Alert archive / Arkansas / Mesoscale Discussions in 2017

Mesoscale Discussion 230

February 28, 201726 counties in Arkansas; 17 counties in Oklahoma; Fannin County, Lamar County, Red River County, Texas

The Storm Prediction Center issued this mesoscale discussion at Feb 28, 2017, 10:46 PM CST for 26 counties in Arkansas; 17 counties in Oklahoma; Fannin County, Lamar County, Red River County, Texas. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued
Feb 28, 2017, 10:46 PM CST (04:46 UTC)
Expired
Mar 1, 2017, 12:45 AM CST
In force
119 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 46 counties

Boone County, AR, Carroll County, AR, Conway County, AR, Crawford County, AR, Franklin County, AR, Garland County, AR, Hempstead County, AR, Howard 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, Scott County, AR, Searcy County, AR, Sebastian County, AR, Sevier County, AR, Van Buren County, AR, Washington County, AR, Yell County, AR, Adair County, OK, Atoka County, OK, Bryan County, OK, Choctaw County, OK, Coal County, OK, Haskell County, OK, Hughes County, OK, Johnston County, OK, Latimer County, OK, LeFlore County, OK, Marshall County, OK, McCurtain County, OK, McIntosh County, OK, Muskogee County, OK, Pittsburg County, OK, Pushmataha County, OK, Sequoyah County, OK, Fannin County, TX, Lamar County, TX, Red River County, TX

The radar

The Western Arkansas radar (KSRX), 65 km from the middle of the area, began a volume at 04:48 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 00:00Z, 4.8 hours before the alert went out and 251 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 00:00Z on 2017-03-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1117 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2017-03-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 341 square meters per square second.1939587897117136Sfc1 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
1117 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
341 m²/s²
0-3 km storm-relative helicity
315 m²/s²
Significant tornado parameter
2.3
Supercell composite
8.2

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
Feb 28, 7:46 PM CSTMesoscale DiscussionSPCBaxter, Clay, Cleburne, Craighead, Cross, Fulton and 14 more119 min
Feb 28, 8:29 PM CSTTornado WatchSPCClay, Craighead, Greene, Lawrence, Mississippi, Poinsett and 1 more12 hr
Feb 28, 9:04 PM CSTTornado WatchSPCBenton, Carroll, Madison, Washington7 hr
Feb 28, 11:35 PM CSTTornado WatchSPCBaxter, Boone, Cleburne, Conway, Crawford, Faulkner and 24 more5 hr
Mar 1, 2:09 AM CSTMesoscale DiscussionSPCArkansas, Clark, Clay, Cleburne, Cleveland, Conway and 38 more2 hr
Mar 1, 3:03 AM CSTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 4 more5 hr
Mar 1, 4:19 AM CSTMesoscale DiscussionSPCCrittenden56 min
Feb 28, 10:01 PM CSTMesoscale DiscussionSPCCraig, Delaware, Mayes, Nowata, Osage, Ottawa and 4 more119 min

Nearby

Mesoscale Discussions in Arkansas, 2017Mesoscale Discussions in Oklahoma, 2017Mesoscale Discussions in Texas, 2017Every mesoscale discussion in 2017

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.