S. 25 per hour) as the upper low drifted very slowly eastward from the lower Mississippi Valley toward the southeastern states.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS RNK wrote it up.
Several waves of low pressure moved across the area as an upper level low closed off over the southeastern U.S. Signiifcant rainfall began early on April 22nd over far southwest Virginia and the rainfall persisted on and off over the next four days with mainly moderate rates (0.10 to 0.25 per hour) as the upper low drifted very slowly eastward from the lower Mississippi Valley toward the southeastern states. 24-hour totals ending 12z (0700 EST) on the 23rd ranged from less than 0.50 inches over the James River basin up to 1.25 to 1.75 across parts of the Roanoke, New and Dan basins. The heaviest rains April 23-24 fell across the western and central river basins with amounts ranging from 2 to 5 inches. Another 1 to 3 inches with isolated higher amounts fell mainly across the foothills and piedmont in the next 24-hours. Storm total rainfall for the four-day period ending at 12z (0700 EST) on the 25th ranged from 3 to 9+ inches with highest amounts in parts of the Blue Ridge mountains and foothills in Patrick, Carroll and Henry counties. Busted Rock #2 IFLOWS (BUEV2) led the way with 9.53 over the 4-day period. Widespread small stream flooding resulted with numerous larger rivers that approached or exceeded flood stage including portions of the Clinch, New, Roanoke and Dan rivers. Return frequency intervals for the flooding were generally in the 5-year to 10-year range (0.20-0.10 annual exceedance probability), but close to 20-year (0.05 AEP) in the lower Dan River. Numerous roads were closed by flooding in at least a dozen counties.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Blacksburg, VA wrote its last area forecast discussion before the first event at Apr 22, 6:47 AM EST, 13 minutes earlier.
Area Forecast Discussion National Weather Service Blacksburg VA 747 AM EDT Sat Apr 22 2017 .SYNOPSIS... A frontal boundary will stall out across our area through Saturday with several waves of low pressure moving along it. Will see a wet pattern with periods of moderate to heavier showers through Monday morning. The front moves southeast by Sunday night into Monday, with high pressure building in Tuesday. && .NEAR TERM /THROUGH TONIGHT/... As of 320 AM EDT Saturday... Forecast still looking wet, but timing of front moving southward into NC has slowed and will have to wait for deep convection and any sfc wave to move east of the piedmont this afternoon to sink the front further south. With this in mind, have upped temperatures a little in the southern 2/3rds of the CWA, despite the fact that we will be mostly cloudy to overcast with occasional showers. With increase in temps, thunderstorm chance start to increase further north. CAMs showing some decent deep convection forming along/near the Blue Ridge by early afternoon thine shifting east to the piedmont by 21z. The Storm Prediction Center has bumped the marginal risk northward to give most of the CWA an isolated svr threat. Severe parameters point toward potential supercell/multicell structures given the frontal boundary and shear in place, though thermodynamics and shear are not that great, cannot rule out isolated wind damage threat, especially southeast toward Danville/Yanceyville. The bigger concern will be heavy rainfall. Fortunately most of the rain yesterday and this morning has not been constant. Heavier amounts did fall over the Mountain Empire into the NC mountains, and this will need to be watched later today. At the moment think enough of a break between this mornings activity which is light, and convection this afternoon to allow the rain to soak into the ground and cause any streams to recede. As convection forms, a flash flood watch may be needed if storms train any, though storm motion looks to be accelerated enough to prevent long duration heavy rainfall. Look for a southward shift in showers this evening, then as next upper trough moves east into West TN while sfc low shifts to east TN a gradual shift northward may take place though all of the CWA should see rain in this time frame. Any thunderstorms will be fading after early evening in the south. With wedge front sinking southward this evening, an uptick in northeast winds will occur, especially in the piedmont/foothills of VA. Lows tonight will be cooler in the mid 40s to lower 50s. Rainfall amounts today/tonight will average around 1 inch, with locally higher amounts likely to 1.5 to 2 inches possible. