A shortwave trough rotating through the region led to steepening lapse rates and increasingly unstable conditions across central Arizona on the 16th. With abundant moisture and high CAPE values in place, the environment was favorable for the development of strong to severe thunderstorms.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PSR wrote it up.
A shortwave trough rotating through the region led to steepening lapse rates and increasingly unstable conditions across central Arizona on the 16th. With abundant moisture and high CAPE values in place, the environment was favorable for the development of strong to severe thunderstorms. Thunderstorms initially developed over the high terrain of eastern Arizona before racing toward the west/southwest into the lower deserts of south-central Arizona as a line of strong to severe thunderstorms. The main impacts associated with these thunderstorms occurred as they moved into the Phoenix metro, producing widespread damaging wind gusts. Multiple observations recorded wind gusts in excess of 60 mph with a few approaching 80 mph. Recently implemented damage threat categories for Severe Thunderstorm Warnings were put to the test with one destructive Severe Thunderstorm Warning being issued for 80 mph wind gusts for much of Phoenix. There were numerous reports of downed trees across the Valley as a result of the severe wind gusts. The strong winds also led to several reports of dense blowing dust in dust prone areas. Additionally, thunderstorms produced locally heavy rainfall that led to several instances of flash flooding. No injuries were reported.
The local office's own words before the first event, 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 the first event at Aug 16, 9:54 PM MST, 26 minutes earlier.
Area Forecast Discussion National Weather Service Phoenix AZ 954 PM MST Mon Aug 16 2021 .UPDATE... Updated 06Z aviation discussion and Flash Flood Watch for south central Arizona extended until 5 AM MST Tuesday. && .SYNOPSIS... Active monsoon weather will persist over much of Arizona into the middle part of the week creating daily chances for showers and thunderstorms. The best chance of thunderstorms through midweek will be this afternoon and evening. The primary threats with any storms will be localized heavy rainfall that may cause flash flooding and strong winds. A steeper decrease in moisture starting Wednesday should reduce rain chances across the area as early as Wednesday afternoon, but especially by Thursday. Much drier conditions are then anticipated by the weekend with temperatures eventually warming back to normal readings. && .DISCUSSION... Convection is off to an earlier than normal start today with midday radar and METSAT imagery showing areas of developing thunderstorms from NE of Tucson to the White Mountains/W NM and along the Rim NE of Phoenix. The storms SE-E of Phoenix and W- Cent NM formed along a positively tilted H3 trough axis aloft while the Rim storms were being triggered by a series of vort max disturbances grouped near a weak H5 E-W trough and thermal/cold trough embedded in the northerly flow over N AZ-NW NM. The anomalously moist airmass remains in place across the region today to complement the aforementioned triggers. The UL high has not moved much and is centered over Cent-CA at H5 with moist NE flow aloft and Nrly flow to the N. The latest ACARs mean soundings maintained elevated PW of 1.91" owing to a moist column from the BL through mid levels/H5. Also H7-H5 steering/flow remained NEerly. Also, MU CAPE had jumped up to 2,381 j/kg with modest CIN. Fairly decent chances for Monsoon storm activity will persist through Wednesday for Phoenix and the deserts. However the very best chance of thunderstorms, including an SPC Day 1 slight risk of severe convection, through Wed will occur early evening when NBM PPI/POPs spike up to 70%. Models agree on the area of disturbances to N-NE of the area to shift SWrd into S-Cent AZ including Phoenix and the lower deserts this afternoon and evening. As a result An organized area of storms is expected to fire along the rim with scattered to possibly/occasionally numerous storms descending through Phoenix and the lower deserts this evening and tonight. These storms will be capable of producing strong winds, heavy rainfall, and localized flash flooding, and hail as potential threats. The latest HREF continues