Alert archive / Virginia / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 25, NWS Baltimore/Washington

May 1, 20166 counties in Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at May 1, 2016, 8:12 PM EDT for 6 counties in Virginia. It was in force for 33 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 1, 2016, 8:12 PM EDT (00:12 UTC)
Expired
May 1, 2016, 8:45 PM EDT
In force
33 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Clarke County, VA, Fauquier County, VA, Frederick County, VA, Rappahannock County, VA, Shenandoah County, VA, Warren County, VA

The radar

The Sterling radar (KLWX), 59 km from the middle of the area, began a volume at 00:15 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 00:00Z, 0.2 hours before the alert went out and 224 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 00:00Z on 2016-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 911 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2016-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 125 square meters per square second.1939587897117Sfc1 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
911 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1315 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
125 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.4
Supercell composite
4.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Baltimore/Washington wrote its last area forecast discussion before this severe thunderstorm warning went out at May 1, 3:15 PM EDT, 4 hours 57 minutes earlier.

Area forecast discussion, May 1, 3:15 PM EDT, 4 hours 57 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<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>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Hazardous weather outlook, May 1, 1:40 PM EDT, 6 hours 32 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<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>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

In the hours before

Local storm report, May 1, 7:30 PM EDT, 42 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<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>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 1, 8:24 PM EDTSevere Thunderstorm WarningLWXPage, Rockingham, City of Harrisonburg16 min
May 1, 9:07 PM EDTSevere Thunderstorm WarningLWXPage, Rockingham, Shenandoah, Warren38 min
May 2, 5:42 AM EDTDense Fog AdvisoryLWXAlbemarle, Amherst, Arlington, Augusta, Clarke, Culpeper and 23 more2 hr
May 2, 4:50 PM EDTSevere Thunderstorm WarningLWXNelson40 min
May 2, 5:28 PM EDTSevere Thunderstorm WarningLWXAlbemarle, Nelson12 min
May 2, 5:45 PM EDTSpecial Marine WarningLWX90 min
May 2, 5:50 PM EDTSevere Thunderstorm WarningLWXFairfax, Prince William, City of Manassas, City of Manassas Park40 min
May 2, 6:15 PM EDTSevere Thunderstorm WarningLWXArlington, Fairfax, Prince William, City of Fairfax, City of Falls Church29 min
May 2, 6:27 PM EDTSevere Thunderstorm WarningLWXFairfax, Prince William, City of Alexandria48 min
May 2, 6:36 PM EDTSpecial Marine WarningLWX84 min
May 2, 7:00 PM EDTSpecial Marine WarningLWX2 hr
May 2, 7:24 PM EDTSevere Thunderstorm WarningLWXArlington, Fairfax, City of Fairfax, City of Falls Church28 min
May 2, 7:39 PM EDTSpecial Marine WarningLWX96 min
May 2, 7:59 PM EDTSpecial Marine WarningLWX91 min
May 2, 6:43 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's47 min
May 2, 6:57 PM EDTTornado WarningLWXCharles33 min
May 2, 7:18 PM EDTSevere Thunderstorm WarningLWXHoward, Montgomery30 min
May 2, 7:25 PM EDTSevere Thunderstorm WarningLWXCalvert, Charles, Prince George's, Saint Mary's35 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2016Every severe thunderstorm warning in 2016

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.