Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 21, NWS Flagstaff, AZ

July 10, 2021Apache County, Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 10, 2021, 4:27 PM MST for Apache County, Navajo County, Arizona. It was in force for 48 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 10, 2021, 4:27 PM MST (23:27 UTC)
Expired: Jul 10, 2021, 5:15 PM MST
In force: 48 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

Counties Apache County, AZ, Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 175 km from the middle of the area, began a volume at 23:26 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

Tuscon, AZ (KTUS), launched 12:00Z, 11.5 hours before the alert went out and 198 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: 1505 J/kg
Mixed-layer CIN: -302 J/kg
Mixed-layer LCL: 1767 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

502 
WUUS55 KFGZ 102327
SVRFGZ
AZC001-017-110015-
/O.NEW.KFGZ.SV.W.0021.210710T2327Z-210711T0015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
427 PM MST Sat Jul 10 2021

The National Weather Service in Flagstaff has issued a

* Severe Thunderstorm Warning for...
  Apache County in northeastern Arizona...
  Navajo County in north central Arizona...

* Until 515 PM MST.

* At 426 PM MST, a severe thunderstorm was located 14 miles east of
  Turkey Creek, or 36 miles southwest of Springerville, moving
  southwest at 10 mph.

  HAZARD...60 mph wind gusts and half dollar size hail.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Reservation Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 3364 10994 3386 10970 3384 10939 3362 10957
      3361 10961 3358 10962 3359 10963 3358 10967
      3357 10968 3356 10967 3352 10972 3352 10973
TIME...MOT...LOC 2326Z 026DEG 8KT 3373 10970 

HAIL...1.25IN
WIND...60MPH
 
$$

RR

3 follow-up statements

447 
WWUS55 KFGZ 102355
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
455 PM MST Sat Jul 10 2021

AZC001-017-110015-
/O.CON.KFGZ.SV.W.0021.000000