to call for a >=70% chance of 35 mph wind gusts this evening in and around Phoenix and a >=10-20% chance of locally severe wind gusts of 60-75 mph. The latest HREF probability of 3-hr QPF >1" for this evening has increased to >=50% with WPC Day 1 ERO in the slight range for Phoenix and the deserts. This generally puts the risk of rainfall exceeding flash flood guidance at 10-20%. In preparation for this system the Flash Flood Watch for S-Cent AZ continues through 2 AM MST on Monday night. Although there remains 40-50% chance for lingering scattered showers and storms to last until dawn for Phoenix and the deserts. The HREF members are in good agreement on the timing of scattered thunderstorms in the early evening for Phoenix and the lower deserts. Although the FV3 is a slight outlier with a bit larger coverage for storms even though the other members already have pretty good coverage. The shortwave trough should mostly exit east of the region on Tuesday with the flow aloft weakening over the area. Guidance mostly points toward only modest storm chances during the day Tuesday, mostly focused over the high terrain. Can't rule out some of the high terrain storms making their way into the lower deserts, but the steering flow will be quite weak and shifting out of the west later in the day. Chances for showers and isolated storms should then increase Tuesday night into Wednesday morning from Phoenix and areas to the east of Phoenix as a unseasonably strong trough digs southeastward into the Great Basin and a fairly strong vort max tracks northward into southern Arizona later on Wednesday. Increasing difluent flow aloft should provide some broad scale ascent, possibly combining with potential vorticity from the incoming vort max sometime on Wednesday. Overall, the majority of the EPS and GEFS members support an area of rain developing across southern into central Arizona sometime Tuesday night into Wednesday morning, though instability will be fairly limited and elevated. Forecast PWATs of 1.6-1.9" would support some heavy rainfall, so an extension of the current Flash Flood Watch may be needed. Drier air aloft will begin working into the area from the west southwest later in the day Wednesday, but chances for showers and storms are likely to continue through Wednesday evening across eastern Arizona. The drier air should really be noticeable starting Thursday with PWATs lowering to around 1.25", which should completely end rain chances across the lower deserts. May see a few isolated showers and storms across the high terrain on Thursday, but NBM PoPs are only 15-25%. Ensembles then support continued dry westerly flow aloft through the upcoming weekend, likely even ending rain chances over most of the high terrain. Temperatures will also begin to warm later this week, but we may not see highs back to normal readings until maybe the weekend. && .AVIATION...Updated at 0454Z. South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: Thunderstorms impacting the Phoenix terminals over the next few hours will cause strong to severe winds, heavy rain, frequent lightning, and possibly blowing dust. A line of storms currently moving into eastern Maricopa County will cause northeast 25-35 knot outflows, with a 10-20% chance for winds to exceed 50 knots within thunderstorms at any terminal. Very isolated 60-70 knot gusts will be possible as well, with a Severe Thunderstorm Watch in effect until 07Z. The outflow should move into the East Valley including KIWA by 0515Z, KPHX by 0545Z, and clear the West Valley by 0615-0630Z. Thunderstorms should generally end by 08Z, with showers possible through 10Z. Light and variable winds are expected overnight once the shower activity ends, with perhaps a brief 1-2 hour period of southerly or southwest winds behind any organized lines of storms. Otherwise, winds will eventually settle upon easterlies at 5-10 knots late in the overnight hours before veering to westerly between 19-21Z with a brief period of southerly winds for a couple hours ahead of that switch. Another round of showers and thunderstorms will be possible again tomorrow evening or during the overnight hours into Wednesday morning, but the evolution of tonight's convection or lack thereof will strongly affect our storm chances tomorrow. Thus, for now we have not included any convection in the extended TAF for KPHX and will reevaluate