2002 La Plata tornado

The 2002 La Plata tornado was an extremely powerful and fast moving multi-vortex F4 tornado that devastated the town of La Plata, Maryland, killing 3 people and injuring 122 others. It was the costliest tornado of the tornado outbreak of April 27–28, 2002 causing at least $115 million in damages. It is also one of the strongest tornadoes ever to hit the greater Baltimore-Washington D.C. area.

At approximately 6:56 pm (EST), the tornado touched down south of Marbury in western Charles County, Maryland. Just six minutes later, the tornado began crossing over La Plata, killing one person. At 7:30 pm, two more people died as the twister entered Calvert County. Next, it moved into the Chesapeake Bay just north of the Calvert Cliffs Nuclear Power Plant. After crossing the bay, the tornado moved across Dorchester County, again intensifying to F3 strength before dissipating west of Salisbury, Maryland. The tornado had one of the fastest-accepted forward speeds on record.

Meteorological synopsis
During that afternoon, a tornado formed from a supercell that developed in central West Virginia and moved across the Appalachian Mountains. The thunderstorm first became tornadic near Quicksburg, VA. Several tornado warnings were issued for Rockingham and Shenandoah counties, where an F2 tornado occurred. At 6:45 pm (EST), a severe thunderstorm warning was issued for northern Charles and Calvert Counties in which a call-to-action statement mentioned the possibility of tornadoes. Just 17 minutes later - at 7:02 pm, six minutes after the tornado touched down - tornado warnings were issued for both Charles and Calvert Counties.

Unfortunately, when the warnings were issued, there was a problem with the EAS activation process; 53 percent of the radio stations broadcasting in the La Plata listening area experienced outages or other issues. Around the same time, eyewitness accounts indicated that a second tornado formed one-quarter of a mile south of the primary tornado. Shortly after between 7:02 and 7:07 p.m., both tornadoes crossed through the heart of La Plata, causing catastrophic damage. As the primary tornado continued eastward through the rest of Charles County, the secondary tornado dissipated after peaking at F2 intensity.

At approximately 7:30 pm, after striking Benedict, Maryland, the tornado began its path through Calvert County, causing widespread F1/F2 damage. After leaving Calvert and crossing through the Chesapeake Bay, the tornado entered Dorchester County and intensified back to F3 strength, leaving a path of destruction before dissipating west of Salisbury, Maryland.

The La Plata tornado stayed on the ground & bay for 90 minutes, causing a 78-mile path of damage and destruction through southeast Maryland. This makes it one of the longest lasting and farthest traveling tornadoes outside tornado alley. Per NOAA's assessment of this event, only six other F4 tornadoes have occurred farther north and east of the United States. None were as close to the coast. It also had an incredibly fast average forward speed of 52 mph, making it one of the fastest violent tornadoes on record.

Impact
The tornado took a path through Charles, Calvert, Dorchester and Wicomico Counties, downing or uprooting thousands of trees and leveling several structures, including catastrophic structural damage in downtown La Plata, where approximately 65 percent of the area was heavily damaged or destroyed. 3 people were directly killed, while some 122 others were injured. In total the tornado inflicted $115 million in damage, making it the costliest Mid-Atlantic tornado.

