Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Phoenix, AZ

August 10, 2021Maricopa County, Arizona

NWS Phoenix, AZ issued this special weather statement at Aug 10, 2021, 1:40 AM MST for Maricopa County, Arizona. It was in force for 50 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 10, 2021, 1:40 AM MST (08:40 UTC)
Expired: Aug 10, 2021, 2:30 AM MST
In force: 50 min
Issued by: NWS Phoenix, AZ
Hail: 0.00 in
Wind: 40

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 51 km from the middle of the area, began a volume at 08:42 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, 8.7 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: 413 J/kg
Mixed-layer CIN: -229 J/kg
Mixed-layer LCL: 1911 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 88 m²/s²
0-3 km storm-relative helicity: 136 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Phoenix, AZ wrote its last area forecast discussion before this special weather statement went out at Aug 9, 11:20 PM MST, 2 hours 20 minutes earlier.

Area forecast discussion, Aug 9, 11:20 PM MST, 2 hours 20 minutes before

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In the hours before

Special weather statement, Aug 9, 10:11 PM MST, 3 hours 29 minutes before

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Special weather statement, Aug 10, 1:40 AM MST, 0 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
140 AM MST Tue Aug 10 2021

AZZ537-538-540-543-544-548-550-551-553-554-559-100930-
South Mountain/Ahwatukee AZ-Sonoran Desert Natl Monument AZ-
Buckeye/Avondale AZ-Northwest Pinal County AZ-East Valley AZ-
Tonopah Desert AZ-Southeast Valley/Queen Creek AZ-Central Phoenix AZ-
Northwest Valley AZ-West Pinal County AZ-North Phoenix/Glendale AZ-
140 AM MST Tue Aug 10 2021

...A strong thunderstorm will impact portions of Maricopa and Pinal
Counties through 230 AM MST...

At 139 AM MST, Doppler radar was tracking an area of strong
thunderstorms 8 miles north of Estrella Sailport, or 14 miles west
of Sun Lakes, moving north at 5 mph.

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...
Phoenix, Chandler, Glendale, Tempe, Surprise, Avondale, Goodyear,
Buckeye, El Mirage, Tolleson, Sun Lakes, Waddell, Laveen, Cashion,
Litchfield Park, Palo Verde, White Tank Mountain Park, South Phoenix,
Liberty and South Mountain Park.

This includes the following highways...
AZ Interstate 10 between mile markers 109 and 141, and between mile
markers 157 and 172.
AZ Interstate 17 between mile markers 198 and 199.
AZ Route 87 between mile markers 157 and 166.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3315 11199 3309 11219 3328 11237 3327 11260
      3347 11271 3362 11258 3362 11235 3347 11228
      3348 11218 3339 11201 3331 11184 3318 11173
TIME...MOT...LOC 0839Z 159DEG 5KT 3320 11213

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

JS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 5:24 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Aug 9, 5:44 PM MST	Special Weather Statement	PSR	La Paz	46 min
Aug 9, 6:22 PM MST	Special Weather Statement	PSR		38 min
Aug 9, 10:11 PM MST	Special Weather Statement	PSR	Gila	34 min
Aug 9, 10:40 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Aug 9, 11:51 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	8 hr
Aug 10, 1:54 AM MST	Special Weather Statement	PSR	Maricopa	51 min
Aug 10, 2:15 AM MST	Special Weather Statement	PSR	Maricopa	45 min
Aug 10, 2:23 AM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	2 hr
Aug 10, 4:27 AM MST	Special Weather Statement	PSR	La Paz	48 min
Aug 10, 5:07 AM MST	Special Weather Statement	PSR	La Paz	53 min
Aug 10, 5:09 AM MST	Areal Flood Advisory	PSR	La Paz	2 hr
Aug 10, 5:52 AM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	5 hr
Aug 10, 6:21 AM MST	Special Weather Statement	PSR	La Paz	39 min
Aug 10, 7:39 AM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	3 hr
Aug 10, 8:00 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	3 hr
Aug 10, 8:06 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Aug 10, 8:30 AM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa, Pinal	7 hr
Aug 10, 9:54 AM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Aug 10, 3:05 PM MST	Areal Flood Warning	PSR	Maricopa, Pinal	7 hr
Aug 10, 4:43 PM MST	Special Weather Statement	PSR		62 min
Aug 10, 4:44 PM MST	Special Weather Statement	PSR		61 min
Aug 10, 4:56 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	49 min
Aug 9, 5:06 PM MST	Areal Flood Advisory	PSR	Riverside	3 hr
Aug 9, 6:09 PM MST	Areal Flood Advisory	PSR	Riverside, San Bernardino	115 min
Aug 10, 3:11 PM MST	Areal Flood Advisory	PSR	Riverside, San Bernardino	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.