for the next package. Ceilings will generally remain above 6-8 kft aside from brief decreases to 4-5 kft within thunderstorms. Southeast California/Southwest Arizona including KIPL and KBLH: Gusty winds this evening and again on Tuesday afternoon will be the main aviation impacts through the TAF period. In addition, isolated to scattered thunderstorms capable of producing blowing dust and strong to severe winds will be possible from 07-09Z over La Paz and Yuma Counties, but should eventually dissipate before crossing the Colorado River into southeast California. At KBLH, winds will generally favor a southerly component with speeds around 10-15 knots aside from gusts up to 20 knots tonight and 25-30 knots on Tuesday afternoon. Winds at KIPL will have more southeast headings, with gusts up to 25 knots expected. FEW-SCT cloud decks will stay above 10-15 kft aside from any thunderstorms in southwest Arizona overnight tonight. && .FIRE WEATHER... Wednesday through Sunday: The threat for showers and thunderstorms will continue through Wednesday before a drying trend sets in late in the week with dwindling chances for wetting rains on Thursday and likely little if any rain chances by Friday. Minimum humidities mostly between 30-45% on Wednesday will gradually lower to 15-30% late in the period. Temperatures will remain below normal across much of Arizona through the period, while the western deserts see near normal readings. && .SPOTTER INFORMATION STATEMENT... Spotters should follow standard reporting procedures. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Flash Flood Watch until 5 AM MST Tuesday for AZZ534-537>563. CA...None. && DISCUSSION...Sawtelle/Kuhlman AVIATION...Hopper FIRE WEATHER...Kuhlman
Special Weather Statement
National Weather Service Phoenix AZ
607 PM MST Mon Aug 16 2021
AZZ558-560-562-563-170145-
Southeast Gila County AZ-San Carlos AZ-Globe/Miami AZ-
Pinal/Superstition Mountains AZ-
607 PM MST Mon Aug 16 2021
...A strong thunderstorm will impact portions of Gila and Pinal
Counties through 645 PM MST...
At 607 PM MST, Doppler radar was tracking a strong thunderstorm near
Globe, moving south at 10 mph.
HAZARD...Winds in excess of 40 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.
Locations impacted include...
Globe, Miami, Cutter, Central Heights-Midland City, Claypool and
Inspiration.
This includes the following highways...
US Highway 60 between mile markers 239 and 255.
AZ Route 70 between mile markers 253 and 263.
AZ Route 77 between mile markers 159 and 170.
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.
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
A Severe Thunderstorm Watch remains in effect until midnight MST for
southeastern and east central Arizona.
&&
LAT...LON 3347 11089 3340 11055 3325 11061 3321 11082
3332 11097
TIME...MOT...LOC 0107Z 009DEG 7KT 3334 11080
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
ADSpecial Weather Statement
National Weather Service Phoenix AZ
637 PM MST Mon Aug 16 2021
AZZ552-558-561-562-170230-
Dripping Springs AZ-Globe/Miami AZ-Superior AZ-
Pinal/Superstition Mountains AZ-
637 PM MST Mon Aug 16 2021
...A strong thunderstorm will impact portions of Gila and Pinal
Counties through 730 PM MST...
At 637 PM MST, Doppler radar was tracking a strong thunderstorm near
Top-Of-The-World, or 7 miles east of Superior, moving south at 20
mph.
HAZARD...Winds in excess of 40 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.
Locations impacted include...
Superior, Miami and Top-Of-The-World.
This includes the following highways...
US Highway 60 between mile markers 227 and 242.
AZ Route 77 between mile markers 152 and 157.
AZ Route 177 between mile markers 159 and 167.
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.
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
A Severe Thunderstorm Watch remains in effect until midnight MST for
southeastern and east central Arizona.
&&
LAT...LON 3309 11085 3324 11094 3324 11097 3317 11105
3314 11111 3333 11110 3339 11095 3339 11088
3338 11086 3310 11077
TIME...MOT...LOC 0137Z 345DEG 18KT 3330 11098
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
ADSpecial Weather Statement
National Weather Service Phoenix AZ
824 PM MST Mon Aug 16 2021
AZZ559-170415-
Sonoran Desert Natl Monument AZ-
824 PM MST Mon Aug 16 2021
...A strong thunderstorm will impact portions of Maricopa County
through 915 PM MST...
