Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Phoenix, AZ

August 6, 2021

NWS Phoenix, AZ issued this special weather statement at Aug 6, 2021, 5:48 PM MST. It was in force for 27 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 6, 2021, 5:48 PM MST (00:48 UTC)
Expired: Aug 6, 2021, 6:15 PM MST
In force: 27 min
Issued by: NWS Phoenix, AZ
Hail: 0.00 in
Wind: 40

The radar

The Phoenix radar (KIWA), 81 km from the middle of the area, began a volume at 00:51 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, 0.8 hours before the alert went out and 80 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: 1295 J/kg
Mixed-layer CIN: -41 J/kg
Mixed-layer LCL: 2938 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -12 m²/s²
0-3 km storm-relative helicity: -10 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

690 
WWUS85 KPSR 070048
SPSPSR

Special Weather Statement
National Weather Service Phoenix AZ
548 PM MST Fri Aug 6 2021
 
AZZ554-559-070115-
Sonoran Desert Natl Monument AZ-West Pinal County AZ-
548 PM MST Fri Aug 6 2021

...A strong thunderstorm will impact portions of Maricopa and Pinal
Counties through 615 PM MST...

At 546 PM MST, Doppler radar was tracking a strong thunderstorm 7
miles south of Freeman, or 29 miles southeast of Gila Bend. This
storm was nearly stationary.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

Locations impacted include...
Freeman.

This includes AZ Interstate 8 between mile markers 138 and 150.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3279 11237 3287 11237 3286 11215 3272 11214
      3269 11215 3268 11220 3266 11221 3267 11233
TIME...MOT...LOC 0046Z 246DEG 4KT 3274 11225 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

$$

INS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 6, 6:40 PM MST	Special Weather Statement	PSR		35 min
Aug 6, 6:43 PM MST	Dust Storm Advisory	PSR	Pinal	50 min
Aug 6, 6:47 PM MST	Severe Thunderstorm Warning	PSR	Pinal	28 min
Aug 6, 6:56 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	64 min
Aug 6, 6:58 PM MST	Special Weather Statement	PSR		32 min
Aug 6, 7:54 PM MST	Dust Storm Advisory	PSR	Pinal	66 min

Nearby

Special Weather Statements in Arizona, 2021 Every special weather statement 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.