Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 64, NWS Flagstaff, AZ

July 22, 2021Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 22, 2021, 3:01 PM MST for Coconino County, Arizona. It was in force for 44 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 22, 2021, 3:01 PM MST (22:01 UTC)
Expired: Jul 22, 2021, 3:45 PM MST
In force: 44 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Coconino County, AZ

The radar

The Cedar City radar (KICX), 136 km from the middle of the area, began a volume at 22:00 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, 10.0 hours before the alert went out and 168 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: 196 J/kg
Mixed-layer CIN: -125 J/kg
Mixed-layer LCL: 1415 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 54 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

163 
WUUS55 KFGZ 222201
SVRFGZ
AZC005-222245-
/O.NEW.KFGZ.SV.W.0064.210722T2201Z-210722T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
301 PM MST Thu Jul 22 2021

The National Weather Service in Flagstaff has issued a

* Severe Thunderstorm Warning for...
  Coconino County in north central Arizona...

* Until 345 PM MST/445 PM MDT/.

* At 300 PM MST/400 PM MDT/, a severe thunderstorm was located 7
  miles southwest of Marble Canyon, or 19 miles southwest of Page,
  moving southeast at 20 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Bitter Springs. Highway 89A southwest of Marble Canyon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3678 11190 3688 11173 3671 11152 3656 11172
TIME...MOT...LOC 2200Z 321DEG 17KT 3675 11174 

HAIL...1.00IN
WIND...60MPH
 
$$
JJ

2 follow-up statements

218 
WWUS55 KFGZ 222217
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
317 PM MST Thu Jul 22 2021

AZC005-222245-
/O.CON.KFGZ.SV.W.0064.000000T0000Z-210722T2245Z/
Coconino-
317 PM MST Thu Jul 22 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 PM
MST/445 PM MDT/ FOR COCONINO COUNTY...

At 316 PM MST/416 PM MDT/, a severe thunderstorm was located near
Bitter Springs, or 16 miles southwest of Page, moving southeast at 20
mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Bitter Springs. Highway 89A just south of Marble Canyon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3674 11182 3683 11169 3671 11152 3656 11172
TIME...MOT...LOC 2216Z 303DEG 17KT 3672 11164 

HAIL...1.00IN
WIND...60MPH
 
$$
JJ

397 
WWUS55 KFGZ 222245
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
345 PM MST Thu Jul 22 2021

AZC005-222254-
/O.EXP.KFGZ.SV.W.0064.000000T0000Z-210722T2245Z/
Coconino-
345 PM MST Thu Jul 22 2021

...THE SEVERE THUNDERSTORM WARNING FOR COCONINO COUNTY WILL EXPIRE AT
345 PM MST/445 PM MDT/...
        
The storm which prompted the warning south of Marble Canyon has 
weakened below severe limits, and has exited the warned area. 
Therefore, the warning will be allowed to expire.  However heavy 
rain is still occurring with this thunderstorm and a Flash Flood 
Warning is in effect.

LAT...LON 3674 11182 3683 11169 3671 11152 3656 11172
TIME...MOT...LOC 2244Z 321DEG 17KT 3662 11154 

$$
JJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 6:38 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Gila	3 hr
Jul 21, 6:53 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	112 min
Jul 22, 12:28 PM MST	Areal Flood Advisory	FGZ	Coconino	3 hr
Jul 22, 2:10 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 22, 3:31 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	115 min
Jul 22, 3:58 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Navajo	3 hr
Jul 22, 4:04 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	116 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2021 Every severe thunderstorm 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.