Alert archive / Alabama / Mesoscale Discussions in 2009
Mesoscale Discussion 532
The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2009, 8:19 PM CDT for 24 counties in Alabama. It was in force for 56 min.
The area
The outline as issued.
The facts
- Issued
- Apr 19, 2009, 8:19 PM CDT (01:19 UTC)
- Expired
- Apr 19, 2009, 9:15 PM CDT
- In force
- 56 min
- Issued by
- the Storm Prediction Center
All 24 counties
Autauga County, AL, Bibb County, AL, Bullock County, AL, Calhoun County, AL, Chambers County, AL, Cherokee County, AL, Chilton County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Dallas County, AL, Elmore County, AL, Etowah County, AL, Jefferson County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Montgomery County, AL, Perry County, AL, Randolph County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tallapoosa County, AL
The radar
The Birmingham radar (KBMX), 56 km from the middle of the area, began a volume at 01:21 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
Birmingham, AL (KBMX), launched 00:00Z, 1.3 hours before the alert went out and 57 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.
- Mixed-layer CAPE
- 225 J/kg
- Mixed-layer CIN
- 0 J/kg
- Mixed-layer LCL
- 490 m above ground
- 0-6 km bulk shear
- 52 kt
- 0-1 km storm-relative helicity
- 466 m²/s²
- 0-3 km storm-relative helicity
- 529 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 2.5
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.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 19, 7:27 PM CDT | Mesoscale Discussion | SPC | Blount, Cullman, DeKalb, Madison, Marshall, Morgan and 1 more | 63 min |
| Apr 19, 8:45 PM CDT | Tornado Watch | SPC | Autauga, Barbour, Bibb, Bullock, Calhoun, Chambers and 22 more | 4 hr |
| Apr 19, 10:21 PM CDT | Mesoscale Discussion | SPC | Autauga, Bullock, Calhoun, Chambers, Cherokee, Chilton and 12 more | 84 min |
| Apr 20, 12:22 AM CDT | Mesoscale Discussion | SPC | Bullock, Butler, Chambers, Crenshaw, Elmore, Lee and 6 more | 53 min |
Nearby
Mesoscale Discussions in Alabama, 2009Every mesoscale discussion in 2009
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.