May 31

On May 31, 1889, the South Fork Dam collapsed after days of heavy rain, unleashing an 18-meter-high flood wave on Johnstown, Pennsylvania. The torrent obliterated homes, mills, and infrastructure, sweeping away thousands of lives in minutes. Recovery efforts by local communities and national relief organizations followed, marking one of the first major American disaster relief operations. Investigations revealed lapses in dam maintenance by the wealthy South Fork Fishing and Hunting Club. The catastrophe prompted reforms in dam engineering and liability laws across the United States. Images of the ruined town and its victims circulated globally, making the Johnstown Flood a symbol of industrial era risks. Memorials and reconstructed structures stand today to honor those lost and to remind future generations of the importance of safe infrastructure.

On May 31, 1924, a fire broke out at the Hope Development School near Colp, Illinois, a residential institution for disabled children. Flammable building materials and the absence of adequate fire escapes contributed to the rapid spread of the blaze. Locked doors and insufficient staffing hindered evacuation efforts, trapping many students inside. In total, 24 children perished, prompting public outrage over institutional safety standards. The tragedy led to reforms in fire safety regulations and greater oversight of care facilities for vulnerable populations.

In the early hours of May 31, 1935, a catastrophic 7.7 magnitude earthquake struck near Quetta, then part of British India. The tremor leveled the city, causing widespread collapse of unreinforced buildings and killing an estimated 40,000 residents. Aftershocks hampered rescue operations, and the remote location slowed the arrival of relief teams. The disaster is remembered as one of South Asia’s deadliest earthquakes, highlighting the need for seismic-resistant construction. International aid and military assistance eventually helped rebuild Quetta and improve emergency response planning.

On May 31, 1970, a massive magnitude 7.9 earthquake devastated Peru’s Ancash region, generating enormous ground shaking and triggering a colossal landslide that engulfed the town of Yungay. The quake, one of the deadliest in South American history, reached a maximum intensity of VIII (Severe) on the Mercalli scale. Within moments, a mountainside collapse from Mount Huascarán unleashed an avalanche of rock and ice, burying Yungay and nearby villages under millions of cubic meters of debris. Estimates of the death toll range from 66,000 to 70,000, with an additional 50,000 injured and many more left homeless. Rescue efforts were hampered by damaged infrastructure and the remoteness of affected areas, prolonging the agony of survivors. The disaster prompted major reforms in Peru’s emergency response systems and remains a poignant reminder of the region’s seismic risks.

Indian Airlines Flight 440, a Boeing 737, attempted to land at Delhi's Palam Airport in heavy rain and poor visibility. During the approach, the aircraft descended below the glide path and struck a hillock before reaching the runway. Of the 65 passengers and crew on board, 48 lost their lives in the impact and ensuing fire. Rescue teams faced challenging conditions due to bad weather and limited airport lighting. The subsequent investigation highlighted pilot error and prompted revisions to landing procedures in adverse weather. This accident remains one of the deadliest in Indian civil aviation history.

On May 31, 1985, a powerful storm system produced 41 confirmed tornadoes across the U.S. states of Ohio, Pennsylvania, New York, and southern Ontario in Canada. The outbreak struck rapidly, catching many communities off guard and causing widespread destruction. Homes, farms, and businesses were damaged or destroyed, with mobile and rural areas particularly hard-hit. The death toll reached 76, and hundreds were injured. This event is remembered as one of the deadliest and most extensive cross-border tornado outbreaks in North American history. The outbreak led to improvements in tornado warning systems and public awareness campaigns in both countries.

On May 31, 2013, the El Reno tornado formed in Canadian County, Oklahoma, and quickly expanded to a record-breaking width of 2.6 miles, the widest ever documented. With peak winds exceeding 300 mph, it carved a devastating path across rural and suburban areas before dissipating. The tornado claimed eight lives, including three veteran storm chasers, and injured more than 150 people. Its sudden shifts in direction and speed caught many by surprise, highlighting the unpredictable nature of violent storms. Meteorologists have since studied the event extensively to improve forecasting models and storm-chaser safety protocols. The tragedy underscored the importance of timely warnings and robust emergency planning in tornado-prone regions.