Alert archive / North Carolina / Flash Flood Warnings in 2021
Flash Flood Warning 29, NWS Blacksburg, VA
NWS Blacksburg, VA issued this flash flood warning at Aug 17, 2021, 7:13 PM EDT for Watauga County, North Carolina. It was in force for 8 hr. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Aug 17, 2021, 7:13 PM EDT (23:13 UTC)
- Expired
- Aug 18, 2021, 2:54 AM EDT
- In force
- 8 hr
- Issued by
- NWS Blacksburg, VA
- Area
- Storm-based polygon
- Flood severity
- None
County Watauga County, NC
The radar
The Knoxville radar (KMRX), 151 km from the middle of the area, began a volume at 23:13 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 17, 11:10 PM EDT | FLASH FLOOD | 1 Nw Boone, NC | MULTIPLE IMAGES AND VIDEOS OF FLASH FLOODING ONGOING IN BOONE WITH MULTIPLE VEHICLES WITH WATER ABOVE THEIR TIRE LINES. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 11.2 hours before the alert went out and 164 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 522 J/kg
- Mixed-layer CIN
- -5 J/kg
- Mixed-layer LCL
- 593 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 77 m²/s²
- 0-3 km storm-relative helicity
- 99 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.9
The text
As transmitted.
439
WGUS51 KRNK 172313
FFWRNK
NCC189-180400-
/O.NEW.KRNK.FF.W.0029.210817T2313Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Blacksburg VA
713 PM EDT Tue Aug 17 2021
The National Weather Service in Blacksburg has issued a
* Flash Flood Warning for...
Watauga County in northwestern North Carolina...
* Until midnight EDT.
* At 713 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1.5 and 3 inches of
rain have fallen over the last 24 hours. The expected rainfall
rate between now and 10:00 PM is expected to range from 1.0 to as
much as 5 inches in 1 hour. Additional rainfall amounts of 2 to 4
inches are possible in the warned area...resulting in potential
rainfall totals of 3.5 to 7.0 inches. Flash flooding is expected
to begin shortly.
HAZARD...Flash flooding caused by excessive tropical rainfall.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Boone... Blowing Rock...
Beech Mountain... Sugar Grove...
Foscoe... Todd...
Deep Gap...
This includes the following locations...
Appalachian State University.
This includes the following streams and drainages...
Brushy Fork, Elk Creek, George Gap Branch, Beech Creek, Beaverdam
Creek, Flat Branch, Craborchard Creek, Cove Creek, Fall Creek,
Dugger Creek and Dutch Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
&&
LAT...LON 3627 8156 3624 8148 3620 8145 3614 8150
3611 8155 3611 8167 3611 8181 3617 8183
3619 8186 3619 8189 3622 8191 3626 8189
3629 8192 3634 8186 3636 8179 3634 8176
3634 8170 3638 8173 3639 8173 3635 8164
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2.5-5 INCHES IN 1 HOUR
$$
115 follow-up statements
879
WGUS71 KRNK 180052
FFSRNK
Flash Flood Statement
National Weather Service Blacksburg VA
852 PM EDT Tue Aug 17 2021
NCC189-180400-
/O.CON.KRNK.FF.W.0029.000000T0000Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Watauga NC-
852 PM EDT Tue Aug 17 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL MIDNIGHT EDT TONIGHT
FOR WATAUGA COUNTY...
At 852 PM EDT, Doppler radar indicated an area of heavy rain,
embedded with thunderstorms across the warned area. Between 2 and 4
inches of rain have fallen over the last 24 hours. The rainfall rate
between now and 10:00 PM is expected to be 2.5 to 4 inches in 1
hour. Additional rainfall amounts of 1 to 3 inches are possible in
the warned area. This will bring 24 hour rainfall totals into the
3.5 to 7.0 inch range. Flash flooding is ongoing or expected to
begin shortly.
HAZARD...Flash flooding caused by thunderstorms and tropical
rainfall.
SOURCE...Radar and Rain Gage reports.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Boone... Blowing Rock...
Beech Mountain... Sugar Grove...
Foscoe... Todd...
Deep Gap...
This includes the following locations...
Appalachian State University.
This includes the following streams and drainages...
Brushy Fork, Elk Creek, George Gap Branch, Beech Creek, Beaverdam
Creek, Flat Branch, Craborchard Creek, Cove Creek, Fall Creek,
Dugger Creek and Dutch Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
&&
LAT...LON 3627 8156 3624 8148 3620 8145 3614 8150
3611 8155 3611 8167 3611 8181 3617 8183
3619 8186 3619 8189 3622 8191 3626 8189
3629 8192 3634 8186 3636 8179 3634 8176
3634 8170 3638 8173 3639 8173 3635 8164
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2.5-4 INCHES IN 1 HOUR
$$
11534
WGUS71 KRNK 180227
FFSRNK
Flash Flood Statement
National Weather Service Blacksburg VA
1027 PM EDT Tue Aug 17 2021
NCC189-180400-
/O.CON.KRNK.FF.W.0029.000000T0000Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Watauga NC-
1027 PM EDT Tue Aug 17 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL MIDNIGHT EDT TONIGHT
FOR WATAUGA COUNTY...
At 1027 PM EDT, Automated rain gauges indicated that between 3 and 6
inches of rain have fallen across Watauga County over the last 24
hours, three inches of that rain, falling between 8:00 PM and 10:00
PM this evening. Flash flooding is ongoing or expected to begin
shortly due to the runoff from this excessive rainfall.
HAZARD...Flash flooding caused by thunderstorms and tropical
rainfall.
SOURCE...Radar and automated gauges.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Boone... Blowing Rock...
Beech Mountain... Sugar Grove...
Foscoe... Todd...
Deep Gap...
This includes the following locations...
Appalachian State University.
Watch for mudslides and debris on area highways. This rain is
coming from a tropical system which not only causes flooding, but
also results in falling trees from the heavy water loading, and
softening of the ground.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles, and especially at night when it is harder
to see water on the road and debris in the highway.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
&&
LAT...LON 3627 8156 3624 8148 3620 8145 3614 8150
3611 8155 3611 8167 3611 8181 3617 8183
3619 8186 3619 8189 3622 8191 3626 8189
3629 8192 3634 8186 3636 8179 3634 8176
3634 8170 3638 8173 3639 8173 3635 8164
FLASH FLOOD...RADAR AND GAUGE INDICATED
$$
PM916
WGUS51 KRNK 180311
FFWRNK
NCC189-180700-
/O.EXT.KRNK.FF.W.0029.000000T0000Z-210818T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Blacksburg VA
1111 PM EDT Tue Aug 17 2021
The National Weather Service in Blacksburg has extended the
* Flash Flood Warning for...
Watauga County in northwestern North Carolina...
* Until 300 AM EDT.
* At 1111 PM EDT, Automated rain gauges indicated that between 3 and
6 inches of rain have fallen across Watauga County over the last
24 hours, three inches of that rain, falling between 8:00 PM and
10:00 PM this evening. Flash flooding is ongoing and may continue
into the late night. The warning has been extended until 3:00 AM
to account for a continuation of the runoff from this excessive
rainfall.
HAZARD...Flash flooding caused by thunderstorms and tropical
rainfall.
SOURCE...Radar and Rain Gage reports.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Boone... Blowing Rock...
Sugar Grove... Deep Gap...
Foscoe... Todd...
This includes the following locations...
Appalachian State University.
Watch for mudslides and debris on area highways. This rain is
coming from a tropical system which not only causes flooding, but
also results in falling trees from the heavy water loading, and
softening of the ground.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
When it is safe to do so, please send your reports of flooding,
including mudslides or flooded roads, to the National Weather
Service by calling toll free at 1...8 6 6...2 1 5...4 3 2 4. Reports
and pictures can also be shared on the National Weather Service
Blacksburg Facebook page and on Twitter.
&&
LAT...LON 3627 8156 3624 8148 3620 8145 3614 8150
3611 8155 3611 8167 3611 8181 3617 8183
3619 8186 3619 8189 3622 8191 3626 8189
3629 8192 3634 8186 3636 8179 3634 8176
3634 8170 3638 8173 3639 8173 3635 8164
FLASH FLOOD...RADAR AND GAUGE INDICATED
$$
PM452
WGUS71 KRNK 180500
FFSRNK
Flash Flood Statement
National Weather Service Blacksburg VA
100 AM EDT Wed Aug 18 2021
NCC189-180700-
/O.CON.KRNK.FF.W.0029.000000T0000Z-210818T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Watauga NC-
100 AM EDT Wed Aug 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 3 AM EDT EARLY THIS
MORNING FOR WATAUGA COUNTY...
At 100 AM EDT, Doppler radar and automated rain gauges indicated
that heavy rain has exited the area this evening, leaving only light
rain showers across the county. However, runoff from between 3 and 6
inches of rain that fell this evening continues to collect in area
rivers and streams. Flash flooding is already occurring, and will
continue through at least 3 am. Automated river gauges indicate that
the Watauga River is rising quickly this morning, with minor
flooding ongoing.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar and automated gauges.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Boone... Blowing Rock...
Beech Mountain... Sugar Grove...
Foscoe... Todd...
Deep Gap...
This includes the following locations...
Appalachian State University.
This includes the following streams and drainages...
Brushy Fork, Elk Creek, George Gap Branch, Beech Creek, Beaverdam
Creek, Flat Branch, Crab Orchard Creek, Cove Creek, Fall Creek,
Dugger Creek and Dutch Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
When it is safe to do so, please send your reports of flooding,
including mudslides or flooded roads, to the National Weather
Service by calling toll free at 1...8 6 6...2 1 5...4 3 2 4. Reports
and pictures can also be shared on the National Weather Service
Blacksburg Facebook page and on Twitter.
&&
LAT...LON 3627 8156 3624 8148 3620 8145 3614 8150
3611 8155 3611 8167 3611 8181 3617 8183
3619 8186 3619 8189 3622 8191 3626 8189
3629 8192 3634 8186 3636 8179 3634 8176
3634 8170 3638 8173 3639 8173 3635 8164
FLASH FLOOD...RADAR AND GAUGE INDICATED
$$
16360
WGUS71 KRNK 180654
FFSRNK
Flash Flood Statement
National Weather Service Blacksburg VA
254 AM EDT Wed Aug 18 2021
NCC189-180704-
/O.CAN.KRNK.FF.W.0029.000000T0000Z-210818T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Watauga NC-
254 AM EDT Wed Aug 18 2021
...FLASH FLOOD WARNING FOR WATAUGA COUNTY HAS BEEN REPLACED WITH A
FLOOD WARNING...
LAT...LON 3627 8156 3624 8148 3620 8145 3614 8150
3611 8155 3611 8167 3611 8181 3617 8183
3619 8186 3619 8189 3622 8191 3626 8189
3629 8192 3634 8186 3636 8179 3634 8176
3634 8170 3638 8173 3639 8173 3635 8164
$$
16The office that day
Everything else NWS Blacksburg, VA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 17, 3:37 AM EDT | Flash Flood Watch | RNK | Alleghany, Ashe, Surry, Watauga, Wilkes | 24 hr |
| Aug 17, 11:48 AM EDT | Tornado Warning | RNK | Wilkes | 42 min |
| Aug 17, 12:35 PM EDT | Tornado Warning | RNK | Wilkes, Yadkin | 40 min |
| Aug 17, 12:46 PM EDT | Special Weather Statement | RNK | Wilkes | 44 min |
| Aug 17, 1:19 PM EDT | Tornado Warning | RNK | Wilkes | 41 min |
| Aug 17, 1:48 PM EDT | Tornado Warning | RNK | Alleghany, Wilkes | 42 min |
| Aug 17, 1:58 PM EDT | Special Weather Statement | RNK | Alleghany, Caswell, Rockingham, Stokes, Surry, Yadkin | 32 min |
| Aug 17, 2:18 PM EDT | Tornado Warning | RNK | Caswell | 32 min |
| Aug 17, 2:43 PM EDT | Tornado Warning | RNK | Rockingham, Stokes | 32 min |
| Aug 17, 4:35 PM EDT | Special Weather Statement | RNK | Surry | 25 min |
| Aug 17, 5:05 PM EDT | Special Weather Statement | RNK | Alleghany | 40 min |
| Aug 17, 6:50 PM EDT | Special Weather Statement | RNK | Watauga | 25 min |
| Aug 17, 7:54 PM EDT | Special Weather Statement | RNK | Ashe | 36 min |
Nearby
Flash Flood Warnings in North Carolina, 2021Every flash flood warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.