A deep, closed upper level low pressure system was observed over central Alabama on the morning of May 28th. The east winds around this low, allowed deep sub-tropical moisture from the Atlantic to move into lower Mid-Atlantic region. Areas of rain developed across the mountains by late morning, and gradually increased in coverage due to the sustained 25 to 30 knot (850mb) moisture inflow. Precipitable water values were observed in the 1.2 to 1.3 inch range through the day into the early morning hours of the 29th, which is around the 75th percentile for late May. Through the 28th into the early morning hours of the 29th, the upper low drifted eastward, allowing instability to increase across the central Appalachians as the associated pocket of cooler upper level temperatures approached. While Surface-based CAPE levels remained minimal during the event, Most-Unstable CAPE (MUCAPE) values were observed climbing across the mountains through the evening of the 28th into morning of the 29th, reaching into the 600 to 850 J/Kg range. Combined with orographic lift, this instability supported the development of low-topped thunderstorms with enhanced rainfall rates.  As rainfall totals increased across the mountains and soils approached saturation, flash flood guidance values were lowered to under an inch at the 1- and 3-hour time periods. Training of low-topped cells passed across the Bluefield area between 6 AM and 7 AM with sustained 1.5 to locally 2 inch per hour rates. High runoff resulted in rapid street flooding, with water then quickly surrounding and entering homes. Between 500 and 1,000 homes received some form of water damage. The heavy rain then led to flooding of the Bluestone and East Rivers.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 07:00:00 to 29-MAY-23 12:00:00 (EST-5)
Location: BLUEWELL
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The Mercer County Sheriff's Department received multiple reports of flash flooding in the Bluewell Community due to 1.5 to 2.5 inches of rain falling between 5 AM and 7 AM EST, on top of 1.5 to 2.25 inches that had fallen since the evening of the 28th.  Multiple water rescues occurred as several creeks rose out of their banks and either surrounded or entered homes.  This includes a home along Lorton Lick Road that was flooded by Lorton Lick Creek, requiring the rescue of six occupants.  Another home was flooded along Ellen Avenue, requiring the rescue of another six people.  Several homes were flooded along Pinnacle Lake Road as Lick Branch rapidly overflowed its banks.  In addition, flood waters caused a portion of Warden Avenue to collapse, making the road impassible.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 16:05:00 to 30-MAY-23 14:15:00 (EST-5)
Location: SPANISHBURG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Bluestone River near Spanishburg, WV (SPNW2), rose above flood stage and crested above 16.51 feet at 3:10 am EST (0810 UTC) on the 30th, which is 1.51 feet above moderate flood stage. This is the 4th-highest documented crest in the history of this gage. Flooding from the river was observed about a foot deep across Highway 19/Beckley Road across the parking lot of the Rich Creek Baptist Church. Water rose up to the foundation of the church itself before receding.  A local resident reported water flooded Highway 7/Gardner Road near the stream gage.

Debris Flow in MERCER, WEST VIRGINIA
From 29-MAY-23 07:25:00 to 29-MAY-23 07:25:00 (EST-5)
Location: ONEY GAP
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A debris flow was observed along Mt. Horeb Road due to several hours of moderate to heavy rainfall.  The road was blocked by the debris and was reopened after the debris was cleared.  The property damage is the estimate for removing the debris.

Heavy Rain in MERCER, WEST VIRGINIA
From 27-MAY-23 23:00:00 to 29-MAY-23 23:00:00 (EST-5)
Location: (BLF)MERCER CO ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

The ASOS (Automated Surface Observing Station) at the Mercer County Regional Airport (KBLF) recorded a 48-hour rainfall total of 4.45 inches.  This includes a 3-hour total of 1.86 inches that fell between around 530 AM and 830 AM EST, which is between a 5-year (20% AEP) and a 10-year (10% AEP) Average Recurrence Interval event per NOAA Atlas 14 Point Precipitation Frequency estimates. This is the second highest two-day total of rainfall for this station since September 1959.