At 824 PM MST, Doppler radar was tracking a strong thunderstorm near
Kaka, or 27 miles east of Ajo. This storm was nearly stationary.
HAZARD...Winds in excess of 40 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.
Locations impacted include...
Kaka.
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.
A Severe Thunderstorm Watch remains in effect until midnight MST for
south central Arizona.
&&
LAT...LON 3261 11257 3261 11234 3251 11229 3251 11253
TIME...MOT...LOC 0324Z 074DEG 2KT 3251 11242
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
ADSpecial Weather Statement
National Weather Service Phoenix AZ
853 PM MST Mon Aug 16 2021
AZZ556-558-562-563-170445-
Southeast Gila County AZ-Tonto Basin AZ-Globe/Miami AZ-
Pinal/Superstition Mountains AZ-
853 PM MST Mon Aug 16 2021
...A strong thunderstorm will impact portions of Gila, Maricopa and
Pinal Counties through 945 PM MST...
At 852 PM MST, Doppler radar was tracking a strong thunderstorm 12
miles north of Claypool, or 14 miles north of Globe, moving southwest
at 25 mph.
HAZARD...Winds in excess of 40 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.
Locations impacted include...
Globe, Miami, Central Heights-Midland City, Claypool, Roosevelt
Estates and Inspiration.
This includes the following highways...
US Highway 60 between mile markers 240 and 252, and between mile
markers 255 and 275.
AZ Route 188 between mile markers 214 and 240.
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.
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
A Severe Thunderstorm Watch remains in effect until midnight MST for
south central, southeastern and east central Arizona.
&&
LAT...LON 3333 11084 3341 11103 3374 11113 3376 11099
3364 11092 3368 11084 3366 11078 3375 11071
3358 11054
TIME...MOT...LOC 0352Z 046DEG 23KT 3361 11076
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
ADSpecial Weather Statement
National Weather Service Phoenix AZ
908 PM MST Mon Aug 16 2021
AZZ547-556>558-563-170500-
Southeast Gila County AZ-Mazatzal Mountains AZ-Tonto Basin AZ-
Rio Verde/Salt River AZ-Pinal/Superstition Mountains AZ-
908 PM MST Mon Aug 16 2021
...A strong thunderstorm will impact portions of Gila and Maricopa
Counties through 1000 PM MST...
At 908 PM MST, Doppler radar was tracking a strong thunderstorm 11
miles northeast of Roosevelt, moving southwest at 15 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.
Locations impacted include...
Roosevelt, Roosevelt Dam, Tonto National Monument and Roosevelt
Estates.
This includes AZ Route 188 between mile markers 227 and 253.
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.
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
A Severe Thunderstorm Watch remains in effect until midnight MST for
south central and east central Arizona.
&&
LAT...LON 3379 11113 3376 11099 3364 11092 3368 11083
3358 11088 3358 11090 3355 11090 3345 11097
3353 11113 3370 11131 3383 11119
TIME...MOT...LOC 0408Z 029DEG 12KT 3378 11098
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH
ADSpecial Weather Statement
National Weather Service Phoenix AZ
1001 PM MST Mon Aug 16 2021
AZZ541>553-555-557-558-170545-
Fountain Hills/East Mesa AZ-Mazatzal Mountains AZ-
Cave Creek/New River AZ-Northwest Pinal County AZ-East Valley AZ-
Southeast Valley/Queen Creek AZ-Apache Junction/Gold Canyon AZ-
Superior AZ-Rio Verde/Salt River AZ-Pinal/Superstition Mountains AZ-
North Phoenix/Glendale AZ-South Mountain/Ahwatukee AZ-
New River Mesa AZ-Scottsdale/Paradise Valley AZ-Central Phoenix AZ-
Deer Valley AZ-
1001 PM MST Mon Aug 16 2021
...Strong thunderstorms will impact portions of Maricopa and Pinal
Counties through 1045 PM MST...
