After flash flooding developed across McDowell County on the 19th, new flooding occurred on the 20th as waves of showers produced an additional 1 to 2 inches fell in the Old Fort area, bringing total 3-day rainfall to 6 to 8 inches.
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 GSP wrote it up.
After flash flooding developed across McDowell County on the 19th, new flooding occurred on the 20th as waves of showers produced an additional 1 to 2 inches fell in the Old Fort area, bringing total 3-day rainfall to 6 to 8 inches.
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 Greenville-Spartanburg, SC wrote its last area forecast discussion before the first event at May 20, 10:50 AM EST, 10 minutes earlier.
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1150 AM EDT Wed May 20 2020
.SYNOPSIS...
A large upper low will linger over the Tennessee Valley Region today
and tonight, generating several rounds of moderate to heavy rain
across much of our region. This pattern has the potential to produce
significant rainfall and flooding over parts of the region. The low
will finally start to move away on Thursday and Thursday night. On
Friday, one more disturbance will move across the region. We should
see a return to more typical late spring weather over the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 1150 AM EDT Wednesday: Minor adjustments made to temperatures
coincide with latest trends as the rest of the near term forecast
remains on track. A Flash Flood Watch remains in effect for the area
and flood warnings are currently in effect. Please see Hydrology
section below for more information regarding potential impacts from
excessive rain expected. There have already been a handful of
reports of trees down across the area due to the combination of
saturated soils and gusty winds (below advisory criteria). Please
note, this trend is expected to continue through today and tonight.
Also, a Public Information Statement has been issued to highlight
the increasing threat for landslides and debris flows across
portions of the mountains and foothills today through early Thursday
morning. Please see this product for more information.
As expected, moderate to heavy rain showers with a few embedded
thunderstorms continue to move NNE across the area per latest radar
imagery. Current temperatures range from the low to mid 50s.
Previous discussion: In coordination with WPC wrt the latest fcst
QPF, portions of our CWA are now under a High Risk for excessive
rainfall for today and tonight. The wet and unsettled weather
pattern will continue to bring waves of showers and a few
thunderstorms thru the near-term period as a large h5 low spins over
the TN Valley with a slight move eastward expected today. At the
sfc, the latest analysis depicts a fairly weak sfc low near the area
with a nearly stationary bndy located right over the CWA. With
plenty of available moisture in place along with some limited
instability and shear, we can't rule out a few thunderstorms
becoming stronger this afternoon (mainly across the Upstate). The
primary threat will be damaging winds with an isolated tornado also
possible. Otherwise, the main story will be the ongoing flood
threat, with moderate to heavy downpours at times and training of
storms. Since Monday, some areas have already received 3 to 6 inches
of rainfall, with a few locations approaching 7 inches. With the
hybrid wedge remaining in place, temperatures will stay well below
normal again today, with highs struggling to reach the low 60s
across the lower terrain.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 321 AM EDT Wednesday: The model guidance shows the cutoff
low finally but slowly on the move away from the fcst area, altho
we will remain under the influence of its cyclonic flow. More
importantly, at daybreak on Thursday, the plume of tropical moisture
will also be on the move across the western Piedmont/foothills of
NC. Unfortunately, this might be too late, and one might anticipate
the Flash Flood Watch to be extended over parts of the fcst area
through the daylight hours on Thursday to account for what looks
like an ongoing threat at least over the area east of Highway
321 in the morning. Very high precip probs will be maintained in
that area, and across the rest of the mtns as well as wraparound
moisture/precip remain across that region well into the day. We
should finally see the threat wane late Thursday as the mid/upper
level dry air wraps in across the rest of the fcst area while the
upper low moves toward the OH Valley. Temps should rebound but
remain below normal. On Thursday night, we might finally get a
break with the forcing having exited to the northeast, so precip
probs tail off considerably, but not entirely. Friday looks like
yet another busy day, what with so much lingering moisture to work
with. The guidance shows a short wave coming through an upstream
ridge Thursday night and then getting entrained into the cyclonic
flow around the departing upper low on Friday. That scenario brings
this forcing overhead during peak heating, which would support
numerous showers/storms across the mtns/foothills and a chance
everywhere else. Fortunately, buoyancy appears to be rather limited,
so we do NOT appear to have an appreciable chance at strong/severe
storms. Temps should climb back to normal. Finally, in the wake of
this short wave Friday night and the upper low having moved even
farther away, dare we say that we might start to briefly dry out
after midnight? One can hope at that point.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 140 AM EDT Wednesday: We are still on track for a weather
regime change once we finally get rid of the old upper low that
has plagued our region for the better part of the week thus
far. Altho the models differ in their placement of the upper low
Saturday morning, the effect is the same, that being an upper
ridge building in from the west to bring back our springtime. The
models are in general agreement that once the upper low moves
away, the pattern will reamplify with a ridge axis building over
the southeast/Carolinas/upper OH Valley regions. We are going
to feel this pattern as something almost summerlike because of
the humidity that will remain relatively high, thanks to all the
water that will have been dumped across our region this week, and
temps that should make it well into the 80s over the weekend. This
pattern will also support mainly diurnal showers and thunderstorms
through the medium range period. The precip probs are expected to be
above climo for the weekend as at least one weak short wave moves
over the region. We may drop back to mainly mtn convection early
next week if the ridge cuts off into an upper level anticyclone
and depending where the center of the anticyclone is located. The
building upper anticyclone may support a building sfc high off the
Canadian Maritimes that ridges all the way back down the east side
of the mtns, which would moderate the temps somewhat. Altho the
fcst right now shows temps dropping back toward climo for early
next week, there is a good chance this is underdone if we don't
develop or maintain a connection to that cooler sfc high.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and Elsewhere: With the hybrid wedge firmly in place, IFR
conditions are expected to continue thru the 12z TAF period. Shower
activity has increased across the Upstate sites and KAVL over the
past few hours and this round of precip will likely continue for
a more more hours. The model guidance has been trending downward
wrt instability for today/tonight, especially over the NC sites.
