Alert archive / Michigan / Severe Thunderstorm Watches in 2001

Severe Thunderstorm Watch 730

September 8, 200113 counties in Michigan

The Storm Prediction Center issued this severe thunderstorm watch at Sep 8, 2001, 4:30 PM EDT for 13 counties in Michigan. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Sep 8, 2001, 4:30 PM EDT (20:30 UTC)
Expired
Sep 8, 2001, 10:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center

Counties Alcona County, MI, Alpena County, MI, Arenac County, MI, Cheboygan County, MI, Clare County, MI, Crawford County, MI, Iosco County, MI, Montmorency County, MI, Ogemaw County, MI, Oscoda County, MI, Otsego County, MI, Presque Isle County, MI, Roscommon County, MI

Warnings issued inside it

2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Sep 8, 5:39 PM EDTSevere Thunderstorm WarningAPXOgemaw36 min
Sep 8, 5:54 PM EDTSevere Thunderstorm WarningAPXIosco51 min

The nearest sounding before it

Alpena, MI (KAPX), launched 12:00Z, 8.5 hours before the alert went out and 142 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, Alpena, MI at 12:00Z on 2001-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 388 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, Alpena, MI at 12:00Z on 2001-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 141 square meters per square second.19395878Sfc1 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
388 J/kg
Mixed-layer CIN
-114 J/kg
Mixed-layer LCL
638 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
141 m²/s²
0-3 km storm-relative helicity
142 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
Sep 7, 8:45 PM EDTSevere Thunderstorm WatchSPCDelta, Dickinson, Menominee3 hr
Sep 8, 12:15 AM EDTSevere Thunderstorm WatchSPCAntrim, Benzie, Charlevoix, Cheboygan, Chippewa, Clare and 22 more5 hr
Sep 8, 2:30 PM EDTSevere Thunderstorm WatchSPCAllegan, Arenac, Barry, Bay, Branch, Calhoun and 28 more7 hr

Nearby

Severe Thunderstorm Watches in Michigan, 2001Every severe thunderstorm watch in 2001

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.