Alert archive / Virginia / Flash Flood Watches in 2013

Flash Flood Watch 7, NWS Blacksburg, VA

July 2, 201337 counties in Virginia; 9 counties in North Carolina; Mercer County, Monroe County, Summers County, West Virginia

NWS Blacksburg, VA issued this flash flood watch at Jul 2, 2013, 4:19 AM EDT for 37 counties in Virginia; 9 counties in North Carolina; Mercer County, Monroe County, Summers County, West Virginia. It took effect at Jul 2, 2013, 5:00 AM EDT. It was in force for 5 days.

The area

The counties it named.

The facts

Issued: Jul 2, 2013, 4:19 AM EDT (08:19 UTC)
In effect from: Jul 2, 2013, 5:00 AM EDT
Expired: Jul 6, 2013, 8:00 PM EDT
In force: 5 days
Issued by: NWS Blacksburg, VA
Flood severity: None

All 49 counties

Alleghany County, NC, Ashe County, NC, Caswell County, NC, Rockingham County, NC, Stokes County, NC, Surry County, NC, Watauga County, NC, Wilkes County, NC, Yadkin County, NC, Alleghany County, VA, Amherst County, VA, Appomattox County, VA, Bath County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Buckingham County, VA, Campbell County, VA, Carroll County, VA, Charlotte County, VA, City of Buena Vista, VA, City of Covington, VA, City of Danville, VA, City of Galax, VA, City of Lexington, VA, City of Lynchburg, VA, City of Martinsville, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Floyd County, VA, Franklin County, VA, Giles County, VA, Grayson County, VA, Halifax County, VA, Henry County, VA, Montgomery County, VA, Patrick County, VA, Pittsylvania County, VA, Pulaski County, VA, Roanoke County, VA, Rockbridge County, VA, Smyth County, VA, Tazewell County, VA, Wythe County, VA, Mercer County, WV, Monroe County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 10 km from the middle of the area, began a volume at 08:19 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, 8.3 hours before the alert went out and 61 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: 570 J/kg
Mixed-layer CIN: -3 J/kg
Mixed-layer LCL: 792 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 139 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 3.7

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, 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 this flash flood watch went out at Jul 2, 4:17 AM EDT, 2 minutes earlier.

Area forecast discussion, Jul 2, 4:17 AM EDT, 2 minutes before

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Hazardous weather outlook, Jul 1, 3:52 PM EDT, 12 hours 27 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 1, 9:26 PM EDT	Special Weather Statement	RNK	Bland, Grayson, Smyth, Tazewell	64 min
Jul 2, 4:55 AM EDT	Special Weather Statement	RNK	Carroll, Wythe, City of Galax	80 min
Jul 2, 6:33 AM EDT	Special Weather Statement	RNK	Grayson	72 min
Jul 2, 10:57 AM EDT	Special Weather Statement	RNK	Carroll	48 min
Jul 2, 12:29 PM EDT	Special Weather Statement	RNK	Halifax	31 min
Jul 2, 12:31 PM EDT	Areal Flood Advisory	RNK	Carroll, Floyd, Montgomery, Roanoke, City of Roanoke, City of Salem	3 hr
Jul 2, 1:04 PM EDT	Special Weather Statement	RNK	Halifax	26 min
Jul 2, 1:19 PM EDT	Special Weather Statement	RNK	Franklin	86 min
Jul 2, 2:51 PM EDT	Areal Flood Advisory	RNK	Grayson	3 hr
Jul 2, 3:12 PM EDT	Areal Flood Advisory	RNK	Amherst, Bedford, Rockbridge, City of Buena Vista, City of Lexington	3 hr
Jul 2, 6:20 PM EDT	Areal Flood Advisory	RNK	Carroll, Floyd, Franklin, Patrick, Roanoke, City of Roanoke	3 hr
Jul 1, 8:00 PM EDT	Special Weather Statement	RNK	Ashe, Watauga	60 min
Jul 1, 9:10 PM EDT	Areal Flood Advisory	RNK	Watauga	3 hr
Jul 1, 10:38 PM EDT	Areal Flood Advisory	RNK	Alleghany, Ashe, Watauga, Wilkes	3 hr
Jul 2, 12:49 AM EDT	Areal Flood Warning	RNK	Ashe, Watauga	4 hr

Nearby

Flash Flood Watches in Virginia, 2013 Flash Flood Watches in North Carolina, 2013 Flash Flood Watches in West Virginia, 2013 Every flash flood watch in 2013

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.