At 1001 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from near Sugarloaf Mountain to Salt River Tubing
Recreation Area to Goldfield to 6 miles north of Queen Valley.
Movement was southwest at 35 mph.
HAZARD...Wind gusts of 50 to 55 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Phoenix, Mesa, Chandler, Scottsdale, Gilbert, Tempe, Apache Junction,
Florence, Fountain Hills, Paradise Valley, Superior, East Mesa, Gold
Canyon, Sugarloaf Mountain, Sun Lakes, Ballantine Trailhead, Queen
Creek, Cave Creek, Carefree and Tempe Marketplace.
This includes the following highways...
AZ Interstate 10 between mile markers 153 and 166.
US Highway 60 between mile markers 173 and 230.
AZ Route 87 between mile markers 147 and 210.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
A Severe Thunderstorm Watch remains in effect until midnight MST for
south central and southeastern Arizona.
&&
LAT...LON 3378 11150 3362 11138 3323 11097 3300 11130
3307 11172 3329 11201 3392 11195
TIME...MOT...LOC 0501Z 050DEG 30KT 3366 11158 3354 11156 3347 11150
3340 11131
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH
SDBThe Phoenix radar (KIWA), 28 km away, was scanning. The volume nearest the first event began at 05:19 UTC.
23 thunderstorm wind, 7 flash flood, 2 dust storm, 1 lightning, 1 hail. Local standard time, as filed.
A mature lemon tree along with multiple smaller trees with trunks approximately 8-10 inches in diameter were uprooted or broken. A saguaro was also pulled out of the ground. Timing was estimated using radar. No injuries were reported.
Heavy rainfall over the Salt Fire burn area led to enhanced runoff that resulted in flash flooding. The Arizona Department of Transportation reported closures along SR 188 north of Globe/Claypool due to flooding. Timing was estimated using a nearby USGS stream gage along Pinal Creek at Inspiration Dam, which rose over 3 feet beginning at 2145MST and crested at 4.47 feet near midnight. No damage or injuries were reported.
The SRP Quail mesonet station recorded a 73 mph gust.
Photos on social media show a charred pickup truck after catching on fire from being struck by lightning in a neighborhood near Ocotillo Road and Schnepf Road. No injuries were reported. Timing was estimated using radar.
A large tree approximately 4 feet in diameter was uprooted near Oasis Lane and Hunt Highway. Additional large trees were reported down in a nearby subdivision. Reduced visibility was also reported due to blowing dust. Timing was estimated using radar. No injuries were reported.
Multiple trees were reported down along Hunt Highway between Gary Road and Bella Vista Road. A fence was destroyed by a downed tree near Hunt Highway and Gantzel Road. No injuries were reported. Multiple trees were also reported to be uprooted along Charbray Drive between between Empire Boulevard and Skyline Drive. Timing was estimated using radar.
A large uprooted tree was reported to have caused damage to a brick wall and a sprinkler system at a home near Cactus Road and 101st Street. No injuries were reported.
Helicopter footage from a local TV station showed a large uprooted tree down on a home near Scottsdale Road and Chaparral Road. Footage also showed another large tree down at a nearby apartment complex, resulting in damage to the pool area and to one of the apartment buildings. Approximately 1 mile to the northeast, a large tree 2 feet in diameter was reported to have snapped in half along 82nd Street across from Saguaro High School. No injuries were reported. Timing was estimated using radar.
The Phoenix Sky Harbor ASOS recorded a 69 mph gust.
A 68 mph gust was recorded by a trained weather spotter using a handheld anemometer near Baseline Road and Rural Road.
A trained weather spotter recorded a 59 mph gust on a home weather station.
