Alert archive / Mississippi / Heat Advisories in 2011

Heat Advisory 9, NWS Memphis, TN

August 18, 201122 counties in Mississippi; 16 counties in Tennessee; 12 counties in Arkansas

NWS Memphis, TN issued this heat advisory at Aug 18, 2011, 2:38 AM CDT for 22 counties in Mississippi; 16 counties in Tennessee; 12 counties in Arkansas. It took effect at Aug 19, 2011, 12:00 PM CDT. It was in force for .

The area

The counties it named.

The facts

Issued: Aug 18, 2011, 2:38 AM CDT (07:38 UTC)
In effect from: Aug 19, 2011, 12:00 PM CDT
Expired: Aug 18, 2011, 3:14 PM CDT
In force
Issued by: NWS Memphis, TN

All 50 counties

Clay County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Greene County, AR, Lawrence County, AR, Lee County, AR, Mississippi County, AR, Phillips County, AR, Poinsett County, AR, Randolph County, AR, St. Francis County, AR, Alcorn County, MS, Benton County, MS, Calhoun County, MS, Chickasaw County, MS, Coahoma County, MS, DeSoto County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Marshall County, MS, Monroe County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Yalobusha County, MS, Carroll County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Lauderdale County, TN, Madison County, TN, McNairy County, TN, Shelby County, TN, Tipton County, TN

The radar

The Memphis radar (KNQA), 45 km from the middle of the area, began a volume at 07:43 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

Little Rock, AR (KLZK), launched 00:00Z, 7.6 hours before the alert went out and 45 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: 3873 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 1422 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 87 m²/s²
0-3 km storm-relative helicity: 135 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this heat advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Memphis, TN wrote its last area forecast discussion before this heat advisory went out at Aug 17, 11:49 PM CDT, 2 hours 49 minutes earlier.

Area forecast discussion, Aug 17, 11:49 PM CDT, 2 hours 49 minutes before

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Hazardous weather outlook, Aug 17, 3:39 AM CDT, 22 hours 59 minutes before

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  <meta name="viewport" content="width=device-width, initial-scale=1">
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  <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.
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The office that day

Everything else NWS Memphis, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 18, 7:28 AM CDT	Severe Thunderstorm Warning	MEG	DeSoto	47 min
Aug 18, 6:13 AM CDT	Severe Thunderstorm Warning	MEG	Tipton	47 min
Aug 18, 6:53 AM CDT	Special Weather Statement	MEG	Shelby	37 min
Aug 18, 6:07 AM CDT	Special Weather Statement	MEG	Crittenden	38 min
Aug 18, 6:23 AM CDT	Special Weather Statement	MEG	Poinsett	52 min
Aug 18, 7:51 AM CDT	Special Weather Statement	MEG	Lee, Phillips, St. Francis	39 min

Nearby

Heat Advisories in Mississippi, 2011 Heat Advisories in Tennessee, 2011 Heat Advisories in Arkansas, 2011 Every heat advisory 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.