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... As of 330 AM EDT Saturday... Guidance is in fairly good agreement continuing to advertise widespread significant rainfall through the weekend. A strong wedge of high pressure will remain in place as a slow moving upper closed low digs through the southeast US and drives low pressure through SC and GA Sunday into Monday. This will generate abundant isentropic lift as persistent low level southeasterly flow provides deep moisture transport over the top of the wedge. Multi-day QPF totals will be near 4 inches east of the Blue Ridge, with 2 to 3 inch amounts to the west. If this amount of rainfall occurs it will be sufficient to push area waterways out of their banks, but will hold off on any watches at this time until more exact timing and placement of heavy precipitation presents itself. The slow movement of the low as it spins off the coast will allow for only very slow improvement as precipitation gradually tapers off west to east Monday and Tuesday. Temperatures in the wedge will be a solid 10 to 20 degrees below normal on Sunday. Combined with a stiff northeast breeze and lots of rainfall, it will be feeling most unpleasant. Temperatures will slowly moderate through the first part of next week with readings approaching normal by Tuesday. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... As of 312 AM EDT Saturday... A long wave upper trough will develop over the western and central United States Wednesday and Thursday. This will steer the remnants of our weekend storm system up the East Coast. Wide spread in the long range guidance solutions after Thursday but overall looks like 500MB pattern is amplifying with troughing in the west and ridging in the east. Models have a cold front stalling through the central United States Wednesday through Friday, with the GFS on the east side of the differing solutions. Given the building southeast ridge at the end of next week WPC preference was closer the the 00Z ECMWF This keeps the Mid Atlantic region dry Wednesday through Friday with above normal temperatures. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... As of 740 AM EDT Saturday... Forecast not changed too much thinking mainly VFR to MVFR outside of showers and storms but overall look for increasing coverage of convection after midday with mainly MVFR to occasional IFR with thunder in vicinity, especially southeast of a line from BLF-FVX. Some strong storms possible toward DAN this afternoon. Tonight, keeping showers around with less thunder along with vsbys in the MVFR to IFR range as well as cigs. Winds shift from the southeast to southwest to northeast as front sags south behind first area of convection late this afternoon. Beyond midnight expect off and on rain heavy at times, with generally sub-VFR conditions. Extended Aviation Discussion... No change in the pattern and looking wet with predominant sub- VFR into Monday, with finally some improvements from west to east Tuesday. Drier and warmer mid to late next week so mainly VFR after early week. && .HYDROLOGY... As of 330 AM EDT SATURDAY... After 4 to 5 days straight days this week with spotty mainly light rainfall across the area, we are still looking at the possibility of a more significant hydro event this weekend. Despite the semi-wet week, antecedent conditions are fairly dry across the eastern 2/3 of the CWA and generally about normal in the west. Moderate drought is still depicted on the U.S. Drought Monitor across much of the piedmont and Abnormally Dry over most of the Blue Ridge and surrounding area with near normal conditions in the west. This suggests that we can absorb more water than might be typical. 3-hour flash flood guidance from the River Forecast Centers ranges generally from about 1.5 inches in the west up to around 3 to 3.5 inches in the west, reflecting well the drier conditions east of the mountains. A slight risk for convective rainfall exceeding flash flood guidance was issued by WPC earlier for Day 2 and Day 3 (through 12z Monday). Pockets of minor advisory-type flooding cannot be ruled out in convective storms which will be more likely today and Saturday and further south in the CWA where instability may be much higher. Any training convection over the same basins could produce pockets of flash flooding. At this point the river forecast is purely QPF based. Model QPFs have shown some decent run-to-run consistency over the last few cycles providing more confidence that this will fulfill expectations. Current WPC QPF in the day 1-3 period (today through early Monday) period is generally about 2 to 4 inches, with the bulk of it falling Saturday and Sunday and current WFO grids are close to these numbers. The prolonged nature of the rainfall (48 to 72 hours) will lessen the risk of serious river flooding (and flash flooding) as runoff will be more spread out and less efficient. The two best St. Louis University CIPS analogs to this event are April 9-12, 2003 and March 28-30, 2010 both of which featured upper lows over the southeastern U.S. Both events resulted in minor to moderate river flooding on the Dan River but not on the New, James, upper Tennessee or upper Roanoke Rivers. Ensemble river forecasts from the GEFS ensemble are also highlighting the Dan and portions of the Roanoke basins as the most likely to flood, suggesting a greater likelihood for moderate or higher flooding but the NAEFS has been consistently showing lower probabilities. The situation will be monitored closely on future shifts for a possible Flood Watch. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && SYNOPSIS...WP NEAR TERM...WP SHORT TERM...MBS LONG TERM...AMS/MBS AVIATION...DS/KK/WP HYDROLOGY...MBS/PC