Heavy Rain in MERCER, WEST VIRGINIA
From 28-MAY-23 06:00:00 to 30-MAY-23 06:00:00 (EST-5)
Location: BLUEFIELD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The Cooperative Weather Observer at Bluefield, WV (BLFW2) observed a 2-day rainfall total of 4.58 inches.  Dating back to December 1998, this is the highest 2-day total in the history of this Cooperative Observer station.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 10:30:00 to 29-MAY-23 14:30:00 (EST-5)
Location: ADA
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The East River flooded out of its banks across Country Girl Road.  At some point, two vehicles became stranded in the flood waters, and the vehicles required towing after the flooding receded.  It is unclear in the occupants of the vehicles required any form of rescue from emergency personnel.  The property damage is the estimated damage to both of the vehicles.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 08:00:00 to 29-MAY-23 12:00:00 (EST-5)
Location: BRUSH FORK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A social media photo showed the Midway Tunnel at least eight feet deep as an unknown-named tributary running parallel to the railroad tracks above the tunnel overflowed its banks.  No damage was reported, and the tunnel was allowed to reopen after the flooding receded.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 08:45:00 to 29-MAY-23 08:45:00 (EST-5)
Location: CERES
Flood cause: Heavy Rain
Property damage: 15.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Runoff from heavy rain caused a portion of Ada Number 29 Road to collapse, making the road impassible.

Heavy Rain in MERCER, WEST VIRGINIA
From 28-MAY-23 11:00:00 to 29-MAY-23 11:00:00 (EST-5)
Location: CUMBERLAND HGTS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A personal weather station (Weather Underground: KWVBLUEF23) recorded a 24-rainfall amount of 5.25 inches. This is about a 200-year Average Recurrence Interval event per NOAA Atlas 14 Point Precipitation Frequency estimates. Runoff from this location flows into the East River.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 11:10:00 to 29-MAY-23 13:40:00 (EST-5)
Location: WILLOWTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The East River at Willowton, WV (ERVW2), crested at 9.68 feet (3,380 cfs) at 1:00 pm EST (1800 UTC) on the 29th above the flood stage of 9.0 feet.  This is the 9th-highest documented crest of this gage since 2012, and is between a 2-year and a 5-year event (50%-20% Annual Exceedence Probability) per USGS StreamStats.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 08:00:00 to 29-MAY-23 11:00:00 (EST-5)
Location: MONTCALM
Flood cause: Heavy Rain
Property damage: 8.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Lorton Lick Creek rose out of its banks due to heavy rainfall and flooded across multiple roads, including portions of Lorton Lick Road.  One vehicle was stranded in the flood waters and required towing after the flooding receded.  The property damage is the estimated cost of damage to the vehicle.

Heavy Rain in MERCER, WEST VIRGINIA
From 28-MAY-23 11:00:00 to 29-MAY-23 11:00:00 (EST-5)
Location: GLENWOOD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A personal weather station (Weather Underground: KWVPRINC14) recorded a 24-rainfall amount of 3.48 inches. This is about a 10-year (10% AEP) Average Recurrence Interval event per NOAA Atlas 14 Point Precipitation Frequency estimates. This includes about one inch that fell between 7am and 8am on the 29th, with rainfall rates of up to 1.5 inches per hour during this time.  Runoff from this location flows into Brush Creek.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 08:00:00 to 29-MAY-23 12:00:00 (EST-5)
Location: BLUEFIELD
Flood cause: Heavy Rain
Property damage: 12.00K
Crop damage: 0.00K
Reported by: Broadcast Media

The WVVA-TV webpage showed standing water around two feet deep within a low spot on Bland Street.  A car was stranded in the flood water, and it appears that the flood water was high enough to enter at least one business there.  Property damage includes estimates for damage to the flooded vehicle and for the business.

Debris Flow in MERCER, WEST VIRGINIA
From 29-MAY-23 16:46:00 to 29-MAY-23 16:46:00 (EST-5)
Location: ADA
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A debris flow occurred along Chicory Road, making the road impassible until the debris was cleared.  Property damage is the estimated cost of the cleanup detail.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 08:45:00 to 29-MAY-23 09:00:00 (EST-5)
Location: NEW HOPE
Flood cause: Heavy Rain
Property damage: 16.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The North Fork of Brush Creek flooded out of its banks and was flowing across Ceres Road over a foot deep.  Two automobiles became stranded while attempting to pass through the flood waters and were required to be towed after flooding receded.

