future events in this region but also inform commercial businesses and insurance companies, such that mitigation strategies can be developed to limit property losses from these uncommon, yet prolific hailstorms.