As such, I removed any mention of thunder for KCLT, KHKY, and KAVL,
and kept a VCTS for KGSP, KGMU, and KAND beginning around 14z. As
has been the case for the past couple of days, visby will likely
bounce around quite a bit thru the taf period as bands of precip
continue to move across the fcst area. Otherwise, winds will remain
out of the NE thru the period with some low-end gusts expected over
most sites.
Outlook: Unsettled weather and associated restrictions will continue
well into Thursday before improving by the weekend, however diurnally
driven SHRA/TSRA will be possible over the weekend.
Confidence Table...
15-21Z 21-03Z 03-09Z 09-12Z
KCLT Med 70% High 95% High 83% High 96%
KGSP High 90% High 95% High 86% Med 66%
KAVL High 83% High 91% High 91% Low 57%
KHKY High 81% High 93% High 95% High 96%
KGMU High 88% High 95% High 83% High 88%
KAND Med 76% Med 77% High 88% Med 77%
The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables are available at
the following link:
www.weather.gov/gsp/aviation
&&
.HYDROLOGY...
Very wet near-term antecedent conditions are setting the stage
for a hydrologically active Wednesday with widespread forecasted
rainfall of 2-4+" expected over saturated upper soils following
several rounds of heavy rain since Monday. The heavy rainfall
already observed, exceeding 5 inches in some locations along and
near the Blue Ridge Escarpment, has caused significant rises on
area stream. While most small streams have receded, flows remain
elevated heading into Wednesday. Though much of the area was dry
over the two weeks leading up to this event, the entire region
has seen a wet winter and early spring with above-normal rainfall.
Given these antecedent conditions and forecasted rainfall, WPC's
Moderate Risk and a High Risk for excessive rainfall today is well
placed and warranted.
With a lower threshold for excessive runoff and embedded rainfall
rates exceeding 3 inches per hour within bands of training
shower/convective activity on Wednesday, new rapid stream rises and
higher crests will be easier to achieve with any heavy rainfall that
occurs for the remainder of this multi-phased event. Therefore,
confidence is increasing that widespread Minor flooding will occur,
especially along the Blue Ridge Escarpment and adjacent foothills
of North and South Carolina during the day on Wednesday and near
the Charlotte Metro area later Wednesday. Isolated to scattered
areas of more significant (Moderate) flooding potentially impacting
several homes and businesses are likely, especially along and
adjacent to the Escarpment from Henderson and Polk counties north
to Avery and Caldwell counties, but such impacts cannot be ruled
out further east and south into the Piedmont, especially near
urban areas, including Charlotte.
As always, it will take many hours for streams to rise, crest, and
recede so flooding could persist well after the rainfall ends.
Larger streams will be the last to respond and recede from
excessive runoff; therefore, rivers like the Broad, Catawba,
and SF Catawba may see flooding persist well into Thursday.
Moderate flooding along these mainstem rivers, which includes
structural flooding, is possible so it will be important to monitor
forecasts (https:/water.weather.gov/ahps2/forecasts.php?wfo=gsp)
and Warnings for the latest information if conditions deteriorate.
Given the potential for high rainfall rates and event-total (since
Monday) rainfall amounts exceeding 10 inches in isolated locations
along and adjacent to the Escarpment, the threat for landslides is
also increasing. Residents in areas prone to landslides are urged
to review the GSP Public Information Statement for preparedness
information and be prepared to act if a Flash Flood Warning is
issued for your area.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...Flash Flood Watch through Thursday morning for NCZ033-035>037-
049-050-053-056-057-064-065-068>072-082-501>510.
SC...Flash Flood Watch through Thursday morning for SCZ002-003-
005>010-013-014.
