Alert archive / Arizona / Flash Flood Warnings in 2022

Flash Flood Warning 246, NWS Flagstaff, AZ

August 19, 2022Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 19, 2022, 4:45 PM MST for Yavapai County, Arizona. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 19, 2022, 4:45 PM MST (23:45 UTC)
Expired: Aug 19, 2022, 9:45 PM MST
In force: 5 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), 124 km from the middle of the area, began a volume at 23:47 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, 11.8 hours before the alert went out and 98 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: 44 J/kg
Mixed-layer CIN: -141 J/kg
Mixed-layer LCL: 3030 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 28 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Flagstaff, AZ wrote its last area forecast discussion before this flash flood warning went out at Aug 19, 2:27 PM MST, 2 hours 18 minutes earlier.

Area forecast discussion, Aug 19, 2:27 PM MST, 2 hours 18 minutes before

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In the hours before

Local storm report, Aug 19, 12:30 PM MST, 4 hours 15 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1230 PM MST FRI AUG 19 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0745 PM     FLASH FLOOD      1 E JOSEPH CITY         34.96N 110.31W
08/18/2022                   NAVAJO             AZ   DEPT OF HIGHWAYS

            INTERSTATE 40 WAS CLOSED DUE TO FLOODING ON
            THE EASTERN SIDE OF JOSEPH CITY.

&&

MAS

Special weather statement, Aug 19, 4:04 PM MST, 41 minutes before

Special Weather Statement
National Weather Service Flagstaff AZ
404 PM MST Fri Aug 19 2022

AZZ006-007-192315-
Coconino Plateau-Grand Canyon Country-
404 PM MST Fri Aug 19 2022

...A strong thunderstorm will impact portions of the Colorado River
West of Supai through 415 PM MST...

At 403 PM MST, Doppler radar was tracking a strong thunderstorm 8
miles east of Toroweap Campground, moving southeast at 15 mph.

HAZARD...Winds in excess of 30 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could blow around unsecured objects and make
         boating difficult. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Colorado Rive West of Supai.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead
to localized flooding. Get to relatively higher ground if you are in
a canyon.

&&

LAT...LON 3624 11300 3623 11298 3624 11294 3626 11292
      3625 11291 3626 11289 3628 11287 3628 11284
      3629 11282 3625 11272 3608 11290 3619 11304
TIME...MOT...LOC 2303Z 300DEG 14KT 3623 11291

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...30 MPH

TM

Special weather statement, Aug 19, 4:34 PM MST, 11 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 5:35 PM MST	Special Weather Statement	FGZ	Navajo	25 min
Aug 18, 6:19 PM MST	Special Weather Statement	FGZ		26 min
Aug 18, 8:07 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	8 hr
Aug 19, 4:29 AM MST	Areal Flood Advisory	FGZ	Apache	3 hr
Aug 19, 8:43 AM MST	Areal Flood Warning	FGZ	Coconino	10 hr
Aug 19, 3:55 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Gila	6 hr
Aug 19, 4:04 PM MST	Special Weather Statement	FGZ		11 min
Aug 19, 4:34 PM MST	Special Weather Statement	FGZ		26 min

Nearby

Flash Flood Warnings in Arizona, 2022 Every flash flood warning in 2022

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.