Alert archive / Montana / Mesoscale Discussions in 2015

Mesoscale Discussion 846

May 30, 20154 counties in Idaho; 40 counties in Montana

The Storm Prediction Center issued this mesoscale discussion at May 30, 2015, 1:00 PM PDT for 4 counties in Idaho; 40 counties in Montana. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 30, 2015, 1:00 PM PDT (20:00 UTC)
Expired: May 30, 2015, 3:00 PM PDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 44 counties

Bonner County, ID, Boundary County, ID, Kootenai County, ID, Shoshone County, ID, Big Horn County, MT, Blaine County, MT, Broadwater County, MT, Carbon County, MT, Cascade County, MT, Chouteau County, MT, Deer Lodge County, MT, Fergus County, MT, Flathead County, MT, Gallatin County, MT, Garfield County, MT, Glacier County, MT, Golden Valley County, MT, Granite County, MT, Hill County, MT, Jefferson County, MT, Judith Basin County, MT, Lake County, MT, Lewis and Clark County, MT, Liberty County, MT, Lincoln County, MT, Meagher County, MT, Mineral County, MT, Missoula County, MT, Musselshell County, MT, Park County, MT, Petroleum County, MT, Phillips County, MT, Pondera County, MT, Powell County, MT, Rosebud County, MT, Sanders County, MT, Silver Bow County, MT, Stillwater County, MT, Sweet Grass County, MT, Teton County, MT, Toole County, MT, Treasure County, MT, Wheatland County, MT, Yellowstone County, MT

The radar

The Great Falls radar (KTFX), 48 km from the middle of the area, began a volume at 20:01 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

Spokane, WA (KOTX), launched 12:00Z, 8.0 hours before the alert went out and 340 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1654 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 130 m²/s²
0-3 km storm-relative helicity: 191 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>

Nearby

Mesoscale Discussions in Montana, 2015 Mesoscale Discussions in Idaho, 2015 Every 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.