Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 108, NWS Flagstaff, AZ

July 25, 2021Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 25, 2021, 3:28 PM MST for Coconino 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 25, 2021, 3:28 PM MST (22:28 UTC)
Expired
Jul 25, 2021, 6:30 PM MST
In force
3 hr
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Coconino County, AZ

The radar

The Flagstaff radar (KFSX), 69 km from the middle of the area, began a volume at 22:31 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.

What was reported inside it

TimeReportWhereRemark
Jul 25, 3:50 PM MSTFLASH FLOOD5 Ssw Kachina Village, AZADOT REPORTS ROCKS IN ROADWAY ON SR-89 SOUTHBOUND NEAR NF-237.

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, 10.5 hours before the alert went out and 23 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-pSkew-T log-p diagram, Flgstf/Belemont, AZ at 12:00Z on 2021-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2021-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -30 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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.

989 
WGUS55 KFGZ 252228
FFWFGZ
AZC005-260130-
/O.NEW.KFGZ.FF.W.0108.210725T2228Z-210726T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Flagstaff has issued a

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

* Until 630 PM MST.

* At 327 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across Interstate 17 and State Route 89A north of 
  Sedona. Between 0.75 and 1.5 inches of rain have fallen. 
  Additional rainfall amounts of 0.25 to 0.75 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...
  Sterling Fish Hatchery, Pine Flat Campground, Cave Springs 
  Campground and West Fork Of Oak Creek.

This includes the following swimming holes...
	Pumphouse Wash.

This includes the following highways...
	State Route 89A between mile markers 385 and 391.
	Interstate 17 between mile markers 328 and 331.

This includes the following streams and drainages...
  Oak Creek and West Fork Oak 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 3506 11168 3502 11164 3498 11173 3502 11181
      3505 11176

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

$$

TPS
1 follow-up statement
355 
WGUS75 KFGZ 260132
FFSFGZ

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

AZC005-260142-
/O.EXP.KFGZ.FF.W.0108.000000T0000Z-210726T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coconino AZ-
632 PM MST Sun Jul 25 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR COCONINO COUNTY...

The heavy rain has ended north of Munds Park and along Highway 89A. 
Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

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

LAT...LON 3506 11168 3502 11164 3498 11173 3502 11181
      3505 11176

$$

McCollum

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 24, 5:30 PM MSTSevere Thunderstorm WarningFGZCoconino, Navajo30 min
Jul 24, 7:12 PM MSTAreal Flood AdvisoryFGZCoconino, Navajo3 hr
Jul 24, 7:50 PM MSTAreal Flood AdvisoryFGZCoconino3 hr
Jul 24, 8:49 PM MSTAreal Flood AdvisoryFGZCoconino, Yavapai3 hr
Jul 24, 9:32 PM MSTAreal Flood AdvisoryFGZYavapai3 hr
Jul 24, 10:47 PM MSTAreal Flood WarningFGZNavajo6 hr
Jul 24, 11:06 PM MSTAreal Flood AdvisoryFGZApache, Coconino, Navajo12 hr
Jul 25, 2:30 AM MSTAreal Flood AdvisoryFGZCoconino, Navajo24 hr
Jul 25, 2:51 AM MSTFlash Flood Warning Considerable damage threatFGZYavapai6 hr
Jul 25, 4:58 AM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr
Jul 25, 9:15 AM MSTAreal Flood WarningFGZApache, Coconino, Navajo13 hr
Jul 25, 11:05 AM MSTFlash Flood Warning Considerable damage threatFGZNavajo11 hr
Jul 25, 12:39 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino, Gila, Yavapai3 hr
Jul 25, 1:51 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Jul 25, 2:27 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino, Yavapai108 min
Jul 25, 2:52 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr

Nearby

Flash Flood Warnings in Arizona, 2021Every 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.