Flash Flood and Flood in Arizona, January 1 to 2, 2023

Name: Flash Flood and Flood in Arizona, January 1 to 2, 2023
Start: 2023-01-01T17:00
End: 2023-01-02T14:15
Location: Arizona

January 1 to 2, 2023 · NWS PSR · 2 events in 2 counties and zones

S. on the 1st, delivering moderate to locally heavy rainfall activity as well as embedded thunderstorm activity.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $40,000
Crop damage: None recorded
Events: 2

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.

What happened

The episode as NWS PSR wrote it up.

A strong low pressure system moved across the southwestern U.S. on the 1st, delivering moderate to locally heavy rainfall activity as well as embedded thunderstorm activity. Moisture values were well above normal for early January, with Precipitable water values ranged between 0.8-1. There was also some instability present, with Mixed Layer CAPE values between 100-500 J/KG, resulting in the formation of thunderstorms. The combination of the favorable moisture and instability parameters along with the strong dynamical forcing from the low pressure system resulted in very favorable conditions for a widespread swath of moderate to locally heavy rainfall to affect most of south-central Arizona. Rainfall amounts on average were under an inch across the lower deserts, however, across the higher terrain amounts were significantly higher, between 1-3.

What forecasters said that day

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 Jan 1, 1:30 PM MST, 3 hours 30 minutes earlier.

Area forecast discussion, Jan 1, 1:30 PM MST, 3 hours 30 minutes before

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In the hours before

Special weather statement, Jan 1, 3:25 PM MST, 1 hour 35 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
325 PM MST Sun Jan 1 2023

AZZ538>540-543-544-546-550-553-559-012315-
South Mountain/Ahwatukee AZ-Sonoran Desert Natl Monument AZ-
Scottsdale/Paradise Valley AZ-Buckeye/Avondale AZ-
Northwest Pinal County AZ-Tonopah Desert AZ-Gila Bend AZ-
Central Phoenix AZ-North Phoenix/Glendale AZ-
325 PM MST Sun Jan 1 2023

...Strong thunderstorms will impact portions of Maricopa and Pinal
Counties through 415 PM MST...

At 325 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from Cashion to 7 miles southwest of Gila Bend
Auxiliary Field. Movement was east at 25 mph.

HAZARD...Wind gusts up to 50 mph and half inch 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...
Phoenix, Avondale, Goodyear, Buckeye, Paradise Valley, Tolleson, Gila
Bend, Laveen, Cashion, Estrella, Litchfield Park, South Phoenix,
Cotton Center, Arizona State Fairgrounds, Liberty, South Mountain
Park, Camelback Mountain, Sky Harbor Airport, Estrella Mountain Park
and Estrella Mountain Ranch.

This includes the following highways...
AZ Interstate 10 between mile markers 123 and 151.
AZ Interstate 17 between mile markers 195 and 204.
AZ Interstate 8 between mile markers 104 and 133.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3275 11308 3350 11244 3352 11192 3283 11248
TIME...MOT...LOC 2225Z 259DEG 24KT 3344 11234 3282 11282

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Heil

Local storm report, Jan 1, 3:44 PM MST, 1 hour 16 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
344 PM MST SUN JAN 1 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0335 PM     HAIL             7 S CAVE CREEK          33.72N 111.98W
01/01/2023  E0.25 INCH       MARICOPA           AZ   PUBLIC

&&

INS

Special weather statement, Jan 1, 3:52 PM MST, 1 hour 8 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
352 PM MST Sun Jan 1 2023

AZZ541>549-556-557-012345-
Fountain Hills/East Mesa AZ-New River Mesa AZ-
Scottsdale/Paradise Valley AZ-Mazatzal Mountains AZ-Tonto Basin AZ-
Cave Creek/New River AZ-East Valley AZ-Central Phoenix AZ-
Deer Valley AZ-Rio Verde/Salt River AZ-North Phoenix/Glendale AZ-
352 PM MST Sun Jan 1 2023

...Strong thunderstorms will impact portions of Gila and Maricopa
Counties through 445 PM MST...

At 352 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from 11 miles southeast of Childs Power Plant to Sky
Harbor Airport. Movement was east at 30 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...
Phoenix, Mesa, Scottsdale, Tempe, Fountain Hills, Paradise Valley,
Sugarloaf Mountain, Sycamore Creek, Ballantine Trailhead, Round
Valley, Sunflower, Papago Park, Granite Reef Dam, Falcon Field
Airport, Salt River Indian Community, Usery Mountain Park, Downtown
Scottsdale, Goldfield Ranch, Scottsdale Airport and Camelback
Mountain.

