Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 107, NWS Flagstaff, AZ

July 25, 2021Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 25, 2021, 2:52 PM MST for Yavapai 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 25, 2021, 2:52 PM MST (21:52 UTC)
Expired: Jul 25, 2021, 6:00 PM MST
In force: 3 hr
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 109 km from the middle of the area, began a volume at 21:53 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, 9.9 hours before the alert went out and 62 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: 4 J/kg
Mixed-layer CIN: -19 J/kg
Mixed-layer LCL: 803 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -30 m²/s²
0-3 km storm-relative helicity: 25 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

722 
WGUS55 KFGZ 252152
FFWFGZ
AZC025-260100-
/O.NEW.KFGZ.FF.W.0107.210725T2152Z-210726T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
252 PM MST Sun Jul 25 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  Yavapai County in west central Arizona...

* Until 600 PM MST.

* At 251 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 1.5 inches of 
  rain have fallen. Additional rainfall amounts of 0.5 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...
  mainly rural areas of Yavapai County

This includes the following streams and drainages...
  Verde River, Rattlesnake Wash, Wagon Tire Wash, Hell Canyon, Munds 
  Draw and Big Chino Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Remain alert for flooding even in locations not receiving rain. 
Normally dry washes, slot canyons and creeks can become raging 
killer currents in a matter of minutes, even from distant rainfall.

&&

LAT...LON 3498 11234 3478 11220 3475 11235 3490 11242

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

$$

TPS

1 follow-up statement

430 
WGUS75 KFGZ 260053
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
553 PM MST Sun Jul 25 2021

AZC025-260103-
/O.EXP.KFGZ.FF.W.0107.000000T0000Z-210726T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yavapai AZ-
553 PM MST Sun Jul 25 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 6 PM MST THIS EVENING FOR 
YAVAPAI COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please heed any road closures and avoid driving through 
water on 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 3498 11234 3478 11220 3475 11235 3490 11242

$$

McCollum

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 24, 5:30 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Navajo	30 min
Jul 24, 7:12 PM MST	Areal Flood Advisory	FGZ	Coconino, Navajo	3 hr
Jul 24, 7:50 PM MST	Areal Flood Advisory	FGZ	Coconino	3 hr
Jul 24, 8:49 PM MST	Areal Flood Advisory	FGZ	Coconino, Yavapai	3 hr
Jul 24, 9:32 PM MST	Areal Flood Advisory	FGZ	Yavapai	3 hr
Jul 24, 10:47 PM MST	Areal Flood Warning	FGZ	Navajo	6 hr
Jul 24, 11:06 PM MST	Areal Flood Advisory	FGZ	Apache, Coconino, Navajo	12 hr
Jul 25, 2:30 AM MST	Areal Flood Advisory	FGZ	Coconino, Navajo	24 hr
Jul 25, 2:51 AM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	6 hr
Jul 25, 4:58 AM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 25, 9:15 AM MST	Areal Flood Warning	FGZ	Apache, Coconino, Navajo	13 hr
Jul 25, 11:05 AM MST	Flash Flood Warning Considerable damage threat	FGZ	Navajo	11 hr
Jul 25, 12:39 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Gila, Yavapai	3 hr
Jul 25, 1:51 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 25, 2:27 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	108 min
Jul 25, 3:28 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	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.