Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Phoenix, AZ

August 14, 2021

NWS Phoenix, AZ issued this special weather statement at Aug 14, 2021, 7:17 PM MST. It was in force for 43 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 14, 2021, 7:17 PM MST (02:17 UTC)
Expired: Aug 14, 2021, 8:00 PM MST
In force: 43 min
Issued by: NWS Phoenix, AZ
Hail: 0.25 in
Wind: 50

The radar

The Phoenix radar (KIWA), 116 km from the middle of the area, began a volume at 02:17 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, 2.3 hours before the alert went out and 110 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: 1092 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 1640 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 106 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 14, 4:04 PM MST, 3 hours 13 minutes earlier.

Area forecast discussion, Aug 14, 4:04 PM MST, 3 hours 13 minutes before

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In the hours before

Special weather statement, Aug 14, 6:17 PM MST, 1 hour before

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  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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Special weather statement, Aug 14, 6:33 PM MST, 44 minutes before

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Special weather statement, Aug 14, 6:36 PM MST, 41 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
636 PM MST Sat Aug 14 2021

AZZ559-150215-
Sonoran Desert Natl Monument AZ-
636 PM MST Sat Aug 14 2021

...A strong thunderstorm will impact portions of Maricopa County
through 715 PM MST...

At 635 PM MST, Doppler radar was tracking a strong thunderstorm 11
miles west of Kaka, or 23 miles northeast of Ajo, moving northwest at
10 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of Maricopa County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

&&

LAT...LON 3264 11249 3251 11234 3250 11242 3251 11264
      3252 11263
TIME...MOT...LOC 0135Z 116DEG 9KT 3254 11251

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

DH

Special weather statement, Aug 14, 6:45 PM MST, 32 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
645 PM MST Sat Aug 14 2021

AZZ537-540-543-544-548-550-551-553-554-559-150230-
South Mountain/Ahwatukee AZ-Sonoran Desert Natl Monument AZ-
Buckeye/Avondale AZ-Northwest Pinal County AZ-East Valley AZ-
Southeast Valley/Queen Creek AZ-Central Phoenix AZ-
Northwest Valley AZ-West Pinal County AZ-North Phoenix/Glendale AZ-
645 PM MST Sat Aug 14 2021

...A strong thunderstorm will impact portions of Maricopa and Pinal
Counties through 730 PM MST...

At 645 PM MST, Doppler radar was tracking a strong thunderstorm over
Arizona State University, or over Tempe, moving west at 35 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

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

Locations impacted include...
Phoenix, Chandler, Glendale, Tempe, Avondale, Goodyear, El Mirage,
Tolleson, Youngtown, Laveen, Cashion, Sun City, Litchfield Park,
North Mountain Park, South Phoenix, Arizona State Fairgrounds, South
Mountain Park, Downtown Peoria, Downtown Glendale and Sky Harbor
Airport.

This includes the following highways...
AZ Interstate 10 between mile markers 127 and 164.
AZ Interstate 17 between mile markers 195 and 211.
AZ Route 51 between mile markers 1 and 7.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

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 3363 11208 3330 11186 3311 11220 3356 11245
TIME...MOT...LOC 0145Z 072DEG 29KT 3342 11194

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

DH

Special weather statement, Aug 14, 6:53 PM MST, 24 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
653 PM MST Sat Aug 14 2021

AZZ541-542-544-545-547-150245-
New River Mesa AZ-Cave Creek/New River AZ-Deer Valley AZ-
Rio Verde/Salt River AZ-North Phoenix/Glendale AZ-
653 PM MST Sat Aug 14 2021

...A strong thunderstorm will impact portions of Maricopa County
through 745 PM MST...

At 653 PM MST, Doppler radar was tracking a strong thunderstorm over
Carefree, or 9 miles north of Scottsdale, moving west at 20 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

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

Locations impacted include...
Phoenix, Scottsdale, New River, Cave Creek, Carefree, Deer Valley
Airport, McDowell Mountain Park, Desert Mountain, Desert Ridge
Marketplace, Camp Creek, Horseshoe Reservoir, Anthem and Seven
Springs.

This includes the following highways...
AZ Interstate 17 between mile markers 212 and 241.
AZ Route 51 between mile markers 14 and 15.
AZ Route 101 between mile markers 21 and 36.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3402 11194 3402 11186 3401 11185 3400 11175
      3400 11163 3368 11173 3364 11195 3366 11198
      3364 11199 3361 11216 3405 11215
TIME...MOT...LOC 0153Z 084DEG 18KT 3383 11188

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

DH

Special weather statement, Aug 14, 7:17 PM MST, 0 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
717 PM MST Sat Aug 14 2021

AZZ559-150300-
Sonoran Desert Natl Monument AZ-
717 PM MST Sat Aug 14 2021

...A strong thunderstorm will impact portions of Maricopa County
through 800 PM MST...

At 717 PM MST, Doppler radar was tracking a strong thunderstorm 14
miles north of Hickiwan, or 20 miles northeast of Ajo, moving
northwest at 10 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of Maricopa County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

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 3266 11270 3264 11245 3251 11244 3251 11273
TIME...MOT...LOC 0217Z 122DEG 7KT 3255 11258

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

DH

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 14, 5:26 PM MST	Special Weather Statement	PSR		49 min
Aug 14, 5:46 PM MST	Special Weather Statement	PSR		44 min
Aug 14, 5:51 PM MST	Severe Thunderstorm Warning	PSR	Gila, Maricopa	24 min
Aug 14, 6:17 PM MST	Special Weather Statement	PSR		43 min
Aug 14, 6:22 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	38 min
Aug 14, 6:33 PM MST	Special Weather Statement	PSR		42 min
Aug 14, 6:36 PM MST	Special Weather Statement	PSR		39 min
Aug 14, 6:45 PM MST	Special Weather Statement	PSR	Maricopa	45 min
Aug 14, 6:53 PM MST	Special Weather Statement	PSR		52 min
Aug 14, 7:19 PM MST	Special Weather Statement	PSR		41 min
Aug 14, 11:13 PM MST	Special Weather Statement	PSR	La Paz	47 min
Aug 14, 11:17 PM MST	Special Weather Statement	PSR	La Paz	43 min
Aug 14, 11:26 PM MST	Special Weather Statement	PSR		64 min
Aug 15, 12:55 AM MST	Special Weather Statement	PSR		65 min
Aug 15, 4:42 AM MST	Areal Flood Advisory	PSR	Maricopa, Yuma	6 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.