Alert archive / Arizona / Areal Flood Warnings in 2021

Areal Flood Warning 20, NWS Phoenix, AZ

August 17, 2021Gila County, Arizona

NWS Phoenix, AZ issued this areal flood warning at Aug 17, 2021, 8:42 AM MST for Gila County, Arizona. It was in force for 5 days. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 17, 2021, 8:42 AM MST (15:42 UTC)
Expired: Aug 22, 2021, 12:00 PM MST
In force: 5 days
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Flood severity: None

County Gila County, AZ

The radar

The Flagstaff radar (KFSX), 93 km from the middle of the area, began a volume at 15:41 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

Phoenix, AZ (KPSR), launched 12:00Z, 3.7 hours before the alert went out and 115 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: 14 J/kg
Mixed-layer CIN: -428 J/kg
Mixed-layer LCL: 1452 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 154 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.3

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood warning 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 areal flood warning went out at Aug 17, 6:25 AM MST, 2 hours 17 minutes earlier.

Area forecast discussion, Aug 17, 6:25 AM MST, 2 hours 17 minutes before

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In the hours before

Local storm report, Aug 17, 3:14 AM MST, 5 hours 28 minutes before

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<body>
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    <section class="card" role="status" aria-live="polite">
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Local storm report, Aug 17, 5:10 AM MST, 3 hours 32 minutes before

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<head>
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  <title>Service Notice</title>
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</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.
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      <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, Aug 17, 5:29 AM MST, 3 hours 13 minutes before

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<head>
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  <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>

Local storm report, Aug 17, 5:30 AM MST, 3 hours 12 minutes before

<!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>

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 16, 5:15 PM MST	Special Weather Statement	PSR	Gila	45 min
Aug 16, 5:46 PM MST	Special Weather Statement	PSR		44 min
Aug 16, 6:07 PM MST	Special Weather Statement	PSR	Gila	38 min
Aug 16, 6:14 PM MST	Severe Thunderstorm Warning	PSR	Gila	46 min
Aug 16, 6:37 PM MST	Special Weather Statement	PSR	Pinal	53 min
Aug 16, 6:55 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	6 hr
Aug 16, 8:24 PM MST	Special Weather Statement	PSR		51 min
Aug 16, 8:41 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	5 hr
Aug 16, 8:53 PM MST	Special Weather Statement	PSR	Gila	52 min
Aug 16, 9:08 PM MST	Special Weather Statement	PSR	Gila	52 min
Aug 16, 9:22 PM MST	Severe Thunderstorm Warning	PSR	Gila, Maricopa, Pinal	38 min
Aug 16, 9:41 PM MST	Severe Thunderstorm Warning	PSR	Gila, Maricopa, Pinal	49 min
Aug 16, 9:49 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	Gila, Maricopa	41 min
Aug 16, 10:01 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Aug 16, 10:01 PM MST	Special Weather Statement	PSR		44 min
Aug 16, 10:05 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Aug 16, 10:14 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	Gila, Maricopa, Pinal	46 min
Aug 16, 10:22 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	10 hr
Aug 16, 10:28 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Maricopa, Pinal	10 hr
Aug 16, 10:36 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Maricopa	10 hr
Aug 16, 10:38 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	67 min
Aug 16, 10:48 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	9 hr
Aug 16, 10:54 PM MST	Severe Thunderstorm Warning Destructive damage threat	PSR	Maricopa, Pinal	51 min
Aug 16, 10:58 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	7 hr
Aug 16, 11:04 PM MST	Dust Storm Warning	PSR	Maricopa, Pinal	56 min
Aug 16, 11:07 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	7 hr
Aug 16, 11:16 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	7 hr
Aug 16, 11:26 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	8 hr
Aug 16, 11:31 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	44 min
Aug 16, 11:41 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	Maricopa, Pinal	49 min
Aug 16, 11:47 PM MST	Dust Storm Warning	PSR	Maricopa	58 min
Aug 16, 11:50 PM MST	Special Weather Statement	PSR		40 min
Aug 16, 11:52 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	38 min
Aug 16, 11:56 PM MST	Flash Flood Warning Considerable damage threat	PSR	Pinal	7 hr
Aug 16, 11:59 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	6 hr
Aug 17, 12:01 AM MST	Dust Storm Warning	PSR	Maricopa, Pinal	59 min
Aug 17, 12:09 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	8 hr
Aug 17, 12:32 AM MST	Special Weather Statement	PSR		43 min
Aug 17, 12:36 AM MST	Special Weather Statement	PSR	Maricopa	24 min
Aug 17, 4:05 AM MST	Areal Flood Advisory	PSR	Maricopa	4 hr
Aug 17, 4:26 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	6 hr
Aug 17, 5:29 AM MST	Special Weather Statement	PSR	Maricopa	76 min
Aug 17, 5:35 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	6 hr
Aug 17, 6:26 AM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Pinal	5 hr
Aug 17, 4:46 PM MST	Special Weather Statement	PSR		44 min

Nearby

Areal Flood Warnings in Arizona, 2021 Every areal flood warning 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.