Alert archive / Arizona / Winter Weather Advisories in 2021

Winter Weather Advisory 2, NWS Phoenix, AZ

January 24, 2021Gila County, Maricopa County, Pinal County, Arizona

NWS Phoenix, AZ issued this winter weather advisory at Jan 24, 2021, 1:09 PM MST for Gila County, Maricopa County, Pinal County, Arizona. It took effect at Jan 25, 2021, 11:00 PM MST. It was in force for 18 hr.

The area

The counties it named.

The facts

Issued: Jan 24, 2021, 1:09 PM MST (20:09 UTC)
In effect from: Jan 25, 2021, 11:00 PM MST
Expired: Jan 26, 2021, 5:00 PM MST
In force: 18 hr
Issued by: NWS Phoenix, AZ

Counties Gila County, AZ, Maricopa County, AZ, Pinal County, AZ

The radar

The Phoenix radar (KIWA), 13 km from the middle of the area, began a volume at 20:11 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

Tuscon, AZ (KTUS), launched 12:00Z, 8.2 hours before the alert went out and 145 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: 29 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 1170 m above ground
0-6 km bulk shear: 98 kt
0-1 km storm-relative helicity: 122 m²/s²
0-3 km storm-relative helicity: 231 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this winter weather advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Phoenix, AZ wrote its last area forecast discussion before this winter weather advisory went out at Jan 24, 11:37 AM MST, 1 hour 32 minutes earlier.

Area forecast discussion, Jan 24, 11:37 AM MST, 1 hour 32 minutes before

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In the hours before

Local storm report, Jan 24, 10:06 AM MST, 3 hours 3 minutes before

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Special weather statement, Jan 24, 11:07 AM MST, 2 hours 2 minutes before

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<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.
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Special weather statement, Jan 24, 11:27 AM MST, 1 hour 42 minutes before

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<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>
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</body>
</html>

The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 24, 5:45 AM MST	Special Weather Statement	PSR		45 min
Jan 24, 11:07 AM MST	Special Weather Statement	PSR	Pinal	23 min
Jan 24, 11:27 AM MST	Special Weather Statement	PSR	Pinal	33 min
Jan 24, 1:09 PM MST	Winter Storm Warning	PSR	Gila, Maricopa, Pinal	52 hr
Jan 24, 1:22 PM MST	Special Weather Statement	PSR		23 min
Jan 24, 2:02 PM MST	Special Weather Statement	PSR	Maricopa	28 min
Jan 24, 2:58 PM MST	Special Weather Statement	PSR		32 min
Jan 24, 3:17 PM MST	Special Weather Statement	PSR	Pinal	28 min
Jan 23, 5:42 PM MST	Special Weather Statement	PSR	Imperial	48 min

Nearby

Winter Weather Advisories in Arizona, 2021 Every winter weather advisory in 2021

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.