Heavy Rain in MERCER, WEST VIRGINIA
From 28-MAY-23 11:00:00 to 29-MAY-23 12:00:00 (EST-5)
Location: CUMBERLAND HGTS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A personal weather station (Weather Underground: KWVBLUEF26) recorded a 24-rainfall amount of 4.48 inches. This is about a 50-year Average Recurrence Interval event per NOAA Atlas 14 Point Precipitation Frequency estimates. Runoff from this location flows into the East River.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 07:00:00 to 29-MAY-23 10:00:00 (EST-5)
Location: BRUSH FORK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Stoney Ridge Road was flooded over one foot deep by flowing water due to an unknown-named creek having risen out of its banks.  No damage to the road was reported and it was reopened after the flooding receded.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 06:30:00 to 29-MAY-23 12:00:00 (EST-5)
Location: (BLF)MERCER CO ARPT
Flood cause: Heavy Rain
Property damage: 200.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The Mercer County Sheriff's Office received numerous reports of flash flooding across the City of Bluefield WV due to 1.5 to 2.5 inches of rain falling between 5 AM and 7 AM EDT, on top of 1.5 to 2.25 inches that had fallen since the evening of the 28th.  The most concentrated number of reports occurred near the intersection of Bland Street and College Avenue, where 2 inches of rainfall occurred in one hour.  Both Bland Street and College Avenue were flooded by over a foot of rushing water in places.  At least one vehicle was stranded in the flood waters, with three occupants requiring help by a swift water rescue team.  Several basements in the area were also flooded by several feet of water, including in homes on Bland Street, Union Street, Jefferson Street and College Avenue.  Portions of Lynn Street and Walters Avenue were flooded and impassible until the water receded.  One swift water rescue was required for the occupant of a vehicle that became stranded by flooding along Grassy Branch Road as Grassy Branch rose out of its banks over a foot deep across the road.  Another swift water rescue occurred when a vehicle traveling on Airport Road became stranded in flood waters when a tributary of Brush Creek rose out of its banks over a foot deep.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 16:00:00 to 30-MAY-23 14:05:00 (EST-5)
Location: KEGLEY
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Social Media

Social media photos showed Highway 19/Beckley Road flooded at least a foot deep by the Bluestone River overflowing its banks.  Portions of Soaring Eagle Lane were also flooded.  Multiple modular homes along Soaring Eagle Lane were surrounded by water by the time the river crested.  Property damage estimates are from the cleanup effort as it is unknown if water actually entered any of the homes or vehicles parked at the homes.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 09:15:00 to 29-MAY-23 22:15:00 (EST-5)
Location: MONTCALM
Flood cause: Heavy Rain
Property damage: 8.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Back-water flooding of the Bluestone River up Lorton Lick Creek resulted in flooding of Lorton Lick Road.  An automobile trying to drive along the flooded road became stranded in the flood water.  The occupants had to abandon the vehicle.  Property damage is the estimate to repair the vehicle.

Flash Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 09:00:00 to 29-MAY-23 12:30:00 (EST-5)
Location: INGLESIDE
Flood cause: Heavy Rain
Property damage: 40.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The East River rapidly flooded out of its banks, and began to enter homes along Ingleside Road.  A swift water rescue team was required to evacuate the residents of one of these homes by boat.  No injuries were reported.  Property damage is the estimated cost of damage to the home caused by the flooding.

Heavy Rain in MERCER, WEST VIRGINIA
From 28-MAY-23 11:00:00 to 29-MAY-23 11:00:00 (EST-5)
Location: NEW HOPE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A personal weather station (Weather Underground: KWVEDISO2) recorded a 24-rainfall amount of 4.18 inches. This is between a 25-year (4% AEP) and a 50-year (2% AEP) Average Recurrence Interval event per NOAA Atlas 14 Point Precipitation Frequency estimates. This includes about 1.6 inches that fell between 7am and 9am on the 29th, with rainfall rates of up to 2 inches per hour during this time.  Runoff from this location flows into Brush Creek.

Flood in MERCER, WEST VIRGINIA
From 29-MAY-23 09:15:00 to 29-MAY-23 22:15:00 (EST-5)
Location: ROCK
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Highway 71, from near the Rock Post Office to near Rock River Road, was flooded and impassible due to the Bluestone River rising out of its banks across the road.  No damage aside from cleanup of the debris was observed, and the road was reopened after the flooding receded.