Alert archive / Arizona / Flash Flood Warnings in 2021
Flash Flood Warning 235, NWS Phoenix, AZ
NWS Phoenix, AZ issued this flash flood warning at Aug 31, 2021, 4:55 PM MST for Gila County, Maricopa County, Arizona. It was in force for 3 hr. 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 31, 2021, 4:55 PM MST (23:55 UTC)
- Expired
- Aug 31, 2021, 7:42 PM MST
- In force
- 3 hr
- Issued by
- NWS Phoenix, AZ
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
Counties Gila County, AZ, Maricopa County, AZ
The radar
The Phoenix radar (KIWA), 51 km from the middle of the area, began a volume at 23:55 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, 11.9 hours before the alert went out and 71 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.
- Mixed-layer CAPE
- 243 J/kg
- Mixed-layer CIN
- -208 J/kg
- Mixed-layer LCL
- 1906 m above ground
- 0-6 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- -16 m²/s²
- 0-3 km storm-relative helicity
- 7 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
934
WGUS55 KPSR 312355
FFWPSR
AZC007-013-010800-
/O.NEW.KPSR.FF.W.0235.210831T2355Z-210901T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
455 PM MST Tue Aug 31 2021
The National Weather Service in Phoenix has issued a
* Flash Flood Warning for...
The Woodbury burn scar in...
Gila County in east central Arizona...
Maricopa County in south central Arizona...
* Until 100 AM MST Wednesday.
* At 455 PM MST, Doppler radar indicated thunderstorms producing
heavy rain over the Woodbury Burn Scar. Between 0.5 and 1.5 inches
of rain have fallen. Additional rainfall amounts of 0.5 to 1 inch
are possible in the warned area. Flash flooding is ongoing or
expected to begin shortly.
Excessive rainfall over the burn scar will result in debris flow
moving through the Woodbury. The debris flow can consist of rock,
mud, vegetation and other loose materials.
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding in and around the Woodbury
Burn Scar.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of areas in and around
the Woodbury Burn Scar.
* Some locations that will experience flash flooding include...
Apache Lake.
Crabtree Wash
This includes the following streams and drainages...
Ash Creek, Barranca Creek, Lewis and Pranty Creek, Salt River,
Reavis Creek, Pine Creek, Alder Creek, Bronco Creek and Burnt
Corral Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
This is a life threatening situation. Heavy rainfall will cause
extensive and severe flash flooding of creeks...streams...and
ditches in the Woodbury Burn Scar. Severe debris flows can also be
anticipated across roads. Roads and driveways may be washed away in
places. If you encounter flood waters...climb to safety.
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3364 11127 3363 11121 3359 11116 3355 11112
3350 11112 3349 11113 3348 11115 3348 11118
3348 11120 3350 11124 3351 11129 3356 11131
3359 11132 3362 11131
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Hirsch1 follow-up statement
399
WGUS75 KPSR 010242
FFSPSR
Flash Flood Statement
National Weather Service Phoenix AZ
742 PM MST Tue Aug 31 2021
AZC007-013-010252-
/O.CAN.KPSR.FF.W.0235.000000T0000Z-210901T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Maricopa AZ-
742 PM MST Tue Aug 31 2021
...FLASH FLOOD WARNING FOR THE WOODBURY BURN SCAR IS CANCELLED FOR
GILA AND MARICOPA COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
A Flash Flood Watch remains in effect until 500 AM MST Thursday for
portions of south central Arizona and southwest Arizona.
LAT...LON 3364 11127 3363 11121 3359 11116 3355 11112
3350 11112 3349 11113 3348 11115 3348 11118
3348 11120 3350 11124 3351 11129 3356 11131
3359 11132 3362 11131
$$
HirschThe office that day
Everything else NWS Phoenix, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 8:18 PM MST | Special Weather Statement | PSR | 27 min | |
| Aug 30, 9:06 PM MST | Flash Flood Warning | PSR | La Paz | 5 hr |
| Aug 30, 10:59 PM MST | Areal Flood Advisory | PSR | Maricopa, Pinal | 4 hr |
| Aug 30, 11:17 PM MST | Areal Flood Advisory | PSR | La Paz | 3 hr |
| Aug 31, 12:06 AM MST | Special Weather Statement | PSR | Maricopa | 39 min |
| Aug 31, 12:24 AM MST | Areal Flood Advisory | PSR | Maricopa | 3 hr |
| Aug 31, 12:50 AM MST | Flash Flood Warning | PSR | Maricopa | 4 hr |
| Aug 31, 2:55 AM MST | Areal Flood Advisory | PSR | Maricopa | 3 hr |
| Aug 31, 5:52 AM MST | Areal Flood Advisory | PSR | Maricopa | 3 hr |
| Aug 31, 12:39 PM MST | Special Weather Statement | PSR | 66 min | |
| Aug 31, 1:13 PM MST | Areal Flood Advisory | PSR | La Paz | 6 hr |
| Aug 31, 1:24 PM MST | Flash Flood Warning | PSR | La Paz | 13 hr |
| Aug 31, 1:35 PM MST | Special Weather Statement | PSR | 70 min |
Nearby
Flash Flood Warnings in Arizona, 2021Every flash flood warning 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.