This includes the following highways...
AZ Interstate 10 mile marker 149 and near mile marker 150.
AZ Route 87 between mile markers 176 and 229.
AZ Route 202 between mile markers 2 and 8, and between mile markers
12 and 23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3399 11142 3396 11139 3389 11126 3349 11147
      3342 11204 3400 11176 3400 11150 3401 11148
      3401 11143
TIME...MOT...LOC 2252Z 251DEG 28KT 3421 11159 3344 11199

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

Heil

Special weather statement, Jan 1, 4:12 PM MST, 48 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
412 PM MST Sun Jan 1 2023

AZZ552-556-558-560>563-020000-
Southeast Gila County AZ-Tonto Basin AZ-San Carlos AZ-
Dripping Springs AZ-Globe/Miami AZ-Superior AZ-
Pinal/Superstition Mountains AZ-
412 PM MST Sun Jan 1 2023

...Strong thunderstorms will impact portions of Gila,
Eastern Maricopa and Eastern Pinal Counties through 500 PM MST...

At 412 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from 9 miles north of Top-Of-The-World to 8 miles
northwest of Kearny. Movement was east at 35 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...
Globe, Superior, Miami, Top Of The World, Cutter, Central
Heights-Midland City, Top-Of-The-World, Claypool and Inspiration.

This includes the following highways...
US Highway 60 between mile markers 227 and 281.
AZ Route 70 between mile markers 253 and 267.
AZ Route 77 between mile markers 152 and 170.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3310 11085 3324 11095 3315 11109 3353 11112
      3367 11081 3366 11078 3370 11074 3378 11057
      3319 11051
TIME...MOT...LOC 2312Z 248DEG 29KT 3348 11105 3313 11103

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

Heil

Special weather statement, Jan 1, 4:16 PM MST, 44 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
416 PM MST Sun Jan 1 2023

AZZ539-553-554-559-020000-
Sonoran Desert Natl Monument AZ-Northwest Pinal County AZ-
Gila Bend AZ-West Pinal County AZ-
416 PM MST Sun Jan 1 2023

...Strong thunderstorms will impact portions of Maricopa and Pinal
Counties through 500 PM MST...

At 415 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from 9 miles north of Estrella to 6 miles southeast
of Gila Bend Auxiliary Field. Movement was east at 25 mph.

HAZARD...Wind gusts up to 50 mph and half inch 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...
Estrella, Freeman, Big Horn, Bosque, Estrella Sailport, Sonoran
National Monument and Mobile.

This includes the following highways...
AZ Interstate 8 between mile markers 121 and 142.
AZ Route 238 between mile markers 6 and 40.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3319 11203 3279 11233 3279 11277 3315 11244
TIME...MOT...LOC 2315Z 255DEG 20KT 3313 11237 3280 11268

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Heil

Special weather statement, Jan 1, 4:58 PM MST, 2 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
458 PM MST Sun Jan 1 2023

AZZ550-551-553-554-559-020045-
South Mountain/Ahwatukee AZ-Sonoran Desert Natl Monument AZ-
Northwest Pinal County AZ-Southeast Valley/Queen Creek AZ-
West Pinal County AZ-
458 PM MST Sun Jan 1 2023

...Strong thunderstorms will impact portions of Maricopa and Pinal
Counties through 545 PM MST...

At 458 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from near Estrella Sailport to 8 miles east of
Estrella to 9 miles west of Big Horn. Movement was east 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...
Sun Lakes, Maricopa, Estrella, Bapchule, Freeman, Big Horn, Estrella
Sailport, Ak-Chin Village, Mobile and Stanfield.

This includes the following highways...
AZ Interstate 10 between mile markers 168 and 173.
AZ Interstate 8 between mile markers 128 and 155.
AZ Route 238 between mile markers 16 and 44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3322 11184 3290 11193 3275 11225 3273 11271
      3298 11246 3322 11211
TIME...MOT...LOC 2358Z 250DEG 19KT 3313 11213 3300 11226 3282 11254

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

SDB

The radar

The Phoenix radar (KIWA), 33 km away, was scanning. The volume nearest the first event began at 00:00 UTC.

Open the radar archive at this moment

Event by event

1 flash flood, 1 flood. Local standard time, as filed.

Flash Flood, Pinal

When: January 1, 5:00 PM MST to 8:00 PM MST
Where: Pinal County, 2.18 mi NNE of Florence Jct to 1.85 mi NNE of Florence Jct
Cause: Heavy Rain
Reported by: Fire Department/Rescue
Coordinates: 33.299, -111.316

Floodwater out of Whitlow Canyon led to the closure of Silver King Rd. The employee from Queen Valley Fire Department said it was the highest flow he has ever seen. A Pinal County Flood Control streamflow gauge on Queen Creek at El Camino Viejo measured peak flow around 7 feet. No damages or injuries were reported.

Flood, Gila

When: January 2, 2:15 PM MST
Where: Gila County, 9.15 mi E of Sunflower to 9.11 mi E of Sunflower
Cause: Heavy Rain
Property damage: $40,000
Reported by: Local Official
Coordinates: 33.872, -111.311

A truck driver went around barricades trying to cross Tonto Creek along East Greenback Valley Road, but got stuck and had to be rescued by the Arizona Public Safety Ranger helicopter. The driver was unharmed. Timing based on the 911 call received from a Gila County Sheriff Officer. No injuries were reported.

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Arizona in 2023 Every state in 2023 This day in weather history Warnings in Arizona, January 2023

Sources

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: 1077662, 1077664.