&&
SYNOPSIS...PM
NEAR TERM...JPT/12
SHORT TERM...PM
LONG TERM...PM
AVIATION...JPT
HYDROLOGY...GSPHazardous Weather Outlook National Weather Service Greenville-Spartanburg SC 509 AM EDT Wed May 20 2020 NCZ033-035>037-049-050-053-056-057-064-065-068>072-082-501>510- SCZ002-003-005>010-013-014-210915- Avery-Alexander-Iredell-Davie-Yancey-Mitchell-Buncombe-Catawba-Rowan- Transylvania-Henderson-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus- Union NC-Caldwell Mountains-Greater Caldwell-Burke Mountains- Greater Burke-McDowell Mountains-Eastern McDowell- Rutherford Mountains-Greater Rutherford-Polk Mountains-Eastern Polk- Pickens Mountains-Greenville Mountains-Greater Pickens- Greater Greenville-Spartanburg-Cherokee-York-Anderson-Union SC- Chester- 509 AM EDT Wed May 20 2020 ...FLASH FLOOD WATCH IN EFFECT THROUGH THURSDAY MORNING... This Hazardous Weather Outlook is for the western Piedmont, foothills, and parts of the North Carolina mountains, and parts of upstate South Carolina. .DAY ONE...Today and tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Flash Flood Watch. In addition to the heavy rainfall threat, isolated thunderstorms are possible through tonight. The storms that develop will produce cloud to ground lightning, torrential downpours, and wind gusts capable of knocking down trees weakened by the heavy rain and saturated soil. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Flash Flood Watch. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed. Please relay any information about observed severe weather to the NWS while following all local, state, and CDC guidelines. GAZ010-NCZ048-051-052-058-059-062-063-210915- Rabun-Madison-Swain-Haywood-Graham-Northern Jackson-Macon- Southern Jackson- 509 AM EDT Wed May 20 2020 This Hazardous Weather Outlook is for northeast Georgia and western North Carolina. .DAY ONE...Today and tonight. Isolated thunderstorms are possible through tonight. The main threats from these thunderstorms will be heavy rainfall and cloud to ground lightning. Some locations could experience minor flooding where numerous showers and storms occur. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. Periods of showers and storms could persist into Thursday morning. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed. Please relay any information about observed severe weather to the NWS while following all local, state, and CDC guidelines. GAZ017-018-026-028-029-SCZ001-004-011-012-019-210915- Habersham-Stephens-Franklin-Hart-Elbert-Oconee Mountains- Greater Oconee-Abbeville-Laurens-Greenwood- 509 AM EDT Wed May 20 2020 This Hazardous Weather Outlook is for northeast Georgia and upstate South Carolina. .DAY ONE...Today and tonight. Numerous of showers and thunderstorms are expected through today and into tonight. Periods of heavy rain can be expected, perhaps enough to cause flooding of poor drainage areas and rapid rises on streams and creeks. Cloud to ground lightning can be expected in thunderstorms. A few of the storms could produce wind gusts strong enough to knock down a few trees that have been weakened by the heavy rain and saturated soil. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. No significant weather is expected. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed. Please relay any information about observed severe weather to the NWS while following all local, state, and CDC guidelines. PM
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
952 AM EDT WED MAY 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0930 AM FLASH FLOOD 6 N ANDERSON 34.60N 82.65W
05/20/2020 ANDERSON SC LAW ENFORCEMENT
DALRYMPLE RD NEAR THOMPSON RD FLOODED.
&&
17PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1027 AM EDT WED MAY 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0948 AM FLASH FLOOD 5 W GREENVILLE 34.85N 82.46W
05/20/2020 GREENVILLE SC LAW ENFORCEMENT
ROADWAY WASHED OUT AT GETHSEMANE DR NEAR SC-124.
&&
17PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1032 AM EDT WED MAY 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0955 AM FLASH FLOOD 6 ESE TIGERVILLE 35.04N 82.27W
05/20/2020 GREENVILLE SC LAW ENFORCEMENT
WATER OVER FORRESTER RD NEAR HWY 14.
&&
17PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1035 AM EDT WED MAY 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1000 AM FLASH FLOOD 5 NNW GREENVILLE 34.90N 82.42W
05/20/2020 GREENVILLE SC LAW ENFORCEMENT
PARKER RD FLOODED AT US-276.
&&
17PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1037 AM EDT WED MAY 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1000 AM FLASH FLOOD 5 SSE TIGERVILLE 35.01N 82.32W
05/20/2020 GREENVILLE SC LAW ENFORCEMENT
BULLS RD FLOODED NEAR GROCE MEADOW RD.
&&
17PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1104 AM EDT WED MAY 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1040 AM FLASH FLOOD 1 ENE TAYLORS 34.92N 82.29W
05/20/2020 GREENVILLE SC LAW ENFORCEMENT
AIKEN CHAPEL RD IMPASSBLE DUE TO FLOODING NEAR THE ENOREE
RIVER.
&&
17The national radar mosaic for the moment the first event began.
2 flood. Local standard time, as filed.
Emergency manager reported flooding redeveloped along Mill Creek in the Old Fort area after an additional 1 to 2 inches of rain fell on top of saturated ground and with the creek already in a high flow situation. Simmons Rd was flooded as was Westerman St at Salisbury Ave.
For the second day in a row, a stream gauge on the Catawba River near Pleasant Gardens exceeded established minor flood stage, indicating inundation of several campgrounds along the river between Old Fort and Marion. Two to four inches of rain fell across the area on the 20th, bringing the two-day total to 5 to 8 inches across the Catawba basin.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in North Carolina in 2020Every state in 2020This day in weather historyWarnings in North Carolina, May 2020
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: 897800, 897817.