Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Phoenix, AZ

July 20, 2021

NWS Phoenix, AZ issued this special weather statement at Jul 20, 2021, 2:28 PM MST. It was in force for 32 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: Jul 20, 2021, 2:28 PM MST (21:28 UTC)
Expired: Jul 20, 2021, 3:00 PM MST
In force: 32 min
Issued by: NWS Phoenix, AZ

The radar

The Phoenix radar (KIWA), 53 km from the middle of the area, began a volume at 21:30 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 12:00Z, 9.5 hours before the alert went out and 63 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: 1057 J/kg
Mixed-layer CIN: -177 J/kg
Mixed-layer LCL: 1907 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 16 m²/s²
0-3 km storm-relative helicity: 32 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

046 
WWUS85 KPSR 202128
SPSPSR

Special Weather Statement
National Weather Service Phoenix AZ
228 PM MST Tue Jul 20 2021
 
AZZ547-556-557-202200-
Mazatzal Mountains AZ-Tonto Basin AZ-Rio Verde/Salt River AZ-
228 PM MST Tue Jul 20 2021

...SIGNIFICANT WEATHER ADVISORY FOR GILA AND MARICOPA COUNTIES UNTIL
300 PM MST...

At 228 PM MST, Doppler radar was tracking a strong thunderstorm near
Four Peaks, or 8 miles east of Sugarloaf Mountain, moving north at 15
mph.

Pea size hail and wind gusts of 50 to 55 mph will be possible with
this storm.

Locations impacted include...
Ballantine Trailhead, Four Peaks and Tonto Basin. 

This includes AZ Route 87 between mile markers 206 and 211.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3365 11130 3362 11141 3376 11158 3383 11130
TIME...MOT...LOC 2128Z 161DEG 12KT 3367 11139 

$$

JS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 19, 6:20 PM MST	Special Weather Statement	PSR	La Paz	40 min
Jul 19, 6:52 PM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz	2 hr
Jul 20, 1:33 PM MST	Special Weather Statement	PSR		42 min
Jul 20, 1:41 PM MST	Special Weather Statement	PSR		49 min
Jul 20, 2:02 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Jul 20, 2:17 PM MST	Special Weather Statement	PSR		43 min
Jul 20, 2:37 PM MST	Special Weather Statement	PSR		53 min
Jul 20, 2:43 PM MST	Special Weather Statement	PSR		47 min
Jul 20, 2:57 PM MST	Special Weather Statement	PSR		48 min
Jul 20, 3:05 PM MST	Special Weather Statement	PSR		40 min
Jul 20, 3:08 PM MST	Special Weather Statement	PSR		52 min
Jul 20, 3:20 PM MST	Special Weather Statement	PSR	La Paz	40 min
Jul 20, 3:32 PM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz, Maricopa	3 hr
Jul 20, 3:36 PM MST	Special Weather Statement	PSR		39 min
Jul 20, 3:47 PM MST	Special Weather Statement	PSR		43 min
Jul 20, 3:55 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	3 hr
Jul 20, 4:21 PM MST	Special Weather Statement	PSR		39 min
Jul 20, 4:23 PM MST	Special Weather Statement	PSR	La Paz	52 min
Jul 20, 4:30 PM MST	Special Weather Statement	PSR		45 min
Jul 20, 4:41 PM MST	Flash Flood Warning Considerable damage threat	PSR	La Paz	3 hr
Jul 20, 4:47 PM MST	Special Weather Statement	PSR	Gila	43 min
Jul 20, 4:53 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Jul 20, 4:57 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr

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.