Alert archive / Arizona / Flash Flood Warnings in 2021
Flash Flood Warning 149, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this flash flood warning at Aug 2, 2021, 1:59 PM MST for Apache 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 2, 2021, 1:59 PM MST (20:59 UTC)
- Expired
- Aug 2, 2021, 5:00 PM MST
- In force
- 3 hr
- Issued by
- NWS Flagstaff, AZ
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County Apache County, AZ
The radar
The Flagstaff radar (KFSX), 230 km from the middle of the area, began a volume at 21:01 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, 9.0 hours before the alert went out and 215 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.
- Mixed-layer CAPE
- 321 J/kg
- Mixed-layer CIN
- -65 J/kg
- Mixed-layer LCL
- 1493 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 12 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
779
WGUS55 KFGZ 022059
FFWFGZ
AZC001-030000-
/O.NEW.KFGZ.FF.W.0149.210802T2059Z-210803T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
159 PM MST Mon Aug 2 2021
The National Weather Service in Flagstaff has issued a
* Flash Flood Warning for...
Apache County in northeastern Arizona...
* Until 500 PM MST.
* At 158 PM MST, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 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.
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...
Tselani-Cottonwood, Blue Gap Chapter House, Rough Rock and Navajo
Reservation.
This includes the following streams and drainages...
Balakai Wash, Black Mountain Wash, Sitting Giant Rock Wash, Oraibi
Wash, Burro Wash, Polacca Wash, Bitter Water Wash, Tah Chee Wash,
Chinle Wash, Trading Post Wash, Hipbone Wash and Cottonwood Wash.
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.
In hilly or mountainous terrain, there are many low water crossings
which will become dangerous in heavy rain. Do not attempt to cross
flooded roads. Find an alternate route.
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.
Report any flooding to local law enforcement and the NWS Flagstaff
when you can do so safely.
&&
LAT...LON 3643 10992 3641 10975 3639 10965 3621 10962
3608 10966 3605 10996 3639 10996 3641 10997
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
ET2 follow-up statements
333
WGUS75 KFGZ 022208
FFSFGZ
Flash Flood Statement
National Weather Service Flagstaff AZ
308 PM MST Mon Aug 2 2021
AZC001-030000-
/O.CON.KFGZ.FF.W.0149.000000T0000Z-210803T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
308 PM MST Mon Aug 2 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON FOR APACHE COUNTY...
At 307 PM MST, heavy rain had ended across the warned area. Between
1 and 1.5 inches of rain have fallen. Flash flooding is will
continue to be ongoing for the next few hours.
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...
Tselani-Cottonwood, Blue Gap Chapter House, Rough Rock and Navajo
Reservation.
This includes the following streams and drainages...
Balakai Wash, Black Mountain Wash, Sitting Giant Rock Wash, Oraibi
Wash, Burro Wash, Polacca Wash, Bitter Water Wash, Tah Chee Wash,
Chinle Wash, Trading Post Wash, Hipbone Wash and Cottonwood Wash.
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.
In hilly or mountainous terrain, there are many low water crossings
which will become dangerous in heavy rain. Do not attempt to cross
flooded roads. Find an alternate route.
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.
Report any flooding to local law enforcement and the NWS Flagstaff
when you can do so safely.
&&
LAT...LON 3643 10992 3641 10975 3639 10965 3621 10962
3608 10966 3605 10996 3639 10996 3641 10997
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
ET214
WGUS75 KFGZ 022354
FFSFGZ
Flash Flood Statement
National Weather Service Flagstaff AZ
454 PM MST Mon Aug 2 2021
AZC001-030004-
/O.EXP.KFGZ.FF.W.0149.000000T0000Z-210803T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Apache AZ-
454 PM MST Mon Aug 2 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 5 PM MST THIS AFTERNOON FOR
APACHE COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3643 10992 3641 10975 3639 10965 3621 10962
3608 10966 3605 10996 3639 10996 3641 10997
$$
MCTThe office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 5:05 PM MST | Areal Flood Advisory | FGZ | Coconino | 3 hr |
| Aug 1, 5:11 PM MST | Severe Thunderstorm Warning | FGZ | Gila, Navajo | 49 min |
| Aug 1, 5:22 PM MST | Flash Flood Warning | FGZ | Coconino | 3 hr |
| Aug 1, 5:28 PM MST | Flash Flood Warning | FGZ | Gila, Navajo | 5 hr |
| Aug 1, 5:49 PM MST | Areal Flood Advisory | FGZ | Coconino | 3 hr |
| Aug 1, 5:49 PM MST | Flash Flood Warning | FGZ | Apache, Navajo | 3 hr |
| Aug 1, 6:04 PM MST | Flash Flood Warning | FGZ | Coconino | 3 hr |
| Aug 1, 6:20 PM MST | Flash Flood Warning | FGZ | Gila, Navajo | 3 hr |
| Aug 1, 7:55 PM MST | Flash Flood Warning | FGZ | Gila | 2 hr |
| Aug 1, 8:26 PM MST | Flash Flood Warning | FGZ | Gila | 115 min |
| Aug 1, 8:59 PM MST | Flash Flood Warning | FGZ | Gila | 85 min |
| Aug 1, 9:47 PM MST | Special Weather Statement | FGZ | 28 min | |
| Aug 2, 2:23 PM MST | Severe Thunderstorm Warning | FGZ | Apache, Navajo | 22 min |
| Aug 2, 2:44 PM MST | Severe Thunderstorm Warning | FGZ | Apache, Navajo | 31 min |
| Aug 2, 4:06 PM MST | Special Weather Statement | FGZ | Apache | 39 min |
| Aug 2, 4:14 PM MST | Special Weather Statement | FGZ | 31 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.