The 1985 Election Day floods – also known in West Virginia as the Killer Floods of 1985 – produced the costliest floods in both West Virginia and Virginia in November 1985. The event occurred after Hurricane Juan, a tropical cyclone in the 1985 Atlantic hurricane season, meandered near the coast of Louisiana before striking just west of Pensacola, Florida late on October 31. Juan moved northward into Canada, but spawned another system that spread moderate rainfall across the Mid-Atlantic States, wetting soils. On November 3, a low pressure area developed south of Florida and moved northeastward along a cold front, bringing a plume of moisture influenced by Juan's previous track. The storm moved through the southeastern United States, stalling on November 5 west of Washington, D.C. before turning out to sea the next day. The event became known as the Election Day floods due to its concurrence with elections in Virginia.
Damage was heaviest in Virginia and West Virginia. In the former state, the rainfall peaked at just northeast of Montebello. The rains increased levels along many rivers to record heights across Virginia, including the James River which crested at at a station called Holcomb Rock, the highest level in the state. In Roanoke, the Roanoke River rose in ten hours to a peak of , considered a 1 in 200 year event. In the city, many residents had to be rescued after they were trapped, and three people drowned by driving into flooded waters. Considered the worst flood on record in the city, Roanoke sustained $225 million in damage, with 3,100 damaged homes and businesses. There was also flooding in Richmond after the James River crested at the second-highest level on record. Throughout Virginia, damage was estimated at $753 million, making it the state's costliest flood at the time, and there were 22 deaths.
In West Virginia, 27 river gauging stations recorded 1 in 100 year events, mostly within the Potomac and Monongahela basins. As most of West Virginia's liveable land is along flood plains, the river flooding caused heavy damage, mostly in the eastern portion. High waters washed away topsoil and thousands of trees, and over 13,000 homes and businesses in the state were damaged or destroyed. Damage was estimated at nearly $700 million, making it West Virginia's costliest flood, and there were 38 deaths. Flooding also affected Maryland, although to a lesser degree than neighboring Virginia, with $21 million in damage and one death. There was also tidal flooding in the state along the Chesapeake Bay from the storm, which washed away beaches just weeks after Hurricane Gloria affected the coastline. In Pennsylvania, flooding was worst along the Monongahela River in the state's southwest portion. During the storm, a power company opened the flood gates of the Lake Lynn dam along the river to preserve its integrity, triggering a class action lawsuit that ultimately failed. The floods damaged or destroyed 3,349 houses in Pennsylvania, causing $83 million in damage, as well as one death.
Overall damage was estimated at $1.4 billion, which would have been the fourth costliest United States hurricane if it were a tropical cyclone, and there were 62 overall deaths. The flooding spurred changes to warning practices by the National Weather Service and the Government of Virginia. In December 2011, the United States Army Corps of Engineers completed a flood mitigation project in Roanoke, Virginia that began following the 1985 floods.
Meteorological history Early on October 26, a tropical depression formed in the central Gulf of Mexico, and intensified into Hurricane Juan while meandering northward. The storm had a large wind field and was somewhat subtropical in nature. Due to weak steering currents, Juan looped once offshore Louisiana and later looped again over the state, weakening into a tropical storm over land on October 29. The storm turned eastward and later northeastward, striking just west of Pensacola, Florida late on October 31. Juan turned to the north over land and became extratropical on November 1 over Tennessee. After the remnants of Juan continued to the north into Canada, it spawned an occluded low in the Tennessee Valley. This low continued to the east through North Carolina, bringing moderate rainfall throughout the region, and saturating soils; overcast skies and the weak sunlight of early November prevented much of the rains from evaporating.
On November 3, while the low was located over North Carolina, a stationary cold front extended from the Gulf of Mexico through Michigan, which absorbed the remnants of Juan. That day, a low pressure area developed in the Gulf of Mexico south of the Florida panhandle and tracked to the northeast along the front, bringing a plume of warm tropical air into the east-central United States; the previously erratic motion of Hurricane Juan allowed this flow of moisture to extend into the mid-Atlantic. As a result, dew points reached over in North Carolina, which is unusually high for the time of year. As the storm moved through the Carolinas, it produced an area of convection, or thunderstorms, that extended to the north and west. The low stalled over Virginia on November 5 to the west of Washington, D.C., before turning to the east and exiting into the Atlantic Ocean, with rainfall ending on November 6.
