Alert archive / Virginia / Flash Flood Watches in 2018

Flash Flood Watch 4, NWS Blacksburg, VA

June 2, 201828 counties in Virginia; Caswell County, Rockingham County, North Carolina; Greenbrier County, Monroe County, Summers County, West Virginia

NWS Blacksburg, VA issued this flash flood watch at Jun 2, 2018, 11:32 AM EDT for 28 counties in Virginia; Caswell County, Rockingham County, North Carolina; Greenbrier County, Monroe County, Summers County, West Virginia. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued: Jun 2, 2018, 11:32 AM EDT (15:32 UTC)
Expired: Jun 2, 2018, 8:30 PM EDT
In force: 9 hr
Issued by: NWS Blacksburg, VA
Flood severity: None

All 33 counties

Caswell County, NC, Rockingham County, NC, Alleghany County, VA, Amherst County, VA, Appomattox County, VA, Bath County, VA, Bedford County, VA, Botetourt County, VA, Buckingham County, VA, Campbell County, VA, Charlotte County, VA, City of Buena Vista, VA, City of Covington, VA, City of Danville, VA, City of Lexington, VA, City of Lynchburg, VA, City of Martinsville, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Floyd County, VA, Franklin County, VA, Giles County, VA, Halifax County, VA, Henry County, VA, Montgomery County, VA, Patrick County, VA, Pittsylvania County, VA, Roanoke County, VA, Rockbridge County, VA, Greenbrier County, WV, Monroe County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 55 km from the middle of the area, began a volume at 15:32 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, 3.5 hours before the alert went out and 22 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: 31 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 810 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -43 m²/s²
0-3 km storm-relative helicity: -69 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 Jun 2, 9:58 AM EDT, 1 hour 34 minutes earlier.

Area forecast discussion, Jun 2, 9:58 AM EDT, 1 hour 34 minutes before

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Hazardous weather outlook, Jun 2, 4:46 AM EDT, 6 hours 46 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
Jun 1, 8:01 PM EDT	Special Weather Statement	RNK	Halifax	44 min
Jun 1, 8:30 PM EDT	Special Weather Statement	RNK	Charlotte	30 min
Jun 2, 4:49 AM EDT	Special Weather Statement	RNK	Craig, Giles	56 min
Jun 2, 12:41 PM EDT	Areal Flood Advisory	RNK	Amherst, Appomattox, Buckingham	3 hr
Jun 2, 1:04 PM EDT	Flash Flood Warning	RNK	Buckingham	5 hr
Jun 2, 3:42 PM EDT	Areal Flood Advisory	RNK	Amherst, Appomattox, Buckingham	2 hr

Nearby

Flash Flood Watches in Virginia, 2018 Flash Flood Watches in West Virginia, 2018 Flash Flood Watches in North Carolina, 2018 Every flash flood watch in 2018

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.