Alert archive / Virginia / Flash Flood Watches in 2017

Flash Flood Watch 5, NWS Blacksburg, VA

October 23, 2017Carroll County, Grayson County, City of Galax, Virginia; Alleghany County, Ashe County, Watauga County, North Carolina

NWS Blacksburg, VA issued this flash flood watch at Oct 23, 2017, 10:46 AM EDT for Carroll County, Grayson County, City of Galax, Virginia; Alleghany County, Ashe County, Watauga County, North Carolina. It took effect at Oct 23, 2017, 2:00 PM EDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued: Oct 23, 2017, 10:46 AM EDT (14:46 UTC)
In effect from: Oct 23, 2017, 2:00 PM EDT
Expired: Oct 23, 2017, 8:00 PM EDT
In force: 6 hr
Issued by: NWS Blacksburg, VA
Flood severity: None

Counties Alleghany County, NC, Ashe County, NC, Watauga County, NC, Carroll County, VA, City of Galax, VA, Grayson County, VA

The radar

The Roanoke radar (KFCX), 99 km from the middle of the area, began a volume at 14:45 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

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 2.8 hours before the alert went out and 127 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 597 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 202 m²/s²
0-3 km storm-relative helicity: 259 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Oct 23, 7:52 AM EDT, 2 hours 54 minutes earlier.

Area forecast discussion, Oct 23, 7:52 AM EDT, 2 hours 54 minutes before

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Hazardous weather outlook, Oct 23, 5:30 AM EDT, 5 hours 16 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
Oct 23, 3:07 PM EDT	Special Weather Statement	RNK	Bland, Carroll, Grayson, Pulaski, Smyth, Tazewell and 2 more	83 min
Oct 23, 4:27 PM EDT	Special Weather Statement	RNK	Craig, Giles, Montgomery, Pulaski, City of Radford	108 min
Oct 23, 4:40 PM EDT	Special Weather Statement	RNK	Bland, Carroll, Grayson, Pulaski, Smyth, Tazewell and 2 more	110 min
Oct 23, 5:06 PM EDT	Flash Flood Warning	RNK	Bland, Carroll, Grayson, Smyth, Tazewell, Wythe and 1 more	6 hr
Oct 23, 5:26 PM EDT	Tornado Warning	RNK	Carroll, Grayson	34 min
Oct 23, 5:47 PM EDT	Severe Thunderstorm Warning	RNK	Carroll, Patrick	58 min
Oct 23, 5:53 PM EDT	Flash Flood Warning	RNK	Carroll, Floyd, Patrick	6 hr
Oct 23, 5:55 PM EDT	Tornado Warning	RNK	Carroll, Grayson, City of Galax	35 min
Oct 23, 6:16 PM EDT	Special Weather Statement	RNK	Alleghany, Craig, Giles, Montgomery, Pulaski, City of Covington and 1 more	89 min
Oct 23, 6:16 PM EDT	Severe Thunderstorm Warning	RNK	Bland, Carroll, Floyd, Giles, Montgomery, Pulaski and 2 more	59 min
Oct 23, 6:24 PM EDT	Special Weather Statement	RNK	Bath, Botetourt, Roanoke, Rockbridge, City of Buena Vista, City of Lexington and 2 more	111 min
Oct 23, 6:42 PM EDT	Severe Thunderstorm Warning	RNK	Craig, Giles, Montgomery, Pulaski	63 min
Oct 23, 6:46 PM EDT	Severe Thunderstorm Warning	RNK	Floyd, Franklin, Henry, Patrick, Pittsylvania, City of Martinsville	59 min
Oct 23, 6:58 PM EDT	Flash Flood Warning	RNK	Alleghany, Craig, Floyd, Giles, Montgomery, City of Covington	6 hr
Oct 23, 7:16 PM EDT	Tornado Warning	RNK	Franklin, Henry, Pittsylvania, City of Danville, City of Martinsville	29 min
Oct 23, 7:28 PM EDT	Severe Thunderstorm Warning	RNK	Alleghany, Bath, Botetourt, Craig, Roanoke, Rockbridge and 3 more	62 min
Oct 23, 7:40 PM EDT	Severe Thunderstorm Warning	RNK	Amherst, Bedford, Botetourt, Campbell, Franklin, Roanoke and 5 more	65 min
Oct 23, 7:50 PM EDT	Special Weather Statement	RNK	Campbell, Pittsylvania, City of Danville, City of Lynchburg	55 min
Oct 23, 2:46 PM EDT	Flash Flood Warning	RNK	Alleghany, Ashe, Watauga	6 hr
Oct 23, 5:00 PM EDT	Tornado Warning	RNK	Ashe, Wilkes	30 min
Oct 23, 5:23 PM EDT	Severe Thunderstorm Warning	RNK	Surry, Wilkes, Yadkin	67 min

Nearby

Flash Flood Watches in Virginia, 2017 Flash Flood Watches in North Carolina, 2017 Every flash flood watch in 2017

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.