Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 182, NWS Flagstaff, AZ

August 16, 2021Apache County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 16, 2021, 4:42 PM MST for Apache County, Arizona. It was in force for 4 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: Aug 16, 2021, 4:42 PM MST (23:42 UTC)
Expired: Aug 16, 2021, 8:45 PM MST
In force: 4 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), 146 km from the middle of the area, began a volume at 23:42 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
Aug 16, 4:47 PM MST	FLOOD	Concho, AZ	MANY ROADS FLOODED. WATER UP TO THE DOORSTEP OF THE BUSINESS THAT WAS CONTACTED.

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, 11.7 hours before the alert went out and 215 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: 428 J/kg
Mixed-layer CIN: -132 J/kg
Mixed-layer LCL: 1562 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 67 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

876 
WGUS55 KFGZ 162342
FFWFGZ
AZC001-170245-
/O.NEW.KFGZ.FF.W.0182.210816T2342Z-210817T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
442 PM MST Mon Aug 16 2021

The National Weather Service in Flagstaff has issued a

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

* Until 745 PM MST.

* At 441 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 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...
  Concho.

This includes the following highways...
	State Route 61 between mile markers 369 and 374.
	Highway 180 near mile marker 349.

This includes the following streams and drainages...
  Oso Draw, Little Colorado River and Concho Creek.

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 3455 10966 3454 10959 3456 10959 3460 10957
      3460 10956 3459 10956 3453 10957 3441 10957
      3443 10966 3447 10969

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

$$

ET

4 follow-up statements

314 
WGUS75 KFGZ 170021
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
521 PM MST Mon Aug 16 2021

AZC001-170245-
/O.CON.KFGZ.FF.W.0182.000000T0000Z-210817T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
521 PM MST Mon Aug 16 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM MST THIS 
EVENING FOR APACHE COUNTY...

At 521 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 4 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...
  Concho.

This includes the following highways...
	State Route 61 between mile markers 369 and 374.
	Highway 180 near mile marker 349.

This includes the following streams and drainages...
  Oso Draw, Little Colorado River and Concho Creek.

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 3455 10966 3454 10959 3456 10959 3460 10957
      3460 10956 3459 10956 3453 10957 3441 10957
      3443 10966 3447 10969

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

$$

ET

358 
WGUS55 KFGZ 170230
FFWFGZ
AZC001-170345-
/O.EXT.KFGZ.FF.W.0182.000000T0000Z-210817T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
730 PM MST Mon Aug 16 2021

The National Weather Service in Flagstaff has extended the

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

* Until 845 PM MST.

* At 729 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4 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...
  Concho.

This includes the following highways...
	State Route 61 between mile markers 369 and 374.
	Highway 180 near mile marker 349.

This includes the following streams and drainages...
  Oso Draw, Little Colorado River and Concho Creek.

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 3455 10966 3454 10959 3456 10959 3460 10957
      3460 10956 3459 10956 3453 10957 3441 10957
      3443 10966 3447 10969

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

$$

ET

760 
WGUS75 KFGZ 170232
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
732 PM MST Mon Aug 16 2021

AZC001-170345-
/O.CON.KFGZ.FF.W.0182.000000T0000Z-210817T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
732 PM MST Mon Aug 16 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM MST THIS 
EVENING FOR APACHE COUNTY...

At 730 PM MST, heavy rain had ended across the warned area. Between 
2 and 4 inches of rain fell earlier today. Road closures due to 
flash flooding have been reported in Concho by ADOT along US 180A 
near MP347. Please avoid any flooded areas and heed road closures!

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...
  Concho.

This includes the following highways...
	State Route 61 between mile markers 369 and 374.
	Highway 180 near mile marker 349.

This includes the following streams and drainages...
  Oso Draw, Little Colorado River and Concho Creek.

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 3455 10966 3454 10959 3456 10959 3460 10957
      3460 10956 3459 10956 3453 10957 3441 10957
      3443 10966 3447 10969

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

$$

ET

813 
WGUS75 KFGZ 170337
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
837 PM MST Mon Aug 16 2021

AZC001-170347-
/O.EXP.KFGZ.FF.W.0182.000000T0000Z-210817T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
837 PM MST Mon Aug 16 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 845 PM MST THIS EVENING FOR 
APACHE COUNTY...

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

LAT...LON 3455 10966 3454 10959 3456 10959 3460 10957
      3460 10956 3459 10956 3453 10957 3441 10957
      3443 10966 3447 10969

$$

ET

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 15, 5:29 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Navajo	31 min
Aug 15, 5:47 PM MST	Severe Thunderstorm Warning	FGZ	Apache	18 min
Aug 15, 6:17 PM MST	Severe Thunderstorm Warning	FGZ	Apache	12 min
Aug 15, 6:54 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	36 min
Aug 15, 7:46 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	29 min
Aug 15, 7:53 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	26 min
Aug 15, 8:17 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Aug 15, 8:29 PM MST	Severe Thunderstorm Warning	FGZ	Gila	31 min
Aug 15, 10:27 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	33 min
Aug 15, 11:01 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	29 min
Aug 15, 11:06 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	24 min
Aug 15, 11:27 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	21 min
Aug 15, 11:50 PM MST	Special Weather Statement	FGZ	Yavapai	25 min
Aug 16, 12:08 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	37 min
Aug 16, 12:40 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	35 min
Aug 16, 1:00 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	45 min
Aug 16, 11:55 AM MST	Special Weather Statement	FGZ	Apache	35 min
Aug 16, 1:30 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	45 min
Aug 16, 1:38 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	52 min
Aug 16, 1:47 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	43 min
Aug 16, 2:09 PM MST	Flash Flood Warning	FGZ	Navajo	3 hr
Aug 16, 2:16 PM MST	Flash Flood Warning	FGZ	Coconino	3 hr
Aug 16, 2:25 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	50 min
Aug 16, 2:27 PM MST	Severe Thunderstorm Warning Considerable damage threat	FGZ	Coconino, Navajo	33 min
Aug 16, 2:30 PM MST	Severe Thunderstorm Warning	FGZ	Apache, Navajo	45 min
Aug 16, 2:38 PM MST	Severe Thunderstorm Warning Considerable damage threat	FGZ	Coconino, Gila, Navajo	37 min
Aug 16, 2:41 PM MST	Severe Thunderstorm Warning Considerable damage threat	FGZ	Coconino, Yavapai	34 min
Aug 16, 3:06 PM MST	Severe Thunderstorm Warning	FGZ	Apache, Navajo	22 min
Aug 16, 3:10 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Apache	3 hr
Aug 16, 3:39 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Gila	36 min
Aug 16, 3:57 PM MST	Severe Thunderstorm Warning	FGZ	Apache	33 min
Aug 16, 4:25 PM MST	Severe Thunderstorm Warning	FGZ	Apache	35 min
Aug 16, 4:34 PM MST	Severe Thunderstorm Warning	FGZ	Gila	26 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.