Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 85, NWS Flagstaff, AZ

July 22, 2021Navajo County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 22, 2021, 8:06 PM MDT for 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 22, 2021, 8:06 PM MDT (02:06 UTC)
Expired: Jul 22, 2021, 11:00 PM MDT
In force: 3 hr
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 106 km from the middle of the area, began a volume at 02:08 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

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 2.1 hours before the alert went out and 116 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: 1033 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 1131 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: 6 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

893 
WGUS55 KFGZ 230206
FFWFGZ
AZC017-230500-
/O.NEW.KFGZ.FF.W.0085.210723T0206Z-210723T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
706 PM MST Thu Jul 22 2021

The National Weather Service in Flagstaff has issued a

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

* Until 1000 PM MST.

* At 706 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 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...
  Dilkon and Navajo Reservation.

This includes the following highways...
	State Route 87 between mile markers 369 and 381.

This includes the following streams and drainages...
  Tees Toh Wash, Little Colorado River and Coyote Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3550 11049 3538 11030 3515 11055 3525 11072
      3537 11067

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

$$

McCollum

4 follow-up statements

246 
WGUS75 KFGZ 230227
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
727 PM MST Thu Jul 22 2021

AZC017-230500-
/O.CON.KFGZ.FF.W.0085.000000T0000Z-210723T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Navajo AZ-
727 PM MST Thu Jul 22 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM MST THIS 
EVENING FOR NAVAJO COUNTY...

At 725 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain continued across the warned area. Between 1.5 and 2.5 inches of 
rain have fallen. Additional rainfall amounts of 0.5 to 1.5 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...
  Dilkon and areas west of Dilkon.

This includes the following highways...
	State Route 87 between mile markers 369 and 381.

This includes the following streams and drainages...
  Tees Toh Wash and Coyote Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3550 11049 3538 11030 3515 11055 3525 11072
      3537 11067

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

$$

McCollum

924 
WGUS75 KFGZ 230311
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
811 PM MST Thu Jul 22 2021

AZC017-230500-
/O.CON.KFGZ.FF.W.0085.000000T0000Z-210723T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Navajo AZ-
811 PM MST Thu Jul 22 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM MST THIS 
EVENING FOR NAVAJO COUNTY...

At 809 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2.25 and 3.25 inches of rain 
have fallen. Additional rainfall amounts of 0.25 to 0.5 inches are 
possible in the warned area. Flash flooding is ongoing.

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...
  Dilkon and areas up to 20 miles west.

This includes the following highways...
	State Route 87 between mile markers 369 and 381.

This includes the following streams and drainages...
  Tees Toh Wash and Coyote Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3550 11049 3538 11030 3515 11055 3525 11072
      3537 11067

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

$$

McCollum

996 
WGUS75 KFGZ 230357
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
857 PM MST Thu Jul 22 2021

AZC017-230500-
/O.CON.KFGZ.FF.W.0085.000000T0000Z-210723T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Navajo AZ-
857 PM MST Thu Jul 22 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM MST THIS 
EVENING FOR NAVAJO COUNTY...

At 854 PM MST, Doppler radar indicated thunderstorms that produced 
heavy rain earlier across the area including Dilkon and locations 
westward had weakened. Additional rainfall amounts up to 0.25 inches 
are possible in the warned area. Flash flooding is ongoing.

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

SOURCE...Radar.

IMPACT...Flash flooding of low-water crossings, creeks, normally
         dry washes and roads.

Some locations that will experience flash flooding include...
  Dilkon and location up to 20 miles west.

This includes the following highways...
	State Route 87 between mile markers 369 and 381.

This includes the following streams and drainages...
  Tees Toh Wash and Coyote Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3550 11049 3538 11030 3515 11055 3525 11072
      3537 11067

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

$$

McCollum

625 
WGUS75 KFGZ 230455
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
955 PM MST Thu Jul 22 2021

AZC017-230505-
/O.EXP.KFGZ.FF.W.0085.000000T0000Z-210723T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Navajo AZ-
955 PM MST Thu Jul 22 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 10 PM MST THIS EVENING FOR 
NAVAJO COUNTY...

Widespread heavy rain has ended in the Dilkon area. Lighter showers 
with a few embedded thunderstorms will continue until about 
midnight. Please continue to heed any road closures and be careful 
out there many roads are flooded or covered in water.

A Flash Flood Watch remains in effect until 1100 PM MST Saturday for 
portions of east central Arizona, north central Arizona, northeast 
Arizona and west central Arizona.

LAT...LON 3550 11049 3538 11030 3515 11055 3525 11072
      3537 11067

$$

McCollum

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 22, 8:01 PM MDT	Areal Flood Warning	FGZ	Navajo	5 min
Jul 22, 9:08 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Apache, Navajo	3 hr
Jul 22, 11:06 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Apache, Gila, Navajo	4 hr
Jul 23, 1:57 AM MDT	Flash Flood Warning Considerable damage threat	FGZ	Gila	4 hr
Jul 23, 2:50 AM MDT	Areal Flood Advisory	FGZ	Coconino, Gila, Yavapai	3 hr
Jul 23, 5:07 AM MDT	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	4 hr
Jul 23, 12:21 PM MDT	Areal Flood Warning	FGZ	Gila	6 hr
Jul 23, 12:38 PM MDT	Special Weather Statement	FGZ	Coconino	37 min
Jul 23, 1:07 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	4 hr
Jul 23, 1:14 PM MDT	Special Weather Statement	FGZ	Coconino	46 min
Jul 23, 1:19 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	2 hr
Jul 23, 1:51 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Coconino	114 min
Jul 23, 2:17 PM MDT	Special Weather Statement	FGZ		43 min
Jul 23, 2:31 PM MDT	Severe Thunderstorm Warning	FGZ	Yavapai	34 min
Jul 23, 3:12 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	2 hr
Jul 23, 3:24 PM MDT	Special Weather Statement	FGZ	Yavapai	36 min
Jul 23, 3:59 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Coconino	7 hr
Jul 23, 4:26 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	3 hr
Jul 23, 4:43 PM MDT	Special Weather Statement	FGZ	Navajo	47 min
Jul 23, 5:01 PM MDT	Areal Flood Advisory	FGZ	Yavapai	3 hr
Jul 23, 5:28 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Navajo	3 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.