Alert archive / North Carolina / Mesoscale Discussions in 2009

Mesoscale Discussion 410

April 6, 200914 counties in North Carolina; 14 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Apr 6, 2009, 1:08 PM EDT for 14 counties in North Carolina; 14 counties in Virginia. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued: Apr 6, 2009, 1:08 PM EDT (17:08 UTC)
Expired: Apr 6, 2009, 2:15 PM EDT
In force: 67 min
Issued by: the Storm Prediction Center

All 28 counties

Beaufort County, NC, Camden County, NC, Carteret County, NC, Chowan County, NC, Craven County, NC, Currituck County, NC, Dare County, NC, Gates County, NC, Hyde County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Tyrrell County, NC, Washington County, NC, Accomack County, VA, City of Chesapeake, VA, City of Hampton, VA, City of Newport News, VA, City of Norfolk, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, Gloucester County, VA, Lancaster County, VA, Mathews County, VA, Northampton County, VA, York County, VA

The radar

The Morehead City radar (KMHX), 138 km from the middle of the area, began a volume at 17:11 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

Newport, NC (KMHX), launched 12:00Z, 5.1 hours before the alert went out and 138 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: 1894 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 462 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 337 m²/s²
0-3 km storm-relative helicity: 342 m²/s²
Significant tornado parameter: 4.4
Supercell composite: 17.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

<!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>

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 6, 3:37 AM EDT	Mesoscale Discussion	SPC	Anson, Bladen, Brunswick, Columbus, Cumberland, Duplin and 17 more	83 min
Apr 6, 7:07 AM EDT	Tornado Watch	SPC	Bladen, Brunswick, Columbus, New Hanover, Pender, Robeson	6 hr
Apr 6, 8:03 AM EDT	Tornado Watch	SPC	Beaufort, Bertie, Camden, Carteret, Chowan, Craven and 32 more	7 hr
Apr 6, 10:33 AM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 36 more	57 min
Apr 5, 8:12 PM EDT	Mesoscale Discussion	SPC	Buchanan, Dickenson, Lee, Scott, Wise, City of Norton	63 min
Apr 5, 8:53 PM EDT	Severe Thunderstorm Watch	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Washington and 3 more	5 hr
Apr 6, 12:08 AM EDT	Mesoscale Discussion	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Wise and 1 more	67 min

Nearby

Mesoscale Discussions in North Carolina, 2009 Mesoscale Discussions in Virginia, 2009 Every mesoscale discussion 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.