Alert archive / Virginia / Flash Flood Watches in 2009

Flash Flood Watch 6, NWS Blacksburg, VA

June 16, 200929 counties in Virginia; Alleghany County, Ashe County, Watauga County, North Carolina; Mercer County, Monroe County, Summers County, West Virginia

NWS Blacksburg, VA issued this flash flood watch at Jun 16, 2009, 2:58 PM EDT for 29 counties in Virginia; Alleghany County, Ashe County, Watauga County, North Carolina; Mercer County, Monroe County, Summers County, West Virginia. It took effect at Jun 16, 2009, 6:00 PM EDT. It was in force for 26 hr.

The area

The counties it named.

The facts

Issued: Jun 16, 2009, 2:58 PM EDT (18:58 UTC)
In effect from: Jun 16, 2009, 6:00 PM EDT
Expired: Jun 17, 2009, 8:26 PM EDT
In force: 26 hr
Issued by: NWS Blacksburg, VA
Flood severity: None

All 35 counties

Alleghany County, NC, Ashe County, NC, Watauga County, NC, Alleghany County, VA, Amherst 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 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, Henry 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, Mercer County, WV, Monroe County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 21 km from the middle of the area, began a volume at 19:01 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, 7.0 hours before the alert went out and 130 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: 134 J/kg
Mixed-layer CIN: -20 J/kg
Mixed-layer LCL: 451 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 30 m²/s²
0-3 km storm-relative helicity: 64 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

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 16, 2:44 PM EDT, 14 minutes earlier.

Area forecast discussion, Jun 16, 2:44 PM EDT, 14 minutes before

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Hazardous weather outlook, Jun 16, 8:59 AM EDT, 5 hours 59 minutes before

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In the hours before

Local storm report, Jun 16, 9:06 AM EDT, 5 hours 52 minutes before

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Local storm report, Jun 16, 9:59 AM EDT, 4 hours 59 minutes before

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Local storm report, Jun 16, 10:05 AM EDT, 4 hours 53 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 15, 11:01 PM EDT	Special Weather Statement	RNK	Tazewell	59 min
Jun 15, 11:44 PM EDT	Flash Flood Watch	RNK	Bland, Carroll, Floyd, Giles, Grayson, Henry and 9 more	9 hr
Jun 16, 12:42 AM EDT	Flash Flood Warning	RNK	Tazewell	5 hr
Jun 16, 4:31 AM EDT	Flash Flood Warning	RNK	Carroll, Floyd, Franklin, Patrick	6 hr
Jun 16, 6:27 AM EDT	Flash Flood Warning	RNK	Henry, City of Martinsville	6 hr
Jun 16, 9:59 AM EDT	Areal Flood Warning	RNK	Wythe	6 hr
Jun 16, 7:54 PM EDT	Severe Thunderstorm Warning	RNK	Grayson, Smyth	81 min
Jun 16, 7:44 PM EDT	Flash Flood Warning	RNK	Ashe, Wilkes	6 hr

Nearby

Flash Flood Watches in Virginia, 2009 Flash Flood Watches in North Carolina, 2009 Flash Flood Watches in West Virginia, 2009 Every flash flood watch in 2009

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.