Alert archive / Alabama / Mesoscale Discussions in 2015

Mesoscale Discussion 374

April 19, 201523 counties in Alabama; 8 counties in Florida; 17 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2015, 5:51 AM CDT for 23 counties in Alabama; 8 counties in Florida; 17 counties in Georgia. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued
Apr 19, 2015, 5:51 AM CDT (10:51 UTC)
Expired
Apr 19, 2015, 7:45 AM CDT
In force
114 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 48 counties

Autauga County, AL, Baldwin County, AL, Barbour County, AL, Bullock County, AL, Butler County, AL, Coffee County, AL, Conecuh County, AL, Coosa County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Elmore County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Montgomery County, AL, Pike County, AL, Russell County, AL, Tallapoosa County, AL, Calhoun County, FL, Escambia County, FL, Holmes County, FL, Jackson County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL, Baker County, GA, Calhoun County, GA, Chattahoochee County, GA, Clay County, GA, Decatur County, GA, Early County, GA, Marion County, GA, Miller County, GA, Muscogee County, GA, Quitman County, GA, Randolph County, GA, Schley County, GA, Seminole County, GA, Stewart County, GA, Sumter County, GA, Terrell County, GA, Webster County, GA

The radar

The Ft Rucker radar (KEOX), 46 km from the middle of the area, began a volume at 10:54 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

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 10.9 hours before the alert went out and 172 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, Tallahassee Rgnl, FL at 00:00Z on 2015-04-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 851 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, Tallahassee Rgnl, FL at 00:00Z on 2015-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 square meters per square second.193958Sfc1 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
851 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
888 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
132 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.

IssuedProductOfficeCountiesLasted
Apr 19, 2:06 AM CDTMesoscale DiscussionSPCChoctaw, Clarke, Marengo, Washington84 min
Apr 19, 6:57 AM CDTTornado WatchSPCBarbour, Bullock, Butler, Chambers, Clay, Coffee and 16 more7 hr
Apr 19, 1:14 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Calhoun, Chambers, Cherokee and 36 more2 hr
Apr 19, 5:25 PM CDTMesoscale DiscussionSPCCalhoun, Cherokee, Cleburne, DeKalb, Etowah95 min
Apr 19, 11:24 AM CDTMesoscale DiscussionSPCHamilton, Jefferson, Madison, Suwannee, Taylor2 hr
Apr 19, 12:04 PM CDTTornado WatchSPCBaker, Columbia, Dixie, Duval, Gilchrist, Hamilton and 5 more7 hr
Apr 19, 3:56 PM CDTMesoscale DiscussionSPCFlagler, Lake, Marion, Orange, Putnam, Saint Johns and 3 more94 min
Apr 19, 9:40 AM CDTMesoscale DiscussionSPCBleckley, Calhoun, Crisp, Dodge, Dooly, Dougherty and 11 more2 hr

Nearby

Mesoscale Discussions in Alabama, 2015Mesoscale Discussions in Georgia, 2015Mesoscale Discussions in Florida, 2015Every mesoscale discussion in 2015

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.