Alert archive / Arkansas / Mesoscale Discussions in 2019

Mesoscale Discussion 722

May 21, 201932 counties in Arkansas; 16 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 21, 2019, 9:57 AM CDT for 32 counties in Arkansas; 16 counties in Missouri. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
May 21, 2019, 9:57 AM CDT (14:57 UTC)
Expired
May 21, 2019, 11:30 AM CDT
In force
93 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 48 counties

Baxter County, AR, Boone County, AR, Carroll County, AR, Clark County, AR, Cleburne County, AR, Conway County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Garland County, AR, Hot Spring County, AR, Howard County, AR, Izard County, AR, Johnson County, AR, Little River County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Montgomery County, AR, Newton County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Pope County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sevier County, AR, Stone County, AR, Van Buren County, AR, Yell County, AR, Camden County, MO, Christian County, MO, Dallas County, MO, Douglas County, MO, Greene County, MO, Hickory County, MO, Howell County, MO, Laclede County, MO, Ozark County, MO, Polk County, MO, Pulaski County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Webster County, MO, Wright County, MO

The radar

The Western Arkansas radar (KSRX), 139 km from the middle of the area, began a volume at 14:56 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 3.0 hours before the alert went out and 127 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-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2019-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 12:00Z on 2019-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
1076 m above ground
0-6 km bulk shear
72 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
401 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

As transmitted.

<!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.

IssuedProductOfficeCountiesLasted
May 20, 10:30 PM CDTMesoscale DiscussionSPCBenton, Boone, Carroll, Crawford, Franklin, Madison and 4 more60 min
May 20, 11:06 PM CDTMesoscale DiscussionSPCBenton24 min
May 21, 12:18 AM CDTTornado WatchSPCBaxter, Benton, Boone, Carroll, Crawford, Franklin and 6 more5 hr
May 21, 12:55 AM CDTMesoscale DiscussionSPCClay, Fulton, Randolph95 min
May 21, 5:09 AM CDTTornado WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more9 hr
May 21, 7:26 AM CDTMesoscale DiscussionSPCBenton, Crawford, Little River, Polk, Scott, Sebastian and 2 more94 min
May 21, 11:32 AM CDTTornado WatchSPCBaxter, Boone, Cleburne, Conway, Faulkner, Fulton and 19 more7 hr
May 21, 1:51 PM CDTMesoscale DiscussionSPCBaxter, Boone, Marion, Newton, Pope, Searcy84 min
May 21, 4:43 PM CDTMesoscale DiscussionSPCClay, Craighead, Cross, Greene, Jackson, Lawrence and 3 more62 min
May 20, 8:20 PM CDTSevere Thunderstorm WatchSPCBenton, Camden, Dent, Hickory, Howell, Laclede and 10 more8 hr
May 21, 3:10 PM CDTTornado WatchSPCAudrain, Bollinger, Boone, Butler, Callaway, Cape Girardeau and 32 more8 hr
May 21, 5:43 PM CDTMesoscale DiscussionSPCBollinger, Butler, Cape Girardeau, Carter, Crawford, Franklin and 20 more62 min
May 21, 6:12 PM CDTMesoscale DiscussionSPCSaint Charles, Saint Louis, City of Saint Louis33 min
May 21, 6:53 PM CDTSevere Thunderstorm WatchSPCAtchison, Holt3 hr

Nearby

Mesoscale Discussions in Arkansas, 2019Mesoscale Discussions in Missouri, 2019Every mesoscale discussion in 2019

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.