After touching down, F1 damage was reported near Pisgah where a house was unroofed. Shortly afterwards, F3 damage was observed in two subdivisions west of La Plata. Unfortunately, as the tornado moved southeastward, it continued to strengthen while tearing through downtown La Plata, with swaths of F4 being observed. Along MD 6, cars were tossed & thrown over, with the 125-foot city water tower also being blown over. At the Posies Market, only a few walls were left standing. "Heavy F4 damage" was noted just east of the lumber yard. While moving through La Plata, the tornado was likely moving at the unusually fast speed of 58 mph, nearly a mile a minute, with destruction occurring in near seconds. After leaving downtown La Plata, a heavily wooded area sustained catastrophic levels of damage, with several anchored building being leveled or swept clean off their foundation. A 51-year-old man was killed with his wife being critically injured when their house, which was under construction, on Hawkins Gate Road collapsed. In one of the leveled homes near Normandie and MD 6, seven people were inside and all miraculously managed to survive. 3 were already in the basement, 2 others were on the first floor, with the last 2 still being on the second floor. In total across Charles County, 638 homes were damaged while 100 others were completely destroyed. 143 business (mainly in downtown La Plata) were damaged with 49 others being destroyed. At approximately 7:30 pm, the tornado moved into Calvert County south of the Patuxent River Bridge (MD 231) and struck the Patuxent View development in which over half of the homes were damaged. A home with no anchoring or foundation east of this area was picked up and thrown 80 feet into a culvert, unfortunately killing an elderly couple who were in the house at the time. The tornado damage in Calvert was rated at F1 to F2 intensity, with 125 homes being damaged. Another 10 houses were completely destroyed. After the destruction in Calvert, the twister traveled into the Chesapeake Bay just north of the Calvert Cliffs Nuclear Power Plant with damage occurring along the shoreline.

While crossing the Chesapeake Bay, a second satellite tornado tornado formed. The 2nd tornado didn't produce any damage and dissipated before making landfall. After crossing the Chesapeake Bay, the main tornado pushed into Dorchester County just south of Taylor's Island. F3 damage occurred to one house and several outbuildings near Hip Roof Road. Debris such as canceled checks, bank/tax documents, and teller receipts from La Plata were also found in southern Delaware, well over 60 miles away.

Despite the unusual circumstances, there were only five total fatalities attributed to the tornado; three as a direct result of the storm and two from indirect effects.

Preliminary F5 rating
The tornado was initially rated F5 but was downgraded in a secondary damage survey. For a small period of time, this made it the easternmost F5 tornado in the United States. This preliminary F5 rating, partly due to damage to a brick building in downtown La Plata, was lowered to F4 after the damage assessment team determined that some of the damage was due to flying debris from a lumber company nearby. Damage to houses initially rated F5 were lowered when engineer Timothy Marshall surveyed and determined these homes were not properly anchored, causing them to be swept off their foundations by lesser winds. While impressive, team members agreed that the tornado damage was not as intense as other F5 rated tornadoes such as the ones that struck Plainfield, Jarrell, Bridge Creek-Moore, or Andover. Many of the destroyed buildings or "slider homes" were only rated F1 to F3, with surveyors having to depend some ratings solely on the severity of the surrounding damage. This includes the toppled steel water tower in La Plata, which "was impressive but occurred in an area of F1 damage". This event showcased some of the prime issues with using the Fujita scale and is largely responsible for the how tornadoes are surveyed today.

Due to the extremely fast forward speed, the tornado also had less time to dwell over structures & buildings, with it moving nearly a mile a minute (96.5 km/h) in downtown La Plata. The damage likely would have been more intense with a more typical forward speed; an event again showcased during the 2021 Western Kentucky tornado. Although F4 tornadoes are already a rare event this far east, what was even more unusual was its duration and coverage for this area well outside of the climatologically favored area for violent tornadoes. Despite this, the tornado was not the deadliest one to strike La Plata. On November 9, 1926, another F4 tornado killed 13 school children and 4 townspeople, while injuring some 65 others.

Aftermath
In the wake of the tornado, Gov. Parris N. Glendening declared a state of emergency in Charles, Calvert and Dorchester counties with County schools and offices closing also. The Red Cross helped place several families in nearby hotels. Just two days later over 90% of the debris were cleared off the roads, opening traffic back up to the area. With media coverage of the deadly twister being nationwide, building damage surveys were being done by the Federal Emergency Management Agency's, Building Performance Assessment Team, and Wind Engineering Research Council during the same time the NWS was conducting their damage survey.

Due to this event, La Plata placed several tornado sirens all around and near the town for preparation on future storms. A memorial garden has since been put up in La Plata, with several benches memorialize those who died from the 1926 and 2002 tornadoes. This event is also largely responsible for the modern use of the Enhanced Fujita scale.