Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 21, NWS Phoenix, AZ

July 10, 2021Maricopa County, Pinal County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Jul 10, 2021, 8:16 PM MST for Maricopa County, Pinal County, Arizona. It was in force for 44 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
Jul 10, 2021, 8:16 PM MST (03:16 UTC)
Expired
Jul 10, 2021, 9:00 PM MST
In force
44 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Maricopa County, AZ, Pinal County, AZ

The radar

The Phoenix radar (KIWA), 50 km from the middle of the area, began a volume at 03:15 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 10, 8:35 PM MSTTSTM WND GST 609 Se Maricopa, AZREPORTED AT AK-CHIN RGNL AIRPORT.
Jul 10, 8:40 PM MSTTSTM WND DMGMaricopa, AZ***DELAYED REPORT*** TOP HALF OF A 20 FT VERTICAL ANTENNA MAST TOPPLED OVER.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 10, 4:52 PM MSTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 3.3 hours before the alert went out and 52 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 2021-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 965 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 2021-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 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
965 J/kg
Mixed-layer CIN
-311 J/kg
Mixed-layer LCL
3378 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

425 
WUUS55 KPSR 110316
SVRPSR
AZC013-021-110400-
/O.NEW.KPSR.SV.W.0021.210711T0316Z-210711T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Phoenix AZ
816 PM MST Sat Jul 10 2021

The National Weather Service in Phoenix has issued a

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

* Until 900 PM MST.

* At 816 PM MST, severe thunderstorms were located along a line
  extending from Falcon Field Airport to Queen Creek to Blackwater,
  moving west at 20 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Phoenix, Mesa, Chandler, Glendale, Scottsdale, Gilbert, Tempe,
  Avondale, Goodyear, Buckeye, Casa Grande, Apache Junction, Paradise
  Valley, Coolidge and Tolleson.

* This includes the following highways...
  AZ Interstate 10 between mile markers 121 and 199.
  AZ Interstate 17 between mile markers 195 and 209.
  AZ Interstate 8 between mile markers 135 and 178.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with these storms. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

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

&&

LAT...LON 3296 11250 3343 11256 3360 11223 3353 11161
      3327 11147 3295 11147 3276 11176 3280 11178
      3276 11205 3273 11205 3272 11214 3268 11215
      3268 11220 3264 11224
TIME...MOT...LOC 0316Z 078DEG 19KT 3344 11170 3323 11165 3301 11156 

HAIL...0.75IN
WIND...60MPH
 
$$

SDB
1 follow-up statement
865 
WWUS55 KPSR 110341
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
841 PM MST Sat Jul 10 2021

AZC013-021-110400-
/O.CON.KPSR.SV.W.0021.000000T0000Z-210711T0400Z/
Maricopa AZ-Pinal AZ-
841 PM MST Sat Jul 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM MST
FOR MARICOPA AND PINAL COUNTIES...

At 840 PM MST, the leading edge of very strong outflow winds from 
thunderstorms was located along a line extending from 7 miles west 
of South Mountain Park to 11 miles southeast of Estrella Mountain 
Park to near Estrella Sailport to 11 miles east of Freeman, moving 
west at 40 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Phoenix, Mesa, Chandler, Glendale, Scottsdale, Gilbert, Tempe,
Avondale, Goodyear, Buckeye, Casa Grande, Apache Junction, Paradise
Valley, Coolidge and Tolleson.

This includes the following highways...
AZ Interstate 10 between mile markers 121 and 199.
AZ Interstate 17 between mile markers 195 and 209.
AZ Interstate 8 between mile markers 135 and 178.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 3296 11250 3343 11256 3360 11223 3353 11161
      3327 11147 3295 11147 3276 11176 3280 11178
      3276 11205 3273 11205 3272 11214 3268 11215
      3268 11220 3264 11224
TIME...MOT...LOC 0340Z 075DEG 35KT 3332 11220 3320 11223 3306 11220
3288 11211

HAIL...0.75IN
WIND...70MPH
 
$$

SDB

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 10, 5:37 PM MSTSpecial Weather StatementPSRGila38 min
Jul 10, 5:45 PM MSTSevere Thunderstorm WarningPSRGila45 min
Jul 10, 6:06 PM MSTSpecial Weather StatementPSRGila39 min
Jul 10, 6:24 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa, Pinal36 min
Jul 10, 6:42 PM MSTSevere Thunderstorm WarningPSRMaricopa33 min
Jul 10, 7:00 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa, Pinal45 min
Jul 10, 7:10 PM MSTFlash Flood Warning Considerable damage threatPSRGila4 hr
Jul 10, 7:12 PM MSTSevere Thunderstorm WarningPSRMaricopa33 min
Jul 10, 7:27 PM MSTDust Storm WarningPSRMaricopa63 min
Jul 10, 7:31 PM MSTDust Storm WarningPSRMaricopa, Pinal59 min
Jul 10, 7:45 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal30 min
Jul 10, 8:29 PM MSTDust Storm WarningPSRMaricopa, Pinal91 min
Jul 10, 8:42 PM MSTAreal Flood AdvisoryPSRMaricopa, Pinal3 hr
Jul 10, 9:00 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal45 min
Jul 10, 9:48 PM MSTSpecial Weather StatementPSR57 min
Jul 10, 9:54 PM MSTSpecial Weather StatementPSRPinal36 min
Jul 10, 10:25 PM MSTSpecial Weather StatementPSR35 min
Jul 10, 10:31 PM MSTDust Storm AdvisoryPSRMaricopa, Yuma89 min
Jul 10, 10:43 PM MSTDust Storm WarningPSRMaricopa, Yuma62 min
Jul 10, 11:19 PM MSTDust Storm WarningPSRYuma56 min

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.