President Richard Nixon studies the flood damage in the aftermath of Hurricane Agnes, near Harrisburg, Penn. from his helicopter window, June 24, 1972. The president toured the Maryland-Pennsylvania area from his retreat at Camp David, Maryland. (Charles Tasnadi/AP)

Just as the Watergate scandal was unfolding, residents of the mid-Atlantic and Northeast would have to deal with a tropical system that had formed over the Yucatan Peninsula on June 14. That system, dubbed Agnes, would later cause some of the worst flooding ever recorded in the region’s history, particularly Pennsylvania.

Hurricane Agnes forming in the Gulf of Mexico on June 17, 1972 ( National Weather Service )

Rainfall totals from Hurricane Agnes (National Weather Service)

Flooding on the Patuxent River at Laurel, MD along Main Street. (Dennis F. Gillen, U.S. Geological Survey)

(National Weather Service)

As the Capital Weather Gang reported on August 25, 2011, “the most tragic aspect of this event in the Washington area was the loss of sixteen people who were swept to their deaths in the swirling floodwaters. Most of these drownings involved motorists that were trapped in automobiles.”

Link: Washington’s worst five hurricanes and tropical storms

(National Weather Service)

Maryland/D.C./Virginia rainfall totals

Officially, a relatively modest storm total of 8.16 inches of rain fell at Reagan National Airport (DCA) during the period ending on June 22, 1972. However, rainfall was much heavier at other nearby locations, particularly to the west, as Dulles International Airport (IAD) recorded 13.65 inches (5.74 inches in one 6-hour period). For the month, DCA recorded 11.53 inches and Dulles 18.19 inches, far above the normals of 3.78 and 3.98 inches, respectively!

Pennsylvania effects

In Pennsylvania, Hurricane “Agony,” as it was called there by then Governor Milton Shapp, dealt a devastating blow, at one point causing the Susquehanna River to rise so high that the governor was forced to evacuate his Harrisburg mansion. Forty-eight deaths—more than any other state--were ultimately reported in the Keystone State and property damage was extensive, approximating $2.1 billion, two thirds of the entire East Coast toll. This included 68,000 homes and 3,000 businesses destroyed by fire or flood. In addition, 220,000 Pennsylvanians were left homeless.

By most accounts, the scope of the above devastation places Hurricane Agnes at the top of Pennsylvania’s worst natural disasters, even though it did not cause the most deaths. The two deadliest, both of which occurred on May 31, were the Johnstown Flood of 1889 (2200+ fatalities) and the Great Pennsylvania Tornado of 1985 (65 fatalities).

As reported by USA Today on Agnes’s 30th anniversary in 2002:

Flooding forced whole towns to evacuate, including residents of Watsontown, a Susquehanna river town in Northumberland County. When people woke up on June 22 to the sirens of fire engines, many roads were already flooded and blocked off by police. Upriver in the hard-hit Wyoming Valley, rushing water tore out a section of a cemetery in Forty Fort, near Wilkes-Barre, and washed away about 2,000 caskets, leaving body parts on back porches, roofs, and basement floors.


Its printing press nearly submerged and offices flooded, Harrisburg’s morning newspaper, The Patriot, did not publish on June 23 for the first time since it opened in 1854, said Dale Davenport, the editorial page editor of what is now The Patriot-News.

Agnes’ place in history

Hurricane Agnes was the first (named) tropical storm of the 1972 hurricane season*, which should probably serve as a warning for the 2012 season: though a “near normal” hurricane season is predicted by NOAA and an average to below average one by the Weather Channel, Accuweather, Colorado State, and WeatherBell, it takes only one, of course, to wreak havoc--and we’ve already had three. (The 1981-2010 30-year hurricane season [June 1 to November 30] average is 12.1 named storms, 6.4 hurricanes, and 2.7 major hurricanes.)

Interestingly, in a story (“Washington’s Worst Floods”) posted on May 6, 2011 by WTOP 9 News Now, “the flooding that resulted from such copious rainfall [as Agnes produced] remains the benchmark for how devastating flooding can be across the Mid-Atlantic Region. The Potomac River peak stream flow measured in cubic feet per second (CFS) in the aftermath of Agnes set a record of 359,000 CFS. That’s compared to the January 1996 flooding flow of 347,000 CFS. To put that in perspective, the average stream flow for the month of January along the Potomac is only 13,000 CFS.”

Agnes basic information

Formed: June 14, 1972

Dissipated: June 23, 1972

Main areas affected: Yucatán Peninsula, western Cuba, Florida Panhandle, Georgia, North Carolina, Virginia, Maryland, Pennsylvania, New York

Total number of deaths: 128

Lowest barometric pressure: 28.85 in.

*Although there was an earlier subtropical storm named “alpha.”

Additional information links

Agnes remembered, 40 years ago at the Middle Atlantic River Forecast Center

Hurricane Agnes 40th Anniversary - 2012 fact sheet from National Weather Service Office in Sterling, Va.