Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 53, NWS Phoenix, AZ

August 11, 2021Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 11, 2021, 6:19 PM MST for Maricopa County, Arizona. It was in force for 41 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 11, 2021, 6:19 PM MST (01:19 UTC)
Expired
Aug 11, 2021, 7:00 PM MST
In force
41 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 70 km from the middle of the area, began a volume at 01:20 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.

What was reported inside it

TimeReportWhereRemark
Aug 11, 6:50 PM MSTTSTM WND DMG2 E Litchfield Park, AZ**DELAYED REPORT** SEVERAL LARGE TREES DOWNED ACROSS THE NEIGHBORHOOD. MINOR ROOF DAMAGE (TWO HOMES WITH APPROX 5-10 TILES DAMAGED EACH). REPORTS RECEIVED AND VERIFIED THROUGH SOCIAL MEDIA. T-STORM ESTIMATED WIND GUSTS 55-65 MPH.
Aug 11, 7:10 PM MSTTSTM WND GST 504 E Litchfield Park, AZTREE BLOWN OVER FROM ESTIMATED WINDS OF 45-50 MPH.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 1.3 hours before the alert went out and 41 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-pSkew-T log-p diagram, Phoenix, AZ at 00:00Z on 2021-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1157 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2021-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1157 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1687 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

534 
WUUS55 KPSR 120119
SVRPSR
AZC013-120200-
/O.NEW.KPSR.SV.W.0053.210812T0119Z-210812T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Phoenix AZ
619 PM MST Wed Aug 11 2021

The National Weather Service in Phoenix has issued a

* Severe Thunderstorm Warning for...
  Maricopa County in south central Arizona...

* Until 700 PM MST.

* At 618 PM MST, a severe thunderstorm was located over Goodyear,
  moving east at 10 mph.

  HAZARD...60 mph wind gusts. Small hail.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Glendale, Avondale, Goodyear, Buckeye, El Mirage, Tolleson, 
  Youngtown, Sun City, Litchfield Park, west Phoenix, and Luke AFB.

This includes the following highways...
AZ Interstate 10 between mile markers 120 and 134.
AZ Route 101 near mile marker 2.
AZ Route 303 between mile markers 105 and 110.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3335 11250 3353 11253 3358 11229 3332 11223
TIME...MOT...LOC 0118Z 259DEG 9KT 3344 11240 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

AJ
2 follow-up statements
916 
WWUS55 KPSR 120122
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
622 PM MST Wed Aug 11 2021

AZC013-120200-
/O.CON.KPSR.SV.W.0053.000000T0000Z-210812T0200Z/
Maricopa AZ-
622 PM MST Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM MST
FOR MARICOPA COUNTY...

At 621 PM MST, a severe thunderstorm was located over Goodyear,
moving east at 10 mph.

HAZARD...60 mph wind gusts and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Glendale, Avondale, Goodyear, Buckeye, El Mirage, Tolleson, 
Youngtown, Sun City, Litchfield Park, west Phoenix, and Luke 
AFB.

This includes the following highways...
AZ Interstate 10 between mile markers 120 and 134.
AZ Route 101 near mile marker 2.
AZ Route 303 between mile markers 105 and 110.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3335 11250 3353 11253 3358 11229 3332 11223
TIME...MOT...LOC 0121Z 259DEG 9KT 3344 11239 

HAIL...0.88IN
WIND...60MPH
 
$$

AJ
773 
WWUS55 KPSR 120151
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
651 PM MST Wed Aug 11 2021

AZC013-120200-
/O.CON.KPSR.SV.W.0053.000000T0000Z-210812T0200Z/
Maricopa AZ-
651 PM MST Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM MST
FOR MARICOPA COUNTY...

At 650 PM MST, a severe thunderstorm was located over Avondale, 
moving east at 10 mph.

HAZARD...60 mph wind gusts. Small hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Glendale, Avondale, Goodyear, Buckeye, El Mirage, Tolleson, 
Youngtown, Cashion, Sun City, Litchfield Park, and Luke AFB.

This includes the following highways...
AZ Interstate 10 between mile markers 120 and 134.
AZ Route 101 near mile marker 2.
AZ Route 303 between mile markers 105 and 110.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3335 11250 3353 11253 3358 11229 3332 11223
TIME...MOT...LOC 0150Z 259DEG 9KT 3345 11230 

HAIL...<.75IN
WIND...60MPH
 
$$

AJ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 5:03 PM MSTSevere Thunderstorm WarningPSRMaricopa42 min
Aug 11, 5:14 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa3 hr
Aug 11, 5:14 PM MSTSpecial Weather StatementPSRMaricopa46 min
Aug 11, 5:30 PM MSTFlash Flood WarningPSRMaricopa2 hr
Aug 11, 5:30 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal45 min
Aug 11, 5:39 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa3 hr
Aug 11, 5:49 PM MSTSpecial Weather StatementPSR41 min
Aug 11, 5:57 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa6 hr
Aug 11, 6:07 PM MSTDust Storm WarningPSRMaricopa, Pinal53 min
Aug 11, 6:12 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal48 min
Aug 11, 6:20 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Aug 11, 6:40 PM MSTFlash Flood WarningPSRMaricopa4 hr
Aug 11, 7:02 PM MSTSpecial Weather StatementPSR58 min
Aug 11, 7:11 PM MSTSpecial Weather StatementPSR64 min
Aug 11, 7:26 PM MSTFlash Flood Warning Considerable damage threatPSRLa Paz3 hr
Aug 11, 7:53 PM MSTSpecial Weather StatementPSRLa Paz37 min
Aug 12, 2:00 AM MSTSpecial Weather StatementPSR45 min
Aug 12, 2:42 AM MSTFlash Flood Warning Considerable damage threatPSRGila, Maricopa4 hr
Aug 12, 2:45 AM MSTAreal Flood AdvisoryPSRMaricopa3 hr
Aug 12, 3:34 AM MSTAreal Flood AdvisoryPSRMaricopa3 hr
Aug 12, 4:16 AM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Aug 12, 4:33 AM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Aug 12, 5:17 AM MSTFlash Flood Warning Considerable damage threatPSRMaricopa6 hr
Aug 12, 6:04 AM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Aug 12, 6:21 AM MSTAreal Flood AdvisoryPSRMaricopa46 min
Aug 12, 7:00 AM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Aug 12, 10:09 AM MSTAreal Flood WarningPSRGila8 hr
Aug 12, 10:46 AM MSTAreal Flood WarningPSRMaricopa15 hr
Aug 12, 1:30 PM MSTFlash Flood WatchPSRGila, Maricopa, Pinal5 days
Aug 12, 2:11 PM MSTSpecial Weather StatementPSRLa Paz34 min
Aug 12, 2:30 PM MSTAreal Flood AdvisoryPSRMaricopa3 hr
Aug 12, 2:45 PM MSTAreal Flood AdvisoryPSRLa Paz3 hr
Aug 12, 2:54 PM MSTFlash Flood Warning Considerable damage threatPSRLa Paz, Maricopa4 hr
Aug 12, 3:11 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa5 hr
Aug 12, 3:34 PM MSTSpecial Weather StatementPSR41 min
Aug 12, 4:14 PM MSTAreal Flood AdvisoryPSRMaricopa, Yuma3 hr

Nearby

Severe Thunderstorm Warnings in Arizona, 2021Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.