Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 118, NWS Flagstaff, AZ

July 28, 2021Gila County, Navajo County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 28, 2021, 4:43 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 28, 2021, 4:43 PM MST (23:43 UTC)
Expired: Jul 28, 2021, 7:45 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), 134 km from the middle of the area, began a volume at 23:46 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, 11.7 hours before the alert went out and 188 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: 438 J/kg
Mixed-layer CIN: -225 J/kg
Mixed-layer LCL: 1861 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 39 m²/s²
0-3 km storm-relative helicity: 32 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

455 
WGUS55 KFGZ 282343
FFWFGZ
AZC007-017-290245-
/O.NEW.KFGZ.FF.W.0118.210728T2343Z-210729T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
443 PM MST Wed Jul 28 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 745 PM MST.

* At 440 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain in and west of Whiteriver. 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...
  Rainbow City, Whiteriver, Fort Apache, Seven Mile, Fort Apache 
  Reservation and Canyon Day.

This includes the following highways...
	State Route 73 between mile markers 333 and 346.

This includes the following streams and drainages...
  North Fork White River, White River, Diamond Creek, Amos Wash, 
  Bear Canyon, Deer Spring Creek and East Fork White River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3378 11004 3392 11008 3396 11006 3400 11004
      3400 10997 3393 10993 3384 10994 3378 10996
      3376 10999

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

$$

Peterson

2 follow-up statements

745 
WGUS75 KFGZ 290201
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
701 PM MST Wed Jul 28 2021

AZC007-017-290245-
/O.CON.KFGZ.FF.W.0118.000000T0000Z-210729T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Navajo AZ-
701 PM MST Wed Jul 28 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM MST THIS 
EVENING FOR GILA AND NAVAJO COUNTIES...

At 701 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain have ended in the Whiteriver area. Between 1.25 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...
  Rainbow City, Whiteriver, Fort Apache, Seven Mile, Fort Apache 
  Reservation and Canyon Day.

This includes the following highways...
	State Route 73 between mile markers 333 and 346.

This includes the following streams and drainages...
  North Fork White River, White River, Diamond Creek, Amos Wash, 
  Bear Canyon, Deer Spring Creek and East Fork White River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

In hilly or mountainous terrain, there are many low water crossings 
which will become dangerous in heavy rain. Do not attempt to cross 
flooded roads. Find an alternate route.

&&

LAT...LON 3378 11004 3392 11008 3396 11006 3400 11004
      3400 10997 3393 10993 3384 10994 3378 10996
      3376 10999

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

$$

TPS

046 
WGUS75 KFGZ 290237
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
737 PM MST Wed Jul 28 2021

AZC007-017-290247-
/O.EXP.KFGZ.FF.W.0118.000000T0000Z-210729T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Navajo AZ-
737 PM MST Wed Jul 28 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 745 PM MST THIS EVENING FOR 
GILA AND NAVAJO COUNTIES...

The heavy rain threat has ended in the Whiteriver area. Flooding is 
no longer expected to pose a threat. Please continue to heed 
remaining road closures.

LAT...LON 3378 11004 3392 11008 3396 11006 3400 11004
      3400 10997 3393 10993 3384 10994 3378 10996
      3376 10999

$$

TPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 27, 7:28 PM MST	Special Weather Statement	FGZ		32 min
Jul 27, 8:06 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 28, 11:46 AM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 28, 3:07 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 28, 3:35 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 28, 4:35 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	2 hr

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.