Alert archive / Arizona / Flash Flood Warnings in 2022

Flash Flood Warning 287, NWS Phoenix, AZ

September 21, 2022Yuma County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Sep 21, 2022, 4:36 PM MST for Yuma County, Arizona. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 21, 2022, 4:36 PM MST (23:36 UTC)
Expired: Sep 21, 2022, 8:45 PM MST
In force: 4 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Yuma County, AZ

The radar

The Yuma radar (KYUX), 77 km from the middle of the area, began a volume at 23:39 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, 11.6 hours before the alert went out and 195 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: 211 J/kg
Mixed-layer CIN: -110 J/kg
Mixed-layer LCL: 1250 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 46 m²/s²
0-3 km storm-relative helicity: 117 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash 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 flash flood warning went out at Sep 21, 2:31 PM MST, 2 hours 5 minutes earlier.

Area forecast discussion, Sep 21, 2:31 PM MST, 2 hours 5 minutes before

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In the hours before

Local storm report, Sep 21, 10:41 AM MST, 5 hours 55 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
1041 AM MST WED SEP 21 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1005 AM     FLASH FLOOD      5 NW BEARDSLEY          33.73N 112.46W
09/21/2022                   MARICOPA           AZ   BROADCAST MEDIA

            MEDIA REPORTS FLASH FLOODING NEAR WITTMAN.
            WATER AND DEBRIS FLOWING OVER RAODWAY OFF OF
            GRAND AVE & JOMAX.

&&

BF

Local storm report, Sep 21, 11:46 AM MST, 4 hours 50 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
1146 AM MST WED SEP 21 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1124 AM     FLASH FLOOD      9 SSE PALO VERDE NGS    33.28N 112.80W
09/21/2022                   MARICOPA           AZ   MESONET

            CENTENNIAL WASH @ SPRR ID 24707 REACHED
            ACTION STAGE AT 9:54 AM MST. FLASH FLOOD
            IMPACTS DOWNSTREAM WHERE CENTENNIAL WASH
            CROSSES OLD U.S. 80 1.5 HOURS AFTER ACTION
            STAGE WAS REACHED.

&&

BF

Local storm report, Sep 21, 1:57 PM MST, 2 hours 39 minutes before

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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.
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      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Local storm report, Sep 21, 2:21 PM MST, 2 hours 15 minutes before

<!doctype html>
<html lang="en">
<head>
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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.
      </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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Local storm report, Sep 21, 3:26 PM MST, 1 hour 10 minutes before

<!doctype html>
<html lang="en">
<head>
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  <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.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 21, 5:19 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Sep 21, 5:35 AM MST	Special Weather Statement	PSR	Maricopa	25 min
Sep 21, 6:13 AM MST	Special Weather Statement	PSR	Maricopa	32 min
Sep 21, 6:20 AM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Sep 21, 7:00 AM MST	Areal Flood Advisory	PSR	Maricopa	14 min
Sep 21, 7:14 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	3 hr
Sep 21, 7:59 AM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Sep 21, 10:12 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	6 hr
Sep 21, 10:50 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	3 hr
Sep 21, 12:58 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Sep 21, 1:18 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	8 hr
Sep 21, 1:41 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Sep 21, 4:43 PM MST	Flash Flood Warning Considerable damage threat	PSR	Yuma	4 hr
Sep 21, 4:48 PM MST	Special Weather Statement	PSR	La Paz	42 min
Sep 21, 4:52 PM MST	Special Weather Statement	PSR	La Paz	38 min

Nearby

Flash Flood Warnings in Arizona, 2022 Every flash flood warning in 2022

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.