Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 77, NWS Phoenix, AZ

August 15, 2021Maricopa County, Pinal County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 15, 2021, 10:31 PM MST for Maricopa County, Pinal County, Arizona. It was in force for 44 min. 5 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 15, 2021, 10:31 PM MST (05:31 UTC)
Expired: Aug 15, 2021, 11:15 PM MST
In force: 44 min
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Maricopa County, AZ, Pinal County, AZ

The radar

The Phoenix radar (KIWA), 15 km from the middle of the area, began a volume at 05:33 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

Time	Report	Where	Remark
Aug 15, 10:40 PM MST	HAIL 0.25	3 Ne East Mesa, AZ
Aug 15, 10:44 PM MST	TSTM WND GST 51	4 Nw East Mesa, AZ	MESA FALCON FIELD ASOS.
Aug 15, 10:45 PM MST	TSTM WND GST 46	2 N East Mesa, AZ	0.45 INCHES OF RAIN WITHIN 15 MINUTES.
Aug 15, 10:48 PM MST	TSTM WND DMG	3 Wnw East Mesa, AZ	*DELAYED REPORT*LARGE PINE TREE 2-3 FEET IN DIAMETER FELL ON TOP OF GARAGE AND VEHICLE NEAR UNIVERSITY AND GREENFIELD. TIME ESTIMATED BY RADAR.
Aug 15, 10:53 PM MST	TSTM WND DMG	4 E Mesa, AZ	*DELAYED REPORT*MULTIPLE LARGE PINE TREES AND POWER POLES BLOWN DOWN AT APARTMENT COMPLEX NEAR UNIVERSITY DR. AND LA VALENCIA TO LINDSEY RD. TIME ESTIMATED BY RADAR.

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, 5.5 hours before the alert went out and 25 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: 1548 J/kg
Mixed-layer CIN: -94 J/kg
Mixed-layer LCL: 2123 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -22 m²/s²
0-3 km storm-relative helicity: 56 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted.

158 
WUUS55 KPSR 160531
SVRPSR
AZC013-021-160615-
/O.NEW.KPSR.SV.W.0077.210816T0531Z-210816T0615Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Phoenix AZ
1031 PM MST Sun Aug 15 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 1115 PM MST.

* At 1030 PM MST, a severe thunderstorm was located over Usery
  Mountain Park, or near East Mesa, moving southwest at 20 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Mesa, Chandler, Gilbert, Tempe, Apache Junction, Fountain Hills,
  Sun Lakes, East Mesa, Queen Creek, Tempe Marketplace, Granite Reef
  Dam, Falcon Field Airport, Salt River Indian Community, Lost
  Dutchman State Park and Goldfield.

This includes the following highways...
AZ Interstate 10 between mile markers 159 and 167.
US Highway 60 between mile markers 174 and 198.
AZ Route 87 between mile markers 153 and 195.

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 this storm. 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 this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3362 11164 3349 11143 3329 11158 3312 11176
      3328 11202 3352 11184
TIME...MOT...LOC 0530Z 036DEG 19KT 3347 11166 

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

$$

SDB

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 15, 7:49 PM MST	Special Weather Statement	PSR	Gila	56 min
Aug 15, 8:26 PM MST	Severe Thunderstorm Warning	PSR	Gila	49 min
Aug 15, 9:14 PM MST	Severe Thunderstorm Warning	PSR	Gila, Maricopa, Pinal	46 min
Aug 15, 9:18 PM MST	Special Weather Statement	PSR	Gila	42 min
Aug 15, 9:58 PM MST	Severe Thunderstorm Warning Considerable damage threat	PSR	Gila, Maricopa, Pinal	47 min
Aug 15, 10:14 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Aug 15, 10:45 PM MST	Special Weather Statement	PSR	Pinal	45 min
Aug 15, 10:50 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Maricopa, Pinal	6 hr
Aug 15, 10:55 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	65 min
Aug 15, 10:58 PM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	3 hr
Aug 15, 11:14 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	46 min
Aug 15, 11:31 PM MST	Special Weather Statement	PSR	Maricopa	44 min
Aug 15, 11:37 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	38 min
Aug 15, 11:44 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	32 min
Aug 15, 11:45 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Aug 16, 12:18 AM MST	Special Weather Statement	PSR		42 min
Aug 16, 12:49 AM MST	Severe Thunderstorm Warning	PSR	La Paz, Maricopa	56 min
Aug 16, 1:33 AM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz, Maricopa	6 hr
Aug 16, 1:47 AM MST	Special Weather Statement	PSR	La Paz	58 min
Aug 16, 1:54 AM MST	Severe Thunderstorm Warning	PSR	La Paz	66 min
Aug 16, 2:22 AM MST	Special Weather Statement	PSR	La Paz	68 min
Aug 16, 2:53 AM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz	5 hr
Aug 16, 3:08 AM MST	Dust Storm Advisory	PSR	La Paz, Yuma	2 hr

Nearby

Severe Thunderstorm Warnings in Arizona, 2021 Every 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.