Flood in Radford (c) County, Virginia

The New River at Radford (RDFV2) flooded with a crest of 21.71 feet (93,500 cfs) near midnight on May 22nd. This was the 6th highest crest on record. Major flood stage is 20 feet and Moderate flood stage is 16 feet. Stage and discharge records are available back to 1896 for this gage. According to USGS data it was roughly a 10-year flood event (0.1 annual chance of occurrence).

An upper-level low became cut-off over the southern Appalachian region for several days leading to persistent rainfall and eventually some flooding. Four-day (96-hour) rainfall amounts ending at 800 AM EDT on May 22nd ranged from 3 to over 12 inches in the most favored locations. Some of the 11-inch+, 4-day rain totals in Roanoke County were within the 200-year recurrence interval (9.78 to 11.8 inches) per NOAA Atlas 14. The flooding that ensued was almost all in the form of river flooding that took several days to develop. Nearly every major river basin saw some flooding, but the most notable occurred in the New River basin where crests ranged from the 4th to 8th highest on record at the Virginia gaging stations along the river. Stages on the upper New were higher than in October 2018 when the remains of Hurricane Michael transited the region. The incredible rainfall, runoff and numerous debris flows produced widespread damage to roads in the region with VDOT reporting over $5 million in damages.