A significant hydrologic event took place May 4-5 as an upper level low tracked across the Tennessee Valley and pushed a complex frontal system through the region overnight.  Deep layer moisture transport from the Gulf of Mexico and low level southeast flow led to atmospheric saturation. In addition, strong jet dynamics and diffluence aloft, along with upslope flow, led to heavy rain along and east of the Blue Ridge Mountains. 24-hour rainfall totals ranged from 3-5 inches along the Blue Ridge and foothills. The top five rain gauge reports (in inches) for 24 hours ending 800 AM EDT on May 5th included Adney Gap IFLOWS (ADNV2) 5.17, Glasgow IFLOWS (GLSV2) 4.50, Sugarloaf Mtn. IFLOWS (SUGV2) 4.47, Trappers Lodge IFLOWS (TRAV2) 4.22 and Copper Hill COOP (COPV2) 3.41.

Flood in HALIFAX, VIRGINIA
From 06-MAY-17 03:30:00 to 07-MAY-17 06:00:00 (EST-5)
Location: SINAI
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Dan River at South Boston (SBNV2) flooded, reaching 21.60 feet late on May 6th (Minor Flood Stage - 19 feet).

Heavy Rain in FLOYD, VIRGINIA
From 04-MAY-17 08:00:00 to 05-MAY-17 08:00:00 (EST-5)
Location: COPPER HILL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The 24-hour rainfall of 3.41 inches at Copper Hill COOP (COPV2) ending at 0800 EST on the 5th was the 2nd highest daily rainfall in the month of May (data back to 1940), falling just shy of the record 3.54 inches on May 28, 1973.

Heavy Rain in MARTINSVILLE (C), VIRGINIA
From 04-MAY-17 08:00:00 to 05-MAY-17 08:00:00 (EST-5)
Location: MARTINSVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Martinsville FP COOP (MARV2) station had its 4th highest daily May rainfall on record with 2.53 inches in the 24 hours ending at 0800 EST on May 5th. Records at this site date back to 1930.

Heavy Rain in ROCKBRIDGE, VIRGINIA
From 04-MAY-17 08:00:00 to 05-MAY-17 08:00:00 (EST-5)
Location: GLASGOW
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The 24-hour rainfall of 3.60 inches at Glasgow 1 SE COOP (GLAV2) ending at 0800 EST on the 5th was the 2nd highest daily rainfall in the month of May (data back to 1967), falling just short of the record 4.12 inches on May 28, 1973.

Heavy Rain in CRAIG, VIRGINIA
From 04-MAY-17 08:00:00 to 05-MAY-17 08:00:00 (EST-5)
Location: NEW CASTLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP site at New Castle (NECV2) had 2.73 inches in 24 hours ending at 0800 EST, which is the 4th highest daily total for any May day. Records date back to 1907.

Flood in PATRICK, VIRGINIA
From 05-MAY-17 02:30:00 to 05-MAY-17 03:30:00 (EST-5)
Location: WOOLWINE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Smith River near Woolwine (SMVV2) in northern Patrick County crested at 9.63 feet (Minor FS ��� 9 ft.) early on the 5th. This was between a 5 and 10-year flood event (0.2-0.1 Annual Exceedance Probability, AEP) per USGS flood frequency data. A portion of Jacks Creek Road was flooded.

Flood in ROCKBRIDGE, VIRGINIA
From 05-MAY-17 04:00:00 to 05-MAY-17 08:00:00 (EST-5)
Location: COLLIERSTOWN
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

An IFLOWS stream gage on Buffalo Creek near Murat recorded a stage of 11.40 feet (Minor FS - 7 ft). Emergency management officials reported serious flooding along portions of Buffalo Creek, described as the 'worst in 22 years'. Several homes in the Collierstown area were threatened by flooding from Buffalo Creek and a water rescue was performed from a home on Palfrey Lane that was surrounded by waters from Buffalo Creek.

Flood in ROCKBRIDGE, VIRGINIA
From 05-MAY-17 04:00:00 to 05-MAY-17 08:00:00 (EST-5)
Location: KERRS CREEK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The USGS gage on Kerrs Creek near Lexington (KCKV2) shot upward to a crest of 11.16 feet (Moderate FS ��� 11 ft.) which was the highest observed stage at this gage since June 2004. The recurrence interval for the peak discharge of 7510 cfs was very close to 25-year event (0.04 Annual Exceeedance Probability or AEP) per USGS studies. Several home evacuations were required by local rescue squads in Rockbridge County. In addition at least four roads were closed in the county by flooding.

Flood in HALIFAX, VIRGINIA
From 06-MAY-17 04:00:00 to 07-MAY-17 22:30:00 (EST-5)
Location: RANDOLPH
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Flooding developed along the Roanoke (Staunton) River with the river gage at Randolph (RNDV2) cresting just over 22.68 feet (Minor FS - 21 feet) late on the 6th. Several roads near the river were closed by flood waters.