Alert archive / Maryland / Mesoscale Discussions in 2011

Mesoscale Discussion 144

February 25, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Feb 25, 2011, 2:40 PM EST for 4 states. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued: Feb 25, 2011, 2:40 PM EST (19:40 UTC)
Expired: Feb 25, 2011, 3:45 PM EST
In force: 65 min
Issued by: the Storm Prediction Center

All 30 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Dorchester County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Wicomico County, MD, Atlantic County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Arlington County, VA, City of Alexandria, VA, City of Falls Church, VA, City of Fredericksburg, VA, King George County, VA, Stafford County, VA

The radar

The Dover AFB radar (KDOX), 69 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.7 hours before the alert went out and 101 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: 482 m above ground
0-6 km bulk shear: 68 kt
0-1 km storm-relative helicity: 557 m²/s²
0-3 km storm-relative helicity: 622 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
Feb 25, 11:36 AM EST	Mesoscale Discussion	SPC	Kent, New Castle, Sussex	84 min
Feb 25, 12:19 PM EST	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	3 hr
Feb 24, 11:59 PM EST	Severe Thunderstorm Watch	SPC	Lee	5 hr
Feb 25, 1:48 AM EST	Mesoscale Discussion	SPC	Alleghany, Bland, Buchanan, Carroll, Craig, Dickenson and 16 more	27 min

Nearby

Mesoscale Discussions in Maryland, 2011 Mesoscale Discussions in New Jersey, 2011 Mesoscale Discussions in Virginia, 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.