Alert archive / North Carolina / Mesoscale Discussions in 2008

Mesoscale Discussion 647

April 12, 20084 states

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2008, 3:39 PM EDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 12, 2008, 3:39 PM EDT (19:39 UTC)
Expired: Apr 12, 2008, 5:45 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 56 counties

Somerset County, MD, Worcester County, MD, Beaufort County, NC, Bertie County, NC, Bladen County, NC, Brunswick County, NC, Camden County, NC, Chowan County, NC, Columbus County, NC, Craven County, NC, Cumberland County, NC, Currituck County, NC, Duplin County, NC, Edgecombe County, NC, Gates County, NC, Greene County, NC, Hertford County, NC, Hyde County, NC, Johnston County, NC, Jones County, NC, Lenoir County, NC, Martin County, NC, New Hanover County, NC, Northampton County, NC, Onslow County, NC, Pamlico County, NC, Pasquotank County, NC, Pender County, NC, Perquimans County, NC, Pitt County, NC, Robeson County, NC, Sampson County, NC, Tyrrell County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Dillon County, SC, Florence County, SC, Horry County, SC, Marion County, SC, Accomack County, VA, City of Chesapeake, VA, City of Franklin, 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, Isle of Wight County, VA, Mathews County, VA, Northampton County, VA, Southampton County, VA, York County, VA

The radar

The Morehead City radar (KMHX), 97 km from the middle of the area, began a volume at 19:42 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, 7.7 hours before the alert went out and 96 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 915 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 191 m²/s²
0-3 km storm-relative helicity: 164 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 12, 11:59 AM EDT	Severe Thunderstorm Watch	SPC	Calvert, Dorchester, Saint Mary's, Somerset, Wicomico, Worcester	6 hr
Apr 12, 12:22 PM EDT	Mesoscale Discussion	SPC	Anne Arundel, Caroline, Kent, Queen Anne's, Talbot	83 min
Apr 12, 9:48 AM EDT	Mesoscale Discussion	SPC	Alamance, Anson, Cabarrus, Caswell, Catawba, Chatham and 36 more	117 min
Apr 12, 1:48 PM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Bladen, Camden, Chowan, Columbus and 29 more	57 min
Apr 12, 2:12 PM EDT	Severe Thunderstorm Watch	SPC	Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 38 more	4 hr

Nearby

Mesoscale Discussions in North Carolina, 2008 Mesoscale Discussions in Virginia, 2008 Mesoscale Discussions in South Carolina, 2008 Every mesoscale discussion in 2008

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.