*Featured image above courtesy letchworthparkhistory.com*
ROCHESTER, N.Y. (WROC) — From June 14th-25th what started out as a tropical depression forming over the Yucatan Peninsula strengthened into what became Hurricane Agnes. A storm known almost 50 years later as one of the largest June hurricanes on record, and one that caused an enormous amount of widespread flooding and devastation up and along the eastern U.S. coast, and parts of Western New York.
Hurricane Agnes Track
From its birth as a tropical depression it made its way into the Caribbean Sea, strengthened into a tropical storm, and went on to become a Category 1 Hurricane over the Gulf of Mexico. It then went through the natural cycle of strengthening and weakening as it made its way from the warm ocean waters of the Gulf to the southeast U.S. From there, things got dicey as it interacted with an incoming trough from the west. It was ultimately the storm turning into an extratropical cyclone that ended up producing enormous amounts of rain over parts of our region, and resulting in a major flooding event that unfolded across the Southern Tier and parts of Western New York.
Rainfall data below courtesy of the National Climatic Data Center in Asheville, North Carolina
Well after the storm had weakened from hurricane status, some of the worst and heaviest rainfall occurred over places like Pennsylvania and the Southern Tier of New York as it became an extratropical system. The storm overall wasn’t necessarily the strongest one around, but it surely made a lasting impact on many.
The most destructive and devastating flooding to occur from this storm was in the Susquehanna River basin in Pennsylvania with the Genesee River Basin in Western New York taking on impacts of its own.
The event is known locally to many as “The Flood of ’72”, and for good reason. What didn’t help the cause was the large amount of rain and shower activity the region already saw a week prior to this storm event. On the evening of June 20th, heavy rain from Agnes began and lasted all the way through the 25th.
The maximum official rain total recorded from the event over the Genesee River Basin was 13.7” at Wellsville, NY with others reporting a total of 16″ of rain. Flooding at the Mount Morris Dam broke all historical records, river stage gauges were destroyed, hundreds of roads and bridges were washed away, and lots of debris created damming along the stream channel.
Wellsville, NY was the hardest hit in the Genesee river basin, but the lower Genesee from Mount Morris to Rochester was spared of the worst flooding due to the operations of the dam at the time. Flood levees downstream of Dansville, NY were also overtopped, and it took almost the rest of the summer to drain the fields following the flooding as well.
Next year in 2022 will mark 50 years since the event with no doubt many will be sharing their stories of how their community was impacted by the storm.
~Meteorologist Christine Gregory