Hazardous Weather Outlook National Weather Service Blacksburg VA 416 AM EDT Sat Apr 22 2017 NCZ001-002-018-VAZ007-009>018-022-023-WVZ042>044-230830- Ashe-Alleghany NC-Watauga-Tazewell-Smyth-Bland-Giles-Wythe-Pulaski- Montgomery-Grayson-Carroll-Floyd-Craig-Roanoke-Botetourt-Mercer- Summers-Monroe- 416 AM EDT Sat Apr 22 2017 This Hazardous Weather Outlook is for northwest North Carolina, southwest Virginia, west central Virginia and southeast West Virginia. .DAY ONE...Today and tonight. Heavy rain showers and thunderstorms will occur this afternoon and evening. Localized flooding is possible. In addition a few storms could bring isolated wind damage. .DAYS TWO THROUGH SEVEN...Sunday through Friday. A prolonged period of moderate to heavy rain is possible Sunday through Monday. This may lead to minor flooding on streams and rivers. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. NCZ003>006-019-020-VAZ032>034-043>045-058-059-230830- Surry-Stokes-Rockingham-Caswell-Wilkes-Yadkin-Patrick-Franklin- Bedford-Henry-Pittsylvania-Campbell-Halifax-Charlotte- 416 AM EDT Sat Apr 22 2017 This Hazardous Weather Outlook is for north central North Carolina, northwest North Carolina, central Virginia, south central Virginia, southwest Virginia and west central Virginia. .DAY ONE...Today and tonight. Thunderstorms this afternoon may become severe with isolated damaging winds and hail possible. Localized flooding will also be possible. .DAYS TWO THROUGH SEVEN...Sunday through Friday. A prolonged period of moderate to heavy rain is possible Sunday through Monday. This may lead to minor flooding on streams and rivers. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. VAZ019-020-024-035-046-047-WVZ507-508-230830- Alleghany VA-Bath-Rockbridge-Amherst-Appomattox-Buckingham- Eastern Greenbrier-Western Greenbrier- 416 AM EDT Sat Apr 22 2017 This Hazardous Weather Outlook is for central Virginia, west central Virginia and southeast West Virginia. .DAY ONE...Today and tonight. Heavy downpours this afternoon and tonight could lead to localized flooding. .DAYS TWO THROUGH SEVEN...Sunday through Friday. A prolonged period of moderate to heavy rain is possible Sunday through Monday. This rain may lead to minor flooding on streams and rivers. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The Roanoke radar (KFCX), 53 km away, was scanning. The volume nearest the first event began at 12:01 UTC.
13 flood, 2 heavy rain, 1 flash flood. Local standard time, as filed.
Storm total rainfall amounts of 5.16 and 5.33 inches were reported in Martinsville producing saturated soils that led to two downed trees on the mornings of the 25th and 26th. One tree was across Morningside Drive and another fell onto a house.
Old Kentucky Turnpike in Cedar Bluff was completely covered by flood waters from either Indian Creek or the Clinch River. Water flooded a basement causing an oil tank and hot water heater to overturn. Water was also reported up to the basement level of a home along Route 67 in Raven. The Clinch River gage at Richlands (RLRV2) crested at 10.68 feet at 0200 EST. Minor Flood stage is 10 feet.
Significant flooding affected much of Smyth County, especially in the Marion to Chilhowie corridor. Chilhowie had flooding in the town park with the Middle Fork Holston River rising all the way across the park to Railroad Avenue. The water also reached across Highway 107 between Berry Metals and McDonald’s leading to a closure of that section of road. Old vehicles were under water at Berry’s and the water covered part of McDonald’s parking lot in the front and the back. Water came up to a church next to the town park and the field next to the Smyth County Tourism Center flooded. Flood waters damaged houses on both ends of town and several businesses on Main Street. The Middle Fork of the Holston River was reported to be flooding near the intersection of VA Route 622 and US Highway 11, about 1 mile from exit 50 off Interstate 81. Flooding was reported on Old Lake Road with a driver stranded in a vehicle. Fox Valley Road was also reported to be flooded and closed from the Middle Fork of the Holston River.
