Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 177, NWS Flagstaff, AZ

August 15, 2021Coconino County, Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 15, 2021, 2:33 PM MST for Coconino County, 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
Aug 15, 2021, 2:33 PM MST (21:33 UTC)
Expired
Aug 15, 2021, 5:30 PM MST
In force
3 hr
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

Counties Coconino County, AZ, Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 88 km from the middle of the area, began a volume at 21:36 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, 9.6 hours before the alert went out and 37 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 2021-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 9 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 2021-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
9 J/kg
Mixed-layer CIN
-172 J/kg
Mixed-layer LCL
2026 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

766 
WGUS55 KFGZ 152133
FFWFGZ
AZC005-025-160030-
/O.NEW.KFGZ.FF.W.0177.210815T2133Z-210816T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
233 PM MST Sun Aug 15 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  The Rafael Fire scar in...
  Coconino County in north central Arizona...
  Yavapai County in west central Arizona...

* Until 530 PM MST.

* At 231 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over the Rafael Fire scar. Between 0.5 and 1.5 inches 
  of rain have fallen. Flash flooding is ongoing or expected to 
  begin shortly.

  HAZARD...Life-threatening flash flooding. Thunderstorms
           producing flash flooding in and around the Rafael Fire
           scar, with elevated flow expected through Sycamore
           Canyon.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of areas in and around
           the Rafael Fire scar.

* Some locations that will experience flash flooding include...
  mainly rural areas of Coconino and Yavapai Counties

This includes the following swimming holes...
	Parsons Spring along Sycamore Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get to higher ground immediately! Flash flood waters and debris will 
inundate recreation trails crossing washes within and downstream of 
Sycamore Canyon and Creek, including Parsons and Dogie Trails.

&&

LAT...LON 3497 11218 3511 11204 3507 11190 3499 11191
      3498 11193 3494 11199 3491 11202 3478 11204
      3488 11216

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

$$

RR

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 12:37 PM MSTSpecial Weather StatementFGZ23 min
Aug 15, 12:52 PM MSTSevere Thunderstorm WarningFGZCoconino38 min
Aug 15, 1:22 PM MSTSevere Thunderstorm WarningFGZApache38 min
Aug 15, 1:43 PM MSTSevere Thunderstorm WarningFGZCoconino, Yavapai36 min
Aug 15, 2:17 PM MSTSevere Thunderstorm WarningFGZCoconino43 min
Aug 15, 2:42 PM MSTSevere Thunderstorm WarningFGZYavapai48 min
Aug 15, 3:36 PM MSTSevere Thunderstorm WarningFGZYavapai39 min
Aug 15, 3:49 PM MSTSevere Thunderstorm WarningFGZCoconino, Navajo26 min
Aug 15, 3:52 PM MSTSevere Thunderstorm WarningFGZNavajo23 min
Aug 15, 4:49 PM MSTSevere Thunderstorm WarningFGZApache41 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.