Flash Flood — Mercer, West Virginia

2025-02-15 to 2025-02-16 · near Flat Top, Mercer, West Virginia

Event narrative

Heavy rain had caused multiple streams and creeks across the county to flood out of their banks and across nearby roads and properties. This included Daves Fork, Christians Fork, Lorton Lick Creek and the Bluestone River. In the Green Valley area, the South Fork Brush Creek was observed flooded out of its banks across Blue Prince Road. In Bluefield, the fire department was called out to block off multiple streets that became flooded and impassible. In the Town of Princeton, several roads were reported to be flooded and impassible, among them was Stafford Drive from Trent Street to Ingleside Road where a vehicle became stranded. Multiple swift water rescues were reported from across Mercer County due to vehicles becoming stranded in the water, as well as homes becoming surrounded by the inundation. Of those, four people were rescued from a camper that floated down Buttermilk Junction Road due to Crane Creek flooding that area. Nearby, one motorist required rescue when the vehicle became stranded in flooding near the intersection of Crane Creek Road and Lorton Lick Road. Near the community of Montcalm, a Facebook post indicated that Crane Creek had risen rapidly out of its banks and surrounded homes on Jims Branch Road. Multiple residents along the road required rescue to evacuate the homes, but it is uncertain to what extent the homes were inundated with flood waters. Widemouth Creek was observed overflowing its banks and inundating portions of Route 10 in the community of Matoaka, with floodwater reported to have entered homes and businesses in the surrounding area. At least two swift water rescues were reported taking place near the creek. Two water rescues were reported taking place along Kegley River Road. There were 479 homes affected, with 90 homes sustaining major damage and 18 were reported destroyed. Roadways and other infrastructure also experienced damage.

Wider weather episode

A deep upper level trough was observed exiting the southern Rockies during the morning of February 15th, with southwesterly windflow ahead of the trough allowing for a fetch of deep moisture from the western Gulf of America. This moisture pooled along a warm front situated across from Kentucky into southwest Virginia, where precipitable water values increased from 0.6 to 0.7 inches at 7 am that morning, to around 1.1 to 1.2 inches by early afternoon, which would be around 2 standard deviations above normal for mid-February. While the warm front shifted northward to the west of the Appalachians, high pressure off the Atlantic coast that was wedged against the eastern face of the Appalachians delayed the northward progress of the warm front. As such, the front provided the focus for training of bands of heavy rain that fell across southeast West Virginia through much of the day on February 15th. The rain fell at rates of 0.3 to 0.5 per hour beginning at around 9 am EST in the morning, which persisted for a 9-10 hour period. Rainfall totals ranged from 2 to 3.5 inches across southeast West Virginia during this period. Soils across the area were nearly saturated from 2 rounds of widespread precipitation that fell earlier in the month. Additionally, the rain was falling over ground that was partially frozen, and covered in snow and ice from a winter storm that impacted southeast West Virginia a few days earlier, increasing the rapid runoff potential into the creeks and rivers. In this event, CREST Unit Streamflow did not show impressive returns, while MRMS underestimated some of the precipitation totals. It was those factors combined with the high runoff potential of the rainfall that resulted in a lack of realization how quickly river levels were rising, and just how intense the flooding was becoming. CREST Hydrophobic Unit Flow proved to be a more accurate tool in this situation given the frozen ground, with returns as high as 500 cfs/m^2 across Mercer County, which is where some of the most intense flooding was observed. Because MRMS was underestimating rainfall amounts, both the FLASH ARI and QPE/FFG values were also significantly underestimated. In these situation, monitoring ground-truth precipitation totals from a network of private weather stations might have prompted Flash Flood Warnings to be issued sooner.

View location on OpenStreetMap → (37.5805, -81.1020)

Source: NOAA Storm Events Database, event_id 1239511. Narrative written by the NWS forecast office that issued the report.