Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 99, NWS Flagstaff, AZ

July 24, 2021Apache County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 24, 2021, 4:05 PM MST for Apache County, Arizona. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 24, 2021, 4:05 PM MST (23:05 UTC)
Expired: Jul 24, 2021, 7:15 PM MST
In force: 3 hr
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Apache County, AZ

The radar

The Flagstaff radar (KFSX), 168 km from the middle of the area, began a volume at 23:09 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.

What was reported inside it

Time	Report	Where	Remark
Jul 24, 7:10 PM MST	FLASH FLOOD	1 Ese Saint Johns, AZ	PUBLIC REPORTS FLASH FLOOD AT BRIDGE ON HIGHWAY 191 DUE TO LITTLE COLORADO RIVER. ROAD IMPASSABLE.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 11.1 hours before the alert went out and 239 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1053 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: -9 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

881 
WGUS55 KFGZ 242305
FFWFGZ
AZC001-250215-
/O.NEW.KFGZ.FF.W.0099.210724T2305Z-210725T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
405 PM MST Sat Jul 24 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  Apache County in northeastern Arizona...

* Until 715 PM MST.

* At 404 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain just south of St. Johns. Between 1 and 1.5 inches of 
  rain have fallen. Additional rainfall amounts of 0.75 to 1.25 
  inches are possible in the warned area. 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...
  St. Johns, Lyman Lake State Park, Concho and Lyman Lake.

This includes the following highways...
	Highway 180 between mile markers 358 and 368.
	State Route 61 between mile markers 368 and 381.
	Highway 191 161 near mile marker 316.
	Highway 180 191 between mile markers 371 and 385.

This includes the following streams and drainages...
  Carrizo Wash, Coyote Creek, Wildcat Creek, Oso Draw, Little 
  Colorado River, Lower Lyman Ditch, Concho Creek, Vigil Run, Big 
  Hollow Wash and Jarvis Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Flooding of washes and creeks will occur, some dirt roads will 
become muddy and impassable. Paved roads and underpasses could 
become flooded as well.

&&

LAT...LON 3451 10920 3432 10908 3427 10952 3445 10968
      3452 10953

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

$$

TPS

2 follow-up statements

499 
WGUS75 KFGZ 242338
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
438 PM MST Sat Jul 24 2021

AZC001-250215-
/O.CON.KFGZ.FF.W.0099.000000T0000Z-210725T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
438 PM MST Sat Jul 24 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 715 PM MST THIS 
EVENING FOR APACHE COUNTY...

At 432 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1.5 and 2.5 inches of rain have 
fallen. Additional rainfall amounts of 0.75 to 1.25 inches are 
possible in the warned area. Between 1.5 and 2.5 inches of rain has 
fallen in half an hour about 2 miles southeast of Concho. 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...
  St. Johns, Lyman Lake State Park, Concho and Lyman Lake.

This includes the following highways...
	Highway 180 between mile markers 358 and 368.
	State Route 61 between mile markers 368 and 381.
	Highway 191 161 near mile marker 316.
	 Highway 180 191 between mile markers 371 and 385.

This includes the following streams and drainages...
  Carrizo Wash, Coyote Creek, Wildcat Creek, Oso Draw, Little 
  Colorado River, Lower Lyman Ditch, Concho Creek, Vigil Run, Big 
  Hollow Wash and Jarvis Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Flooding of washes and creeks will occur, some dirt roads will 
become muddy and impassable. Paved roads and underpasses could 
become flooded as well.

&&

LAT...LON 3451 10920 3432 10908 3427 10952 3445 10968
      3452 10953

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

$$

McCollum

373 
WGUS75 KFGZ 250214
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
714 PM MST Sat Jul 24 2021

AZC001-250224-
/O.EXP.KFGZ.FF.W.0099.000000T0000Z-210725T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
714 PM MST Sat Jul 24 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 715 PM MST THIS EVENING FOR 
APACHE COUNTY...

The heavy rain has ended in the St. Johns area. Flooding is no 
longer expected to pose a threat. Please to heed road closures and 
don't drive through flooded roads.

A Flash Flood Watch remains in effect until 1200 AM MST Monday for 
portions of east central Arizona, north central Arizona, northeast 
Arizona and west central Arizona.

LAT...LON 3451 10920 3432 10908 3427 10952 3445 10968
      3452 10953

$$

McCollum

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 5:56 PM MST	Severe Thunderstorm Warning	FGZ	Apache	34 min
Jul 23, 6:00 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 23, 11:13 PM MST	Areal Flood Advisory	FGZ	Apache, Coconino, Gila, Navajo	5 hr
Jul 24, 7:22 AM MST	Areal Flood Advisory	FGZ	Apache, Coconino, Navajo	16 hr
Jul 24, 1:28 PM MST	Severe Thunderstorm Warning	FGZ	Apache	32 min
Jul 24, 1:56 PM MST	Severe Thunderstorm Warning	FGZ	Apache	34 min
Jul 24, 2:16 PM MST	Severe Thunderstorm Warning	FGZ	Apache	29 min
Jul 24, 2:43 PM MST	Severe Thunderstorm Warning	FGZ	Apache	32 min
Jul 24, 4:01 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	119 min
Jul 24, 4:18 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Apache, Navajo	3 hr
Jul 24, 4:20 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	25 min
Jul 24, 4:51 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	39 min
Jul 24, 4:58 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	32 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.