Alert archive / Arizona / Flash Flood Warnings in 2023

Flash Flood Warning 29, NWS Flagstaff, AZ

August 12, 2023Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 12, 2023, 12:14 AM MST for Yavapai County, Arizona. It was in force for 8 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 12, 2023, 12:14 AM MST (07:14 UTC)
Expired: Aug 12, 2023, 7:54 AM MST
In force: 8 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 07:15 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 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 11, 9:23 PM MST, 2 hours 51 minutes earlier.

Area forecast discussion, Aug 11, 9:23 PM MST, 2 hours 51 minutes before

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In the hours before

Special weather statement, Aug 11, 6:29 PM MST, 5 hours 45 minutes before

Special Weather Statement
National Weather Service Flagstaff AZ
629 PM MST Fri Aug 11 2023

AZZ005-006-009-012-120200-
Little Colorado River Valley in Coconino County-Marble and Glen
Canyons-Northeast Plateaus and Mesas Hwy 264 Northward-Grand Canyon
Country-
629 PM MST Fri Aug 11 2023

...A STRONG THUNDERSTORM WILL IMPACT THE COLORADO RIVER NEAR THE
CONFLUENCE WITH THE LITTLE COLORADO RIVER IN COCONINO COUNTY THROUGH
700 PM MST...

At 626 PM MST, Doppler radar was tracking a strong thunderstorm over
Blue Water Base Camp near the confluence of the Colorado and Little
Colorado Rivers , or 10 miles north of Desert View at Grand Canyon,
moving northeast at 15 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
LCR Confluence Overlook and Blue Water Base Camp.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm.

If on or near the river, get out of the water. If you can hear
thunder, you are close enough to be struck by lightning. Move to
safe shelter now! Do not be caught on the water in a thunderstorm.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

&&

LAT...LON 3607 11172 3618 11190 3638 11176 3623 11150
TIME...MOT...LOC 0126Z 218DEG 15KT 3619 11176

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

MCT

Special weather statement, Aug 11, 7:17 PM MST, 4 hours 57 minutes before

Special Weather Statement
National Weather Service Flagstaff AZ
717 PM MST Fri Aug 11 2023

AZZ004-005-009-039-120315-
Kaibab Plateau-Black Mesa Area-Marble and Glen Canyons-Northeast
Plateaus and Mesas Hwy 264 Northward-
717 PM MST Fri Aug 11 2023

...STRONG THUNDERSTORMS WILL IMPACT AREAS NEAR PAGE AND LAKE POWELL
IN COCONINO COUNTY THROUGH 815 PM MST...

At 715 PM MST, Doppler radar was tracking strong thunderstorms near
Cathedral Wash Trailhead, or 15 miles west of Page, moving northeast
at 15 mph.

HAZARD...Wind gusts up to 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Page, Marble Canyon, Cliff Dwellers, Ramshead Canyon, Cathedral Wash
Trailhead, Coppermine Chapter House, Wahweap, Lees Ferry, Horseshoe
Bend, Tower Butte, Canyon X, LeChee, Lee's Ferry CG, Lower Antelope
Canyon, Antelope Island, Big Five, NMS Beach, Stud Horse Point, and
Antelope Pass Overlook.

This includes the following highways...
 State Route 98 between mile markers 548 and 549.
 U.S. Highway 89 between mile markers 504 and 556.
 U.S. Highway 89A between mile markers 524 and 555.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

If on or near Lake Powell, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.

&&

LAT...LON 3700 11125 3658 11094 3633 11160 3689 11202
      3700 11183
TIME...MOT...LOC 0215Z 238DEG 12KT 3688 11172

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

MCT

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 5:37 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Navajo	6 hr
Aug 11, 6:29 PM MST	Special Weather Statement	FGZ	Coconino	31 min
Aug 11, 6:47 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	28 min
Aug 11, 7:17 PM MST	Special Weather Statement	FGZ		58 min
Aug 11, 7:35 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	4 hr
Aug 11, 8:03 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	42 min
Aug 12, 1:10 AM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	8 hr
Aug 12, 11:31 AM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	4 hr
Aug 12, 11:57 AM MST	Special Weather Statement	FGZ		33 min
Aug 12, 1:05 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Gila	3 hr
Aug 12, 2:07 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Yavapai	20 min

Nearby

Flash Flood Warnings in Arizona, 2023 Every flash flood warning in 2023

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.