Alert archive / Maryland / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 36, NWS Baltimore/Washington

May 13, 2018Fairfax County, Virginia; Charles County, Prince George's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at May 13, 2018, 10:12 PM EDT for Fairfax County, Virginia; Charles County, Prince George's County, Maryland. It was in force for 48 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 13, 2018, 10:12 PM EDT (02:12 UTC)
Expired: May 13, 2018, 11:00 PM EDT
In force: 48 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Charles County, MD, Prince George's County, MD, Fairfax County, VA

The radar

The Sterling radar (KLWX), 48 km from the middle of the area, began a volume at 02:14 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 00:00Z, 2.2 hours before the alert went out and 40 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: 669 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 235 m²/s²
0-3 km storm-relative helicity: 389 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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 13, 9:37 PM EDT, 35 minutes earlier.

Area forecast discussion, May 13, 9:37 PM EDT, 35 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 13, 9:11 PM EDT, 1 hour 1 minute 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 13, 8:38 PM EDT, 1 hour 34 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>

Local storm report, May 13, 8:40 PM EDT, 1 hour 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>

Local storm report, May 13, 8:53 PM EDT, 1 hour 19 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>

Local storm report, May 13, 9:13 PM EDT, 59 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>

Local storm report, May 13, 9:14 PM EDT, 58 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>

Local storm report, May 13, 9:27 PM EDT, 45 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.

Issued	Product	Office	Counties	Lasted
May 13, 10:07 PM EDT	Special Marine Warning	LWX		38 min
May 13, 10:21 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, City of Alexandria	39 min
May 13, 10:25 PM EDT	Special Marine Warning	LWX		47 min
May 13, 10:50 PM EDT	Special Marine Warning	LWX		97 min
May 13, 11:36 PM EDT	Special Marine Warning	LWX		54 min
May 14, 5:32 AM EDT	Dense Fog Advisory	LWX	Clarke, Culpeper, Fauquier, Frederick, Greene, Loudoun and 8 more	4 hr
May 14, 6:24 AM EDT	Coastal Flood Advisory	LWX	Arlington, City of Alexandria, City of Falls Church	4 hr
May 14, 2:08 PM EDT	Small Craft Advisory	LWX		12 hr
May 14, 2:08 PM EDT	Small Craft Advisory	LWX		37 hr
May 14, 2:19 PM EDT	Severe Thunderstorm Warning	LWX	Augusta, City of Staunton, City of Waynesboro	41 min
May 14, 2:46 PM EDT	Severe Thunderstorm Warning	LWX	Greene, Madison, Orange	44 min
May 14, 2:55 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Nelson	50 min
May 14, 3:01 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Greene, Orange	44 min
May 14, 3:39 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Nelson	66 min
May 14, 3:46 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Greene, Orange	44 min
May 14, 3:54 PM EDT	Flash Flood Warning	LWX	Albemarle, Greene, Orange	5 hr
May 14, 4:15 PM EDT	Flash Flood Warning	LWX	Albemarle, Nelson	5 hr
May 14, 4:38 PM EDT	Severe Thunderstorm Warning	LWX	Madison, Page, Rappahannock, Warren	52 min
May 14, 4:51 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, Shenandoah, City of Winchester	39 min
May 14, 5:11 PM EDT	Severe Thunderstorm Warning	LWX	Nelson	49 min
May 14, 5:13 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, Page, Shenandoah, Warren, City of Winchester	47 min
May 14, 5:29 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Loudoun	61 min
May 14, 5:33 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Greene, Madison, Page, Rockingham, Shenandoah and 1 more	57 min
May 14, 5:35 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Culpeper, Fauquier, Loudoun, Madison, Page and 3 more	55 min
May 14, 5:42 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Augusta, Nelson, Rockingham, City of Staunton, City of Waynesboro	48 min
May 14, 5:49 PM EDT	Tornado Warning	LWX	Loudoun	26 min
May 14, 6:03 PM EDT	Special Marine Warning	LWX		117 min
May 14, 6:07 PM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, Fauquier, Loudoun, Prince William, City of Alexandria and 4 more	53 min
May 14, 6:11 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier, Greene, Madison, Orange, Prince William and 3 more	79 min
May 14, 6:12 PM EDT	Tornado Warning	LWX	Fairfax, Loudoun, City of Fairfax	33 min
May 14, 6:14 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Nelson, City of Charlottesville	76 min
May 14, 6:30 PM EDT	Special Marine Warning	LWX		2 hr
May 14, 6:31 PM EDT	Special Marine Warning	LWX		119 min
May 14, 6:33 PM EDT	Severe Thunderstorm Warning	LWX	King George	57 min
May 14, 6:56 PM EDT	Flash Flood Warning	LWX	Arlington, Fairfax, City of Alexandria, City of Falls Church	3 hr
May 14, 7:00 PM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, Prince William, City of Alexandria	30 min
May 14, 7:10 PM EDT	Special Marine Warning	LWX		95 min
May 14, 7:17 PM EDT	Flash Flood Warning	LWX	Page	2 hr
May 14, 7:29 PM EDT	Flash Flood Warning	LWX	Albemarle, Nelson	114 min
May 13, 9:17 PM EDT	Coastal Flood Advisory	LWX	Anne Arundel, Saint Mary's	9 hr
May 14, 4:12 PM EDT	Severe Thunderstorm Warning	LWX	Allegany	48 min
May 14, 4:19 PM EDT	Severe Thunderstorm Warning	LWX	Allegany, Washington	41 min
May 14, 7:12 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's	63 min
May 14, 7:45 PM EDT	Areal Flood Warning	LWX	Prince George's	2 hr
May 14, 4:39 PM EDT	Severe Thunderstorm Warning	LWX	Grant, Hardy, Pendleton	51 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2018 Severe Thunderstorm Warnings in Virginia, 2018 Every severe thunderstorm warning in 2018

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.