Alert archive / Arizona / Flash Flood Warnings in 2019

Flash Flood Warning 108, NWS Phoenix, AZ

November 20, 2019Gila County, Maricopa County, Pinal County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Nov 20, 2019, 6:49 PM MST for Gila County, Maricopa County, Pinal 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: Nov 20, 2019, 6:49 PM MST (01:49 UTC)
Expired: Nov 20, 2019, 10:45 PM MST
In force: 4 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Flood severity: None

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 01:52 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 00:00Z, 1.8 hours before the alert went out and 210 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 577 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 191 m²/s²
0-3 km storm-relative helicity: 203 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 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 Nov 20, 5:05 PM MST, 1 hour 44 minutes earlier.

Area forecast discussion, Nov 20, 5:05 PM MST, 1 hour 44 minutes before

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In the hours before

Special weather statement, Nov 20, 5:16 PM MST, 1 hour 33 minutes before

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Special weather statement, Nov 20, 5:17 PM MST, 1 hour 32 minutes before

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Local storm report, Nov 20, 5:23 PM MST, 1 hour 26 minutes before

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Special weather statement, Nov 20, 5:54 PM MST, 55 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Special weather statement, Nov 20, 6:15 PM MST, 34 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
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      <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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Local storm report, Nov 20, 6:44 PM MST, 5 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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The office that day

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

Issued	Product	Office	Counties	Lasted
Nov 20, 5:01 PM MST	Special Weather Statement	PSR	Maricopa	44 min
Nov 20, 5:16 PM MST	Special Weather Statement	PSR	Maricopa	44 min
Nov 20, 5:17 PM MST	Special Weather Statement	PSR		58 min
Nov 20, 5:54 PM MST	Special Weather Statement	PSR		51 min
Nov 20, 6:15 PM MST	Special Weather Statement	PSR	Pinal	45 min
Nov 20, 7:04 PM MST	Special Weather Statement	PSR	Gila	41 min
Nov 21, 10:35 AM MST	Special Weather Statement	PSR	Maricopa	25 min
Nov 21, 10:53 AM MST	Flash Flood Warning	PSR	Maricopa, Pinal	3 hr
Nov 21, 11:05 AM MST	Special Weather Statement	PSR		40 min
Nov 21, 11:45 AM MST	Special Weather Statement	PSR		45 min
Nov 21, 12:05 PM MST	Special Weather Statement	PSR	La Paz	40 min
Nov 21, 12:19 PM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	3 hr
Nov 21, 12:25 PM MST	Special Weather Statement	PSR		50 min
Nov 21, 1:24 PM MST	Special Weather Statement	PSR		36 min
Nov 21, 1:32 PM MST	Special Weather Statement	PSR		43 min
Nov 21, 1:35 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Nov 21, 2:12 PM MST	Special Weather Statement	PSR	Maricopa	48 min
Nov 21, 2:19 PM MST	Special Weather Statement	PSR		41 min
Nov 21, 2:23 PM MST	Special Weather Statement	PSR	Maricopa	52 min
Nov 21, 2:37 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	23 min
Nov 21, 3:01 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	44 min
Nov 21, 3:03 PM MST	Special Weather Statement	PSR		42 min
Nov 21, 3:20 PM MST	Special Weather Statement	PSR	Maricopa	40 min
Nov 21, 3:42 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	48 min
Nov 21, 4:06 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Nov 21, 4:32 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Nov 21, 4:32 PM MST	Special Weather Statement	PSR		43 min

Nearby

Flash Flood Warnings in Arizona, 2019 Every flash flood warning in 2019

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.