Preparations and warnings Ahead of the main rainfall event, the National Weather Service (NWS) forecast office in Washington, D.C. issued a flood watch for southwestern Virginia, but canceled it early on November 4 after the heaviest rainfall was expected to continue to the northeast. Also that day, the NWS issued flood watches and warnings for portions of West Virginia. Later, special weather statements were issued in Virginia due to the continued rainfall. The Roanoke, Virginia NWS office lost telephone service shortly before the arrival of the flooding, which created difficulties in distributing warning information. Based on the rapid level increase of the Roanoke River, the Raleigh, North Carolina NWS issued a flash flood warning for Roanoke and its surrounding vicinity. The NWS also issued a river flood warning, initially anticipating a crest of , and later increasing the estimate to . In Virginia and Maryland along the western coast of the Chesapeake Bay, several low-lying and small coastal communities were evacuated. About 18,000 people were forced to evacuate in western Virginia due to river flooding. In West Virginia, residents relied on fire and civil defense sirens to receive warning about the floods, although some people in flood areas failed to receive any warning. Before the arrival of the floods, 23 of the 55 counties lacked updated disaster plans due to insufficient staff or funding, and as a result 29 counties' plans were rated "poor" or "very poor" by Federal Emergency Management Agency (FEMA).
Impact
The system dropped rainfall from North Carolina to Pennsylvania, westward to Ohio, with a peak of just northeast of Montebello, Virginia. Widespread areas reported over of precipitation, with an unofficial total of about in West Virginia. For West Virginia, November 1985 is the wettest month since records began in 1895 with a statewide mean precipitation of . Over Virginia it is the seventh-wettest month since records started with a mean precipitation of , while in Pennsylvania November 1985 is also the seventh-wettest month since 1895, with the state averaging .
Flash flooding occurred in mountainous portions of Virginia, West Virginia, and Pennsylvania, after orographic lift caused particularly high rainfall totals in the southern Appalachian Mountains. A total of 63 gauging stations along rivers and streams recorded flood magnitudes greater than the 100-year event, of which 40 surpassed the previous record by more than 50%. In addition to the floods, the storm produced the highest tidal flooding in the Chesapeake Bay and its tributaries since the 1933 Chesapeake–Potomac hurricane, and in some cases surpassed that of Hurricane Hazel in 1954. This was due to persistent southeasterly winds just days after a full moon, causing tides that reached above normal in many places in Maryland, with waves on top. Overall damage totaled $1.4 billion, and the system killed 62 people; if the system were a tropical cyclone, it would have ranked as the fourth costliest United States hurricane at the time.
While moving through the southeastern United States, the storm produced gale-force winds along the Outer Banks, and there were reports of two weak tornadoes that damaged boats. Rainfall reached in eastern North Carolina, which flooded coastal cities in combination with high tides. Crop damage in the state was estimated at $1.5 million, mostly to the soybean and wheat harvests. Flooding reached a depth of in some places, which damaged roads and affected a trailer park in Hertford County. The floods also destroyed a fish building in Colerain. In the Piedmont interior, the rainfall flooded streams, flooding some roads and houses, while in mountainous portions, upwards of of snow fell.
The high rainfall caused levels to increase along the Ohio River in Kentucky. Rainfall spread as far north as New York, which flooded basements in Amherst and increased levels along streams.
Virginia The high rainfall caused many rivers to rise above their banks across Virginia, becoming among the top three highest crests on record along several rivers in the state. The flood set the highest river stage on record along the Roanoke River at Roanoke, Tinker Creek near Daleville, the Calfpasture River at Goshen, the Craig Creek at Parr, and the James River at Buchanan, Holcomb Rock, and Bent Creek. At Holcomb Rock, the James River crested at , the highest in the state, and was about above flood stage; based on the observations and the associated discharge, the return period was estimated as greater than a 1 in 500 year event. River gauges recorded record discharge rates at 34 stations, of which 32 were 100 year events. The rains delayed crops from being planted across the state and caused minor crop damage. Across the state, about 3,500 houses were destroyed. Overall, the storm system caused 22 deaths and $753 million, greater than the devastating hurricanes Camille and Agnes, and making it the costliest flood in the state's history.
The city of Roanoke recorded in a 24‑hour period, the highest 24‑hour total on record for the city since records began in 1912; of the total, fell in about three hours. After previously wet conditions, the Roanoke River at Roanoke rapidly rose in ten hours to its peak of , well above the flood stage of . The floods were considered a 1 in 200 year event, and in one instance near Salem, the waters rose to the height of a three-story building. Many surrounding rivers, including the James River, also rose, with 63 peak discharge rates in local streams. The high rivers flooded much of downtown Roanoke, including roads, rail lines, houses, and businesses, with some roads and bridges closed for weeks. Residents survived by holding onto trees, while others, some trapped in their cars, required rescue; one helicopter rescued 125 stranded people. There were 10 deaths in and around Roanoke, including three who drove into flooded rivers, and three others who refused to evacuate. The floods damaged about 3,000 homes and 100 businesses. Overall monetary damage in the city was estimated at $225 million, with $520 million in the entire metropolitan area, making it the city's worst flood on record.