The Middle Fork Holston River USGS gage at Seven Mile Ford (SMFV2) crested at 6.57 feet (preliminary) early on the 24th. This was the highest reading on this gage since November 2003. According to USGS data the discharge of 6800 cfs at this gage has annual chance exceedance between 0.1 and 0.2 (between 5-year and 10-year return period).
Wolf Creek was reported out of its banks along Eagles Road.
In the midst of ongoing longer-term flooding several additional roads were closed in the Chilhowie to Marion corridor after higher rainfall rates, up to 0.75 to 1.25 inches per hour moved across the area. Roads closed included Carlock Road north of Chilhowie, Fox Valley Road, Porter Valley Road, Old Lake Road and Scratch Gravel Road. This additional rainfall aggravated the ongoing flooding from several days of rain.
Up to 15 roads across Pittsylvania County were closed due to flooding or trees down.
Rainfall of 4.35 inches measured since midnight on April 24th.
Eagle Bottom Road in Fries was reported closed due to high water, possibly from Eagle Bottom Creek. Several days of persistent rain preceded the flooding.
Flooding was reported in several parts of Pulaski County including Peak Creek and along parts of the New River. The Peak Creek IFLOWS gage (PCRV2) crested at 8.5 feet and caused some flooding upstream of the town of Pulaski in the Kersey Bottom area near Melborn and Crescent Streets. The low-water crossing at Lottier Bottom was closed due to water across the roadway. Several other roads in the county were closed due to high water.
Cripple Creek flooded a portion of Apperson Drive.
Flooding occurred across much of Montgomery County closing numerous roads and forcing the closure of county schools for the day. The Roanoke River at Lafayette (LAAV2) crested at 8.85 feet (Minor Flood stage - 8 ft) and the South Fork Roanoke at Shawsville crested at 5.19 feet (Minor Flood stage - 5 ft). The New River at Radford (RDFV2) rose quickly to flood stage late on the 24th and crested at 16.78 feet (Flood stage - 14 feet), somewhere close to a 5-year return frequency (0.2 annual exceedance probability).
The forecast point on the Dan River at Danville (DVLV2) crested at 25.31 feet the highest stage since the New Years flood of January 1, 2007. This was just below the currently defined Major Flood Stage of 25.5 feet. Impacts were limited to some closed roads near the river and several buildings being partially flooded. The flood approached the 20-year return frequency (0.2 annual exceedance probability) according to USGS data.
Almost 20 different roads were closed or marked as dangerous across Wythe County.
Max Meadows Road was closed due to flooding from Reed Creek. The Reed Creek USGS gage at Grahams Forge (GRHV2) crested at 7.36 feet (Minor Flood Stage - 6.5 feet) at 1630 EST. According to USGS studies the peak flow of 7910 cfs at this gage is a little below the 0.1 annual exceedance probability or 10-year return frequency.
The Dan River flooded in Halifax County through South Boston. Several roads were closed by the Dan River and other flooded streams. The USGS river gage near Paces (PCEV2) crested above the Major flood category threshold (27 feet), reaching 29.14 feet late day on the 26th . This was the highest crest since September 1996 during Hurricane Fran and 6th highest crest at Paces with data back to about 1940. It was approximately a 25-year return frequency per the USGS or a .04 annual exceedance probability. At the South Boston river gage the crest of 30.25 was also above the Major flood threshold of 29 feet, the highest level since March 2003 and 9th highest on record. There was significant flooding impacts in South Boston with roads closed and several businesses affected. A car lot lost 15 cars due to flooding, and damage across Halifax County was estimated to be in the hundreds of thousands of dollars. There were two water rescues conducted in Halifax county during this event. On Wednesday evening (4/26) a lady drove into high waters crossing Old Cluster Springs Road and became stranded. Early Thursday (4/27) morning another individual drove a vehicle into floodwaters near the Hyco River bridge and was swept off Lowery Road. The driver was able to escape without injury.
Flooding developed along the Roanoke River with the river gage at Randolph (RNDV2) cresting just over 24 feet or Moderate Flood stage midday on the 26th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Virginia in 2017Every state in 2017This day in weather historyWarnings in Virginia, April 2017
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 694852, 686467, 686474, 686470, 687095, 694646, 694845, 686710, 694683, 686714, 694622, 694629, 694625, 686722, 694651, 694654.