Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 32, NWS Phoenix, AZ

July 21, 2021Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Jul 21, 2021, 10:25 PM MST for Maricopa County, Arizona. It was in force for 16 min. 3 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
Jul 21, 2021, 10:25 PM MST (05:25 UTC)
Expired
Jul 21, 2021, 10:41 PM MST
In force
16 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), 35 km from the middle of the area, began a volume at 05:26 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
Jul 21, 10:30 PM MSTHAIL 0.52 Sw Paradise Valley, AZ*** DELAYED REPORT *** SOCIAL MEDIA POST SHOWS ACCUMULATING HAIL ALONG NORTH 53RD ST. BETWEEN EAST PALOMINO RD. AND EAST WONDERVIEW RD. WITH SIZES ESTIMATED TO BE SIMILAR TO NEARBY REPORTS.
Jul 21, 10:30 PM MSTHAIL 0.52 Wsw Scottsdale, AZ*** DELAYED REPORT *** RESPONSE TO SOCIAL MEDIA POST REPORTED HAIL AT NORTH 56TH ST. AND EAST OSBORN RD.
Jul 21, 10:30 PM MSTHAIL 0.53 W Scottsdale, AZ*** DELAYED REPORT *** SOCIAL MEDIA POST SHOWS HANDFUL OF HAIL WITH SIZE ESTIMATED FROM VIDEO NEAR EAST INDIAN SCHOOL RD. AND NORTH 50TH ST.

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, 5.4 hours before the alert went out and 6 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 2021-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 760 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 2021-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 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
760 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
3156 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted.

486 
WUUS55 KPSR 220525
SVRPSR
AZC013-220600-
/O.NEW.KPSR.SV.W.0032.210722T0525Z-210722T0600Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Phoenix AZ
1025 PM MST Wed Jul 21 2021

The National Weather Service in Phoenix has issued a

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

* Until 1100 PM MST.

* At 1025 PM MST, a severe thunderstorm was located over Camelback
  Mountain, or near Paradise Valley, and is nearly stationary.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Phoenix, Scottsdale, Tempe, Paradise Valley, Tempe Marketplace,
  Papago Park, Piestewa Peak Park, Salt River Indian Community, North
  Mountain Park, Downtown Phoenix, Downtown Scottsdale, Arizona State
  University, Camelback Mountain and Sky Harbor Airport.

* This includes the following highways...
  AZ Interstate 10 between mile markers 144 and 155.
  AZ Interstate 17 between mile markers 195 and 196.
  AZ Route 51 between mile markers 1 and 12.

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 3338 11194 3344 11210 3364 11206 3356 11180
TIME...MOT...LOC 0525Z 213DEG 4KT 3349 11196 

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

CK
2 follow-up statements
428 
WWUS55 KPSR 220536
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
1036 PM MST Wed Jul 21 2021

AZC013-220600-
/O.CON.KPSR.SV.W.0032.000000T0000Z-210722T0600Z/
Maricopa AZ-
1036 PM MST Wed Jul 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM MST
FOR MARICOPA COUNTY...

At 1035 PM MST, a severe thunderstorm was located over Camelback
Mountain, or near Paradise Valley, and is nearly stationary.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Phoenix, Scottsdale, Tempe, Paradise Valley, Papago Park, Piestewa
Peak Park, Downtown Phoenix, Downtown Scottsdale, Camelback Mountain
and Sky Harbor Airport.

This includes the following highways...
AZ Interstate 10 between mile markers 145 and 149.
AZ Route 51 between mile markers 1 and 10.
AZ Route 202 between mile markers 1 and 7.

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 3343 11193 3344 11209 3361 11206 3356 11184
TIME...MOT...LOC 0535Z 134DEG 4KT 3350 11200 

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

CK
928 
WWUS55 KPSR 220541
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
1041 PM MST Wed Jul 21 2021

AZC013-220551-
/O.CAN.KPSR.SV.W.0032.000000T0000Z-210722T0600Z/
Maricopa AZ-
1041 PM MST Wed Jul 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR MARICOPA COUNTY IS
CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However small hail, gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 3343 11193 3344 11209 3361 11206 3356 11184
TIME...MOT...LOC 0539Z 213DEG 4KT 3351 11200 

$$

CK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 5:37 PM MSTSpecial Weather StatementPSRYuma38 min
Jul 21, 5:41 PM MSTSpecial Weather StatementPSR49 min
Jul 21, 6:18 PM MSTSevere Thunderstorm WarningPSRLa Paz, Yuma42 min
Jul 21, 6:20 PM MSTSpecial Weather StatementPSRGila40 min
Jul 21, 6:47 PM MSTSpecial Weather StatementPSR43 min
Jul 21, 6:59 PM MSTSpecial Weather StatementPSRYuma46 min
Jul 21, 7:06 PM MSTAreal Flood AdvisoryPSRGila3 hr
Jul 21, 7:10 PM MSTSpecial Weather StatementPSRLa Paz50 min
Jul 21, 7:17 PM MSTAreal Flood AdvisoryPSRYuma44 min
Jul 21, 7:40 PM MSTDust Storm WarningPSRYuma35 min
Jul 21, 8:01 PM MSTFlash Flood Warning Considerable damage threatPSRYuma4 hr
Jul 21, 8:13 PM MSTDust Storm AdvisoryPSRYuma47 min
Jul 21, 9:06 PM MSTDust Storm AdvisoryPSRMaricopa, Pinal39 min
Jul 21, 10:06 PM MSTDust Storm AdvisoryPSRMaricopa, Pinal39 min
Jul 21, 10:11 PM MSTSpecial Weather StatementPSRPinal49 min
Jul 21, 10:23 PM MSTSpecial Weather StatementPSRMaricopa37 min
Jul 21, 10:39 PM MSTSpecial Weather StatementPSR36 min
Jul 21, 10:51 PM MSTSevere Thunderstorm WarningPSRMaricopa24 min
Jul 21, 11:12 PM MSTSpecial Weather StatementPSR48 min
Jul 21, 11:15 PM MSTSpecial Weather StatementPSRPinal45 min
Jul 22, 12:28 AM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Jul 22, 12:32 AM MSTAreal Flood AdvisoryPSRMaricopa118 min
Jul 22, 3:06 PM MSTSpecial Weather StatementPSR54 min
Jul 22, 3:43 PM MSTSpecial Weather StatementPSRMaricopa47 min
Jul 22, 3:58 PM MSTSevere Thunderstorm WarningPSRMaricopa33 min
Jul 22, 4:30 PM MSTDust Storm AdvisoryPSRYuma41 min
Jul 22, 4:53 PM MSTAreal Flood AdvisoryPSRMaricopa3 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.