Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 16, NWS Flagstaff, AZ

July 10, 2021Gila County, Navajo County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 10, 2021, 6:23 PM MST for Gila County, Navajo 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: Jul 10, 2021, 6:23 PM MST (01:23 UTC)
Expired: Jul 10, 2021, 9:30 PM MST
In force: 3 hr
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Gila County, AZ, Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 87 km from the middle of the area, began a volume at 01:22 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, 1.4 hours before the alert went out and 139 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: 965 J/kg
Mixed-layer CIN: -311 J/kg
Mixed-layer LCL: 3378 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 116 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

499 
WGUS55 KFGZ 110123
FFWFGZ
AZC007-017-110430-
/O.NEW.KFGZ.FF.W.0016.210711T0123Z-210711T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
623 PM MST Sat Jul 10 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  Gila County in east central Arizona...
  Navajo County in north central Arizona...

* Until 930 PM MST.

* At 622 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Life-threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life-threatening flash flooding of low-water
           crossings, creeks, normally dry washes and roads.

* Some locations that will experience flash flooding include...
  Fort Apache Reservation.

This includes the following streams and drainages...
  Canyon Creek, Oak Creek, Salt River, Spring Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for flooding even in locations not receiving rain. 
Normally dry washes, slot canyons and creeks can become raging 
killer currents in a matter of minutes, even from distant rainfall.

Get out of washes and creeks if you are camping or hiking! Flooding 
is occurring or imminent and will inundate area drainages.

&&

LAT...LON 3402 11069 3409 11069 3411 11063 3411 11060
      3403 11058 3400 11058 3396 11054 3392 11055
      3391 11057 3387 11056 3385 11056 3384 11057
      3383 11060 3394 11063 3396 11065 3398 11068

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

NL

2 follow-up statements

916 
WGUS75 KFGZ 110242
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
742 PM MST Sat Jul 10 2021

AZC007-017-110430-
/O.CON.KFGZ.FF.W.0016.000000T0000Z-210711T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Navajo AZ-
742 PM MST Sat Jul 10 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 930 PM MST THIS 
EVENING FOR GILA AND NAVAJO COUNTIES...

At 739 PM MST, heavy rainfall has ended in the area, but between 1.5 
and 2.5 inches of rain have fallen. Flash flooding is likely in some 
area drainages, with runoff ultimately flowing through the Salt 
River Draw.

HAZARD...Life-threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life-threatening flash flooding of low-water crossings,
         creeks, normally dry washes and roads.

Some locations that will experience flash flooding include...
  Fort Apache Reservation.

This includes the following streams and drainages...
  Canyon Creek, Oak Creek, Salt River, Spring Creek and Cibecue 
  Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for flooding even in locations not receiving rain. 
Normally dry washes, slot canyons and creeks can become raging 
killer currents in a matter of minutes, even from distant rainfall.

Get out of washes and creeks if you are camping or hiking! Flooding 
is occurring or imminent and will inundate area drainages.

&&

LAT...LON 3402 11069 3409 11069 3411 11063 3411 11060
      3403 11058 3400 11058 3396 11054 3392 11055
      3391 11057 3387 11056 3385 11056 3384 11057
      3383 11060 3394 11063 3396 11065 3398 11068

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

RR

967 
WGUS75 KFGZ 110420
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
920 PM MST Sat Jul 10 2021

AZC007-017-110430-
/O.EXP.KFGZ.FF.W.0016.000000T0000Z-210711T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Navajo AZ-
920 PM MST Sat Jul 10 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 930 PM MST THIS EVENING FOR 
GILA AND NAVAJO COUNTIES...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3402 11069 3409 11069 3411 11063 3411 11060
      3403 11058 3400 11058 3396 11054 3392 11055
      3391 11057 3387 11056 3385 11056 3384 11057
      3383 11060 3394 11063 3396 11065 3398 11068

$$

RR

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 5:09 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Gila, Yavapai	51 min
Jul 10, 5:16 PM MST	Severe Thunderstorm Warning	FGZ	Apache, Coconino, Gila, Navajo	44 min
Jul 10, 5:56 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Yavapai	49 min
Jul 10, 6:44 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Yavapai	35 min
Jul 11, 3:22 PM MST	Special Weather Statement	FGZ	Yavapai	23 min
Jul 11, 3:35 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	40 min
Jul 11, 3:49 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	41 min
Jul 11, 4:25 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	35 min
Jul 11, 4:46 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	29 min
Jul 11, 4:58 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	11 min

Nearby

Flash Flood Warnings in Arizona, 2021 Every 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.