Alert archive / North Carolina / Mesoscale Discussions in 2011

Mesoscale Discussion 454

April 16, 201131 counties in North Carolina; Horry County, South Carolina

The Storm Prediction Center issued this mesoscale discussion at Apr 16, 2011, 12:16 PM EDT for 31 counties in North Carolina; Horry County, South Carolina. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued: Apr 16, 2011, 12:16 PM EDT (16:16 UTC)
Expired: Apr 16, 2011, 1:15 PM EDT
In force: 59 min
Issued by: the Storm Prediction Center

All 32 counties

Beaufort County, NC, Bertie County, NC, Bladen County, NC, Brunswick County, NC, Chowan County, NC, Columbus County, NC, Craven County, NC, Cumberland County, NC, Duplin County, NC, Edgecombe County, NC, Franklin County, NC, Greene County, NC, Halifax County, NC, Harnett County, NC, Hertford County, NC, Johnston County, NC, Jones County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, New Hanover County, NC, Northampton County, NC, Onslow County, NC, Pender County, NC, Pitt County, NC, Sampson County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wayne County, NC, Wilson County, NC, Horry County, SC

The radar

The Raleigh/Durham radar (KRAX), 71 km from the middle of the area, began a volume at 16:17 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, 4.3 hours before the alert went out and 110 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: 7 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 824 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 201 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 16, 5:57 AM EDT	Tornado Watch	SPC	Alexander, Cabarrus, Catawba, Cleveland, Davie, Gaston and 9 more	8 hr
Apr 16, 10:39 AM EDT	Mesoscale Discussion	SPC	Alamance, Anson, Bertie, Bladen, Brunswick, Cabarrus and 52 more	2 hr
Apr 16, 12:02 PM EDT	Tornado Watch PDS	SPC	Alamance, Anson, Beaufort, Bertie, Bladen, Brunswick and 60 more	11 hr
Apr 16, 2:28 PM EDT	Mesoscale Discussion	SPC	Alamance, Beaufort, Bertie, Bladen, Brunswick, Camden and 49 more	92 min
Apr 16, 4:49 PM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 34 more	86 min
Apr 16, 6:59 PM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 28 more	91 min
Apr 16, 5:09 AM EDT	Mesoscale Discussion	SPC	Abbeville, Aiken, Anderson, Chester, Edgefield, Fairfield and 10 more	96 min

Nearby

Mesoscale Discussions in North Carolina, 2011 Mesoscale Discussions in South Carolina, 2011 Every mesoscale discussion in 2011

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.