Alert archive / Arizona / Mesoscale Discussions in 2014

Mesoscale Discussion 1771

September 27, 20146 counties in Arizona; 5 counties in Utah

The Storm Prediction Center issued this mesoscale discussion at Sep 27, 2014, 1:40 PM MST for 6 counties in Arizona; 5 counties in Utah. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Sep 27, 2014, 1:40 PM MST (20:40 UTC)
Expired: Sep 27, 2014, 3:45 PM MST
In force: 2 hr
Issued by: the Storm Prediction Center

Counties Coconino County, AZ, Gila County, AZ, Maricopa County, AZ, Navajo County, AZ, Pinal County, AZ, Yavapai County, AZ, Garfield County, UT, Kane County, UT, Piute County, UT, San Juan County, UT, Wayne County, UT

The radar

The Flagstaff radar (KFSX), 71 km from the middle of the area, began a volume at 20:42 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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.7 hours before the alert went out and 41 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: 699 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 686 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 77 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.3

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.

Issued	Product	Office	Counties	Lasted
Sep 26, 9:34 PM MST	Mesoscale Discussion	SPC	Mohave	2 hr
Sep 27, 1:44 AM MST	Mesoscale Discussion	SPC	Mohave	2 hr
Sep 27, 3:16 AM MST	Severe Thunderstorm Watch	SPC	Coconino, Mohave, Yavapai	8 hr
Sep 27, 7:12 AM MST	Mesoscale Discussion	SPC	Coconino, Mohave, Yavapai	2 hr
Sep 27, 9:53 AM MST	Mesoscale Discussion	SPC	Coconino, Maricopa, Yavapai	67 min
Sep 27, 10:21 AM MST	Severe Thunderstorm Watch	SPC	Coconino, Gila, Maricopa, Navajo, Pinal, Yavapai	8 hr
Sep 27, 4:08 PM MST	Mesoscale Discussion	SPC	Gila, Graham, Navajo, Pinal	2 hr

Nearby

Mesoscale Discussions in Arizona, 2014 Mesoscale Discussions in Utah, 2014 Every mesoscale discussion in 2014

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.