A new report shows significant flaws in Buffalo’s response to the massive snowstorm that struck just before last Christmas, killing 31 people in the city.

It finds that Buffalo’s snow removal fleet was no match for the storm’s hurricane-force winds and whiteout conditions. The city remained in a blizzard for more than 36 hours. According to the document, it was the longest-lasting winter storm to ever strike an area of the continental U.S. that lies below 5,000 feet in elevation.

The report shows that the city fell short in warning residents and providing shelter. Neighborhoods of color were also hit disproportionately hard. Black residents comprise about a third of Buffalo’s population. However, 20 of the 31 people who died were African-American, and two of the three electrical power substations that failed were located in the city’s predominantly-Black East Side.

There have been plenty of questions about how that storm could so thoroughly devastate an area already accustomed to heavy snow. Buffalo Mayor Byron Brown paid researchers at New York University to compile the 175-page report in an attempt to address those questions.