Alert archive / Arizona / Areal Flood Warnings in 2021

Areal Flood Warning 18, NWS Phoenix, AZ

August 14, 2021Maricopa County, Arizona

NWS Phoenix, AZ issued this areal flood warning at Aug 14, 2021, 3:44 AM MST for Maricopa County, Arizona. It was in force for 11 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: Aug 14, 2021, 3:44 AM MST (10:44 UTC)
Expired: Aug 14, 2021, 2:45 PM MST
In force: 11 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Flood severity: None

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 77 km from the middle of the area, began a volume at 10:46 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 00:00Z, 10.7 hours before the alert went out and 49 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: 1603 J/kg
Mixed-layer CIN: -40 J/kg
Mixed-layer LCL: 2033 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 78 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 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 14, 3:26 AM MST, 18 minutes earlier.

Area forecast discussion, Aug 14, 3:26 AM MST, 18 minutes before

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In the hours before

Local storm report, Aug 14, 1:43 AM MST, 2 hours 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
143 AM MST SAT AUG 14 2021

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

0111 AM     FLASH FLOOD      2 SE BOUSE              33.90N 113.97W
08/14/2021                   LA PAZ             AZ   LAW ENFORCEMENT

            HIGHWAY 72 WAS FLOODED AND IMPASSABLE.

&&

PI

Local storm report, Aug 14, 1:53 AM MST, 1 hour 51 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
153 AM MST SAT AUG 14 2021

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

0153 AM     DUST STORM       3 NE TACNA              32.72N 113.92W
08/14/2021                   YUMA               AZ   TRAINED SPOTTER

            LESS THAN 1/4 MILE VISIBILITY WITH ESTIMATED
            40 MPH WIND GUST.

&&

PI

Special weather statement, Aug 14, 2:26 AM MST, 1 hour 18 minutes before

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Local storm report, Aug 14, 2:30 AM MST, 1 hour 14 minutes before

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Local storm report, Aug 14, 2:36 AM MST, 1 hour 8 minutes before

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      <div class="status" id="status">Temporary Notice</div>
      <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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Local storm report, Aug 14, 3:21 AM MST, 23 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 13, 5:14 PM MST	Severe Thunderstorm Warning	PSR	Gila, Maricopa, Pinal	46 min
Aug 13, 5:57 PM MST	Special Weather Statement	PSR	Pinal	48 min
Aug 13, 8:34 PM MST	Special Weather Statement	PSR		41 min
Aug 13, 8:58 PM MST	Special Weather Statement	PSR		47 min
Aug 13, 9:03 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	42 min
Aug 13, 9:19 PM MST	Severe Thunderstorm Warning	PSR	Gila, Maricopa	41 min
Aug 13, 9:38 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	52 min
Aug 13, 9:49 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Maricopa	4 hr
Aug 13, 9:54 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	51 min
Aug 13, 9:56 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Aug 13, 9:58 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	Gila, Maricopa, Pinal	47 min
Aug 13, 10:02 PM MST	Dust Storm Warning	PSR	La Paz, Maricopa	58 min
Aug 13, 10:05 PM MST	Special Weather Statement	PSR	Pinal	40 min
Aug 13, 10:11 PM MST	Special Weather Statement	PSR	Maricopa	49 min
Aug 13, 10:16 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Pinal	44 min
Aug 13, 10:19 PM MST	Flash Flood Warning	PSR	Maricopa	5 hr
Aug 13, 10:24 PM MST	Severe Thunderstorm Warning	PSR	La Paz, Maricopa	36 min
Aug 13, 10:31 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Maricopa	4 hr
Aug 13, 10:39 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Aug 13, 10:44 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	Gila, Maricopa, Pinal	46 min
Aug 13, 10:58 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	5 hr
Aug 13, 11:01 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	La Paz, Maricopa, Yuma	44 min
Aug 13, 11:05 PM MST	Dust Storm Warning	PSR	La Paz, Maricopa, Yuma	55 min
Aug 13, 11:11 PM MST	Special Weather Statement	PSR	Maricopa	49 min
Aug 13, 11:14 PM MST	Flash Flood Warning	PSR	Maricopa, Pinal	5 hr
Aug 13, 11:25 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	65 min
Aug 13, 11:31 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	5 hr
Aug 13, 11:31 PM MST	Severe Thunderstorm Warning	PSR	Gila	44 min
Aug 13, 11:32 PM MST	Special Weather Statement	PSR	Maricopa	58 min
Aug 13, 11:43 PM MST	Severe Thunderstorm Warning	PSR	La Paz, Maricopa, Yuma	47 min
Aug 13, 11:49 PM MST	Special Weather Statement	PSR	La Paz	41 min
Aug 13, 11:51 PM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz	4 hr
Aug 14, 12:03 AM MST	Dust Storm Advisory	PSR	La Paz, Maricopa, Yuma	57 min
Aug 14, 12:15 AM MST	Special Weather Statement	PSR	Gila	45 min
Aug 14, 12:32 AM MST	Special Weather Statement	PSR	Yuma	43 min
Aug 14, 12:33 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	4 hr
Aug 14, 12:35 AM MST	Special Weather Statement	PSR	Maricopa	40 min
Aug 14, 12:53 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Aug 14, 1:03 AM MST	Severe Thunderstorm Warning	PSR	Maricopa, Yuma	57 min
Aug 14, 1:04 AM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz, Maricopa, Yuma	4 hr
Aug 14, 1:20 AM MST	Special Weather Statement	PSR	Maricopa	40 min
Aug 14, 1:37 AM MST	Special Weather Statement	PSR	Yuma	38 min
Aug 14, 1:54 AM MST	Dust Storm Warning	PSR	La Paz, Yuma	51 min
Aug 14, 2:26 AM MST	Special Weather Statement	PSR	Yuma	49 min
Aug 14, 3:35 AM MST	Areal Flood Warning	PSR	Maricopa	6 hr
Aug 14, 12:17 PM MST	Areal Flood Warning	PSR	Maricopa	6 hr
Aug 14, 1:19 PM MST	Flash Flood Warning Considerable damage threat	PSR	Pinal	4 hr
Aug 14, 2:59 PM MST	Special Weather Statement	PSR	Gila	46 min
Aug 14, 3:26 PM MST	Areal Flood Advisory	PSR	Gila	3 hr
Aug 14, 4:55 PM MST	Special Weather Statement	PSR	Gila	50 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.