Photos on social media showed multiple trees uprooted along Cooper Road between Queen Creek Road and Ocotillo Road. No injuries were reported.
Photos on social media showed a large tree down on power lines near Lower Buckeye Road between 67th Avenue and 75th Avenue. Timing of 60-65 mph winds was estimated using radar. No injuries were reported.
Photos on social media showed downed power poles near 44th Street and Indian School Road. Additional photos showed a couple of snapped palm trees down in the same area causing severe damage to a vehicle as well as to the the gate of a driveway. No injuries were reported.
Videos on social media showed multiple trees down along Pecos Road between McQueen Road and Cooper Road in Chandler. Videos also showed a large tree in this area blocking a roadway requiring a large pickup truck to remove it. No injuries were reported.
Photos on social media showed a large uprooted tree along Alma School Road between Ray Road and Chandler Boulevard, causing damage to a block wall along with knocking down a light pole. No injuries were reported.
A photo on social media showed a large uprooted tree down on some power lines near 15th Avenue and Glendale Avenue. No injuries were reported.
The SRP Randolph mesonet station near Coolidge recorded a 64 mph gust.
A social media photo showed a large uprooted tree down on a carport at an apartment complex. No injuries or damaged cars were reported. Timing was estimated using radar.
Photos on social media showed a large tree approximately 40-50 feet tall snapped in half near 35th Avenue and Peoria Avenue. No injuries were reported.
A weather station located at the Gila River Valley Lookout on South Mountain measured a 75.6 mph gust.
A downed power pole was reported near Ellsworth Road and Brown Road in Mesa. No injuries were reported.
The Casa Grande Municipal Airport AWOS (KCGZ) recorded a 58 mph gust.
An Arizona Department of Transportation webcam near Highway 347 and Cement Plant Road showed dense blowing dust estimated to be reducing visibilities below 1/4 mile. No accidents or injuries were reported.
An Arizona Department of Transportation webcam on the Loop 303 near Bethany Home Road showed near zero visibility due to dense blowing dust. No accidents or injuries were reported.
Sossaman Road and Via Del Jardin was closed at Sonoqui Wash due to flooding. A nearby Maricopa County Flood Control District stream gage near Hawes Road recorded flow in the wash climbing above alarm stage at around 2340MST. Flow in the wash continued to increase during the early morning hours on the 17th before cresting above bank full at 7.10 feet and 2237 CFS at 0010MST. Timing was estimated using the stream gage. No damage or injuries were reported.
Several downed trees were reported within neighborhoods surrounding Estrella Parkway and Yuma Road. The largest downed tree was approximately 40 feet tall. No injuries were reported.
The Maricopa County Flood Control District Mobile AZ ALERT mesonet station recorded a 60 mph gust.
The Arizona Department of Transportation reported that SR 87 was closed due to flooding near Arizona Boulevard. No damage or injuries were reported.
Heavy rain flooded the underpass of I-17 at Greenway Road with at least one driver becoming stuck. No injuries were reported.
Maricopa County Flood Control District stream gage ACDC at 43rd Avenue exceeded alarm stage resulting in downstream impacts at Thunderbird Paseo Park. Timing was estimated from when the gage reach alarm stage and time to travel downstream. No damage or injuries were reported.
Video on social media showed water rapidly flowing across 12th Street near the Torre Blanca community making the street impassable. No damage or injuries were reported.
The City of Goodyear reported that Citrus Road was closed between I-10 and Van Buren Street as well as Yuma Road and Durango Street due to flooding. No damage or injuries were reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2021Every state in 2021This day in weather historyWarnings in Arizona, August 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 983666, 983653, 983667, 983859, 983826, 983668, 983669, 983864, 983860, 983670, 983671, 983672, 983675, 983676, 983686, 983677, 983861, 983678, 983679, 983862, 983863, 983858, 983681, 983683, 983735, 983736, 983825, 983733, 983734, 983865, 983866, 983867, 983868, 983869.