Alert archive / Virginia / Flash Flood Watches in 2015

Flash Flood Watch 6, NWS Blacksburg, VA

July 13, 201526 counties in Virginia; Alleghany County, Ashe County, Watauga County, North Carolina; 4 counties in West Virginia

NWS Blacksburg, VA issued this flash flood watch at Jul 13, 2015, 3:36 PM EDT for 26 counties in Virginia; Alleghany County, Ashe County, Watauga County, North Carolina; 4 counties in West Virginia. It took effect at Jul 13, 2015, 6:00 PM EDT. It was in force for 14 hr.

The area

The counties it named.

The facts

Issued: Jul 13, 2015, 3:36 PM EDT (19:36 UTC)
In effect from: Jul 13, 2015, 6:00 PM EDT
Expired: Jul 14, 2015, 7:37 AM EDT
In force: 14 hr
Issued by: NWS Blacksburg, VA
Flood severity: None

All 33 counties

Alleghany County, NC, Ashe County, NC, Watauga County, NC, Alleghany County, VA, Bath County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Carroll County, VA, City of Buena Vista, VA, City of Covington, VA, City of Galax, VA, City of Lexington, 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, Montgomery County, VA, Patrick County, VA, Pulaski County, VA, Roanoke County, VA, Rockbridge County, VA, Smyth County, VA, Tazewell County, VA, Wythe County, VA, Greenbrier County, WV, Mercer County, WV, Monroe County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 28 km from the middle of the area, began a volume at 19:36 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 12:00Z, 7.6 hours before the alert went out and 87 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: 377 J/kg
Mixed-layer CIN: -41 J/kg
Mixed-layer LCL: 669 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 131 m²/s²
0-3 km storm-relative helicity: 119 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 13, 1:57 PM EDT, 1 hour 39 minutes earlier.

Area forecast discussion, Jul 13, 1:57 PM EDT, 1 hour 39 minutes before

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Hazardous weather outlook, Jul 13, 5:06 AM EDT, 10 hours 30 minutes before

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In the hours before

Local storm report, Jul 13, 9:39 AM EDT, 5 hours 57 minutes before

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Local storm report, Jul 13, 3:23 PM EDT, 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
323 PM EDT MON JUL 13 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0230 AM     DEBRIS FLOW      2 SW NARROWS            37.31N 80.84W
07/13/2015                   GILES              VA   TRAINED SPOTTER

            MUDSLIDE NEAR THE ROAD ON STATE ROUTE 61, WOLF CREEK ROAD
            ABOUT 2.3 MILES SOUTHWEST OF NARROWS, VA.

&&

JMORROW

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 12, 9:45 PM EDT	Special Weather Statement	RNK	Craig, Franklin, Roanoke, City of Roanoke, City of Salem	60 min
Jul 12, 10:23 PM EDT	Areal Flood Advisory	RNK	Craig, Roanoke, City of Roanoke, City of Salem	112 min
Jul 12, 11:06 PM EDT	Special Weather Statement	RNK	Alleghany, Bedford, Botetourt, Craig, City of Covington, City of Roanoke and 1 more	54 min
Jul 12, 11:30 PM EDT	Special Weather Statement	RNK	Bland	60 min
Jul 13, 12:14 AM EDT	Special Weather Statement	RNK	Giles, Montgomery, Pulaski, City of Radford	61 min
Jul 13, 12:29 AM EDT	Areal Flood Advisory	RNK	Bedford, Botetourt, Franklin, Roanoke, City of Roanoke, City of Salem	3 hr
Jul 13, 1:01 AM EDT	Special Weather Statement	RNK	Franklin	59 min
Jul 13, 1:08 AM EDT	Special Weather Statement	RNK	Carroll, Floyd, Franklin	52 min
Jul 13, 1:17 AM EDT	Flash Flood Warning	RNK	Giles	3 hr
Jul 13, 1:39 AM EDT	Severe Thunderstorm Warning	RNK	Bedford, Franklin, Pittsylvania	42 min
Jul 13, 1:46 AM EDT	Special Weather Statement	RNK	Montgomery, Pulaski, City of Radford	44 min
Jul 13, 2:18 AM EDT	Special Weather Statement	RNK	Floyd, Patrick	57 min
Jul 13, 3:06 AM EDT	Areal Flood Advisory	RNK	Patrick	3 hr
Jul 13, 6:43 AM EDT	Areal Flood Advisory	RNK	Botetourt, Craig, Roanoke, City of Roanoke, City of Salem	4 hr
Jul 13, 5:29 PM EDT	Special Weather Statement	RNK	Smyth	46 min
Jul 13, 5:33 PM EDT	Severe Thunderstorm Warning	RNK	Smyth, Wythe	57 min
Jul 13, 5:39 PM EDT	Severe Thunderstorm Warning	RNK	Smyth, Tazewell	51 min
Jul 13, 6:17 PM EDT	Severe Thunderstorm Warning	RNK	Bland, Giles, Tazewell	58 min
Jul 13, 6:32 PM EDT	Severe Thunderstorm Warning	RNK	Pulaski, Smyth, Wythe	58 min
Jul 13, 6:52 PM EDT	Severe Thunderstorm Warning	RNK	Grayson	49 min
Jul 13, 6:55 PM EDT	Special Weather Statement	RNK	Pittsylvania	65 min
Jul 13, 6:59 PM EDT	Severe Thunderstorm Warning	RNK	Carroll, City of Galax	61 min
Jul 13, 7:04 PM EDT	Special Weather Statement	RNK	Amherst, Appomattox, Campbell, City of Buena Vista, City of Lynchburg	56 min
Jul 13, 7:09 PM EDT	Severe Thunderstorm Warning	RNK	Alleghany, Bath, Craig, Floyd, Montgomery, Patrick and 2 more	66 min
Jul 13, 7:30 PM EDT	Severe Thunderstorm Warning	RNK	Roanoke, City of Roanoke, City of Salem	60 min
Jul 13, 7:54 PM EDT	Severe Thunderstorm Warning	RNK	Appomattox, Campbell, Charlotte	36 min
Jul 13, 7:59 PM EDT	Severe Thunderstorm Warning	RNK	Bedford, Botetourt, Franklin, Henry, Patrick, City of Martinsville	61 min
Jul 13, 3:43 AM EDT	Special Weather Statement	RNK	Rockingham, Stokes	62 min
Jul 12, 10:46 PM EDT	Areal Flood Advisory	RNK	Greenbrier	119 min
Jul 12, 11:57 PM EDT	Flash Flood Warning	RNK	Mercer	3 hr
Jul 13, 3:01 AM EDT	Special Weather Statement	RNK	Greenbrier	59 min
Jul 13, 3:57 AM EDT	Flash Flood Warning	RNK	Greenbrier	4 hr
Jul 13, 6:25 PM EDT	Severe Thunderstorm Warning	RNK	Greenbrier, Monroe, Summers	65 min

Nearby

Flash Flood Watches in Virginia, 2015 Flash Flood Watches in West Virginia, 2015 Flash Flood Watches in North Carolina, 2015 Every flash flood watch in 2015

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.