Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 96, NWS Flagstaff, AZ

July 23, 2021Navajo County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 23, 2021, 5:28 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 23, 2021, 5:28 PM MDT (23:28 UTC)
Expired: Jul 23, 2021, 8:09 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), 112 km from the middle of the area, began a volume at 23:31 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 12:00Z, 11.5 hours before the alert went out and 141 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: 503 J/kg
Mixed-layer CIN: -51 J/kg
Mixed-layer LCL: 915 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 109 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

779 
WGUS55 KFGZ 232328
FFWFGZ
AZC017-240230-
/O.NEW.KFGZ.FF.W.0096.210723T2328Z-210724T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
428 PM MST Fri Jul 23 2021

The National Weather Service in Flagstaff has issued a

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

* Until 730 PM MST.

* At 425 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...
  The area 2 to 15 miles southwest of Indian Wells.

This includes the following highways...
	State Route 77 between mile markers 405 and 408.

This includes the following streams and drainages...
  Bidahochi Wash andPueblo Colorado Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3538 11021 3524 10996 3503 11018 3506 11036
      3514 11045 3525 11037

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

$$

McCollum

1 follow-up statement

328 
WGUS75 KFGZ 240209
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
709 PM MST Fri Jul 23 2021

AZC017-240219-
/O.CAN.KFGZ.FF.W.0096.000000T0000Z-210724T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Navajo AZ-
709 PM MST Fri Jul 23 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NAVAJO COUNTY...

The heavy rain has ended across the area southwest of Indian Wells. 
Flooding is no longer expected to pose a threat. Please heed any 
road closures and avoid driving over water covered 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 3538 11021 3524 10996 3503 11018 3506 11036
      3514 11045 3525 11037

$$

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, 8:06 PM MDT	Flash Flood Warning Considerable damage threat	FGZ	Navajo	3 hr
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

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.