Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 73, NWS Phoenix, AZ

August 14, 2021Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 14, 2021, 6:22 PM MST for Maricopa County, Arizona. It was in force for 38 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 14, 2021, 6:22 PM MST (01:22 UTC)
Expired
Aug 14, 2021, 7:00 PM MST
In force
38 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 60 km from the middle of the area, began a volume at 01:23 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, 1.4 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-pSkew-T log-p diagram, Phoenix, AZ at 00:00Z on 2021-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1092 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
1092 J/kg
Mixed-layer CIN
-58 J/kg
Mixed-layer LCL
1640 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
106 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

060 
WUUS55 KPSR 150122
SVRPSR
AZC013-150200-
/O.NEW.KPSR.SV.W.0073.210815T0122Z-210815T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Phoenix AZ
622 PM MST Sat Aug 14 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 622 PM MST, severe thunderstorms were located along a line
  extending from near Horseshoe Reservoir to near Desert Mountain to
  Rio Verde, moving southwest at 25 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Phoenix, Scottsdale, Fountain Hills, New River, Cave Creek,
  Carefree, McDowell Mountain Park, Desert Mountain, Scottsdale
  Airport, Desert Ridge Marketplace, Camp Creek, Rio Verde, Horseshoe
  Reservoir, Seven Springs and Fort McDowell.

This includes the following highways...
AZ Route 51 near mile marker 15.
AZ Route 101 between mile markers 29 and 40.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3399 11157 3383 11162 3370 11158 3354 11182
      3370 11208 3403 11199
TIME...MOT...LOC 0122Z 062DEG 23KT 3399 11168 3381 11176 3370 11169 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

DH
1 follow-up statement
132 
WWUS55 KPSR 150154
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
654 PM MST Sat Aug 14 2021

AZC013-150204-
/O.EXP.KPSR.SV.W.0073.000000T0000Z-210815T0200Z/
Maricopa AZ-
654 PM MST Sat Aug 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR MARICOPA COUNTY WILL EXPIRE AT
700 PM MST...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

LAT...LON 3399 11157 3383 11162 3370 11158 3354 11182
      3370 11208 3403 11199
TIME...MOT...LOC 0154Z 062DEG 23KT 3390 11189 3372 11197 3361 11190 

$$

DH

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 5:26 PM MSTSpecial Weather StatementPSR49 min
Aug 14, 5:46 PM MSTSpecial Weather StatementPSR44 min
Aug 14, 5:51 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa24 min
Aug 14, 6:17 PM MSTSpecial Weather StatementPSR43 min
Aug 14, 6:33 PM MSTSpecial Weather StatementPSR42 min
Aug 14, 6:36 PM MSTSpecial Weather StatementPSR39 min
Aug 14, 6:45 PM MSTSpecial Weather StatementPSRMaricopa45 min
Aug 14, 6:53 PM MSTSpecial Weather StatementPSR52 min
Aug 14, 7:17 PM MSTSpecial Weather StatementPSR43 min
Aug 14, 7:19 PM MSTSpecial Weather StatementPSR41 min
Aug 14, 11:13 PM MSTSpecial Weather StatementPSRLa Paz47 min
Aug 14, 11:17 PM MSTSpecial Weather StatementPSRLa Paz43 min
Aug 14, 11:26 PM MSTSpecial Weather StatementPSR64 min
Aug 15, 12:55 AM MSTSpecial Weather StatementPSR65 min
Aug 15, 4:42 AM MSTAreal Flood AdvisoryPSRMaricopa, Yuma6 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.