Alert archive / Virginia / Flash Flood Watches in 2018

Flash Flood Watch 3, NWS Blacksburg, VA

May 28, 201833 counties in Virginia; 9 counties in North Carolina; Mercer County, West Virginia

NWS Blacksburg, VA issued this flash flood watch at May 28, 2018, 3:13 PM EDT for 33 counties in Virginia; 9 counties in North Carolina; Mercer County, West Virginia. It took effect at May 29, 2018, 8:00 AM EDT. It was in force for 64 hr.

The area

The counties it named.

The facts

Issued
May 28, 2018, 3:13 PM EDT (19:13 UTC)
In effect from
May 29, 2018, 8:00 AM EDT
Expired
Jun 1, 2018, 12:00 AM EDT
In force
64 hr
Issued by
NWS Blacksburg, VA
Flood severity
None
All 43 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, Amherst County, VA, Appomattox 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 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, 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

The radar

The Roanoke radar (KFCX), 12 km from the middle of the area, began a volume at 19:13 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, 7.2 hours before the alert went out and 64 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-pSkew-T log-p diagram, Roanoke, VA at 12:00Z on 2018-05-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Roanoke, VA at 12:00Z on 2018-05-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
991 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
-10 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 May 28, 1:41 PM EDT, 1 hour 32 minutes earlier.

Area forecast discussion, May 28, 1:41 PM EDT, 1 hour 32 minutes before
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Hazardous weather outlook, May 28, 4:48 AM EDT, 10 hours 25 minutes before
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In the hours before

Special weather statement, May 28, 1:11 PM EDT, 2 hours 2 minutes before
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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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The office that day

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

IssuedProductOfficeCountiesLasted
May 27, 8:52 PM EDTSpecial Weather StatementRNKAmherst, Appomattox, Bedford, Bland, Buckingham, Campbell and 8 more53 min
May 27, 9:15 PM EDTFlash Flood WarningRNKAmherst, Appomattox, Bedford, Campbell, City of Lynchburg3 hr
May 27, 9:52 PM EDTAreal Flood WarningRNKRoanoke, City of Roanoke, City of Salem6 hr
May 28, 12:23 AM EDTAreal Flood WarningRNKAmherst, Appomattox, Bedford, Campbell, City of Lynchburg3 hr
May 28, 1:11 PM EDTSpecial Weather StatementRNKBedford34 min
May 27, 8:27 PM EDTSpecial Weather StatementRNKAlleghany, Ashe, Watauga63 min
May 27, 10:33 PM EDTAreal Flood WarningRNKMercer3 hr

Nearby

Flash Flood Watches in Virginia, 2018Flash Flood Watches in North Carolina, 2018Flash Flood Watches in West Virginia, 2018Every 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.