Alert archive / Virginia / Flash Flood Watches in 2021

Flash Flood Watch 4, NWS Blacksburg, VA

June 11, 2021Amherst County, Campbell County, City of Lynchburg, Virginia

NWS Blacksburg, VA issued this flash flood watch at Jun 11, 2021, 10:19 PM EDT for Amherst County, Campbell County, City of Lynchburg, Virginia. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Jun 11, 2021, 10:19 PM EDT (02:19 UTC)
Expired: Jun 12, 2021, 1:18 AM EDT
In force: 3 hr
Issued by: NWS Blacksburg, VA
Flood severity: None

Counties Amherst County, VA, Campbell County, VA, City of Lynchburg, VA

The radar

The Roanoke radar (KFCX), 110 km from the middle of the area, began a volume at 02:22 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.

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 2.3 hours before the alert went out and 40 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 432 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 660 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 11 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

024 
WGUS61 KRNK 120219
FFARNK

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Blacksburg VA
1019 PM EDT Fri Jun 11 2021

VAZ035-045-121030-
/O.NEW.KRNK.FF.A.0004.210612T0219Z-210612T1500Z/
/00000.0.DM.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Amherst-Campbell-
Including the cities of Amherst and Lynchburg
1019 PM EDT Fri Jun 11 2021

...FLASH FLOOD WATCH FOR THE COLLEGE LAKE DAM ON THE BLACKWATER 
CREEK IS IN EFFECT THROUGH SATURDAY MORNING...

The National Weather Service in Blacksburg has issued a

* Flash Flood Watch for...
  A Dam or Levee Failure on the BLACKWATER CREEK below COLLEGE LAKE 
  DAM in a portion of central Virginia, including the following 
  areas, Amherst and Campbell.

* Through Saturday morning

* At 1019 PM EDT, dam operators reported that water is rapidly 
  rising behind the COLLEGE LAKE DAM on the BLACKWATER CREEK.

* This impacts parts of LYNCHBURG CITY. Areas downstream from the 
  COLLEGE LAKE DAM along the BLACKWATER CREEK should be prepared for 
  flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

BMG

1 follow-up statement

635 
WGUS61 KRNK 120518
FFARNK

Flood Watch
National Weather Service Blacksburg VA
118 AM EDT Sat Jun 12 2021

VAZ035-045-120630-
/O.CAN.KRNK.FF.A.0004.000000T0000Z-210612T1500Z/
/00000.0.DM.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Amherst-Campbell-
Including the cities of Amherst and Lynchburg
118 AM EDT Sat Jun 12 2021

...FLASH FLOOD WATCH FOR THE POTENTIAL FAILURE OF COLLEGE LAKE DAM 
ON THE BLACKWATER CREEK IS CANCELLED...

The Flash Flood Watch for a portion of central Virginia, including 
the following areas, Amherst and Campbell has been cancelled.

Water at the dam had receded. Flooding is no longer expected to pose 
a threat. Please continue to heed remaining road closures.

$$

AS

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 11, 8:09 PM EDT	Special Weather Statement	RNK	Henry	36 min
Jun 11, 8:27 PM EDT	Areal Flood Warning	RNK	Amherst, Bedford, Campbell, City of Lynchburg	5 hr
Jun 12, 8:16 AM EDT	Special Weather Statement	RNK	City of Galax	44 min
Jun 12, 3:14 PM EDT	Special Weather Statement	RNK	City of Galax	31 min
Jun 12, 3:30 PM EDT	Areal Flood Advisory	RNK	Carroll	3 hr
Jun 12, 4:50 PM EDT	Special Weather Statement	RNK	Grayson	25 min
Jun 12, 5:16 PM EDT	Areal Flood Advisory	RNK	Grayson	3 hr

Nearby

Flash Flood Watches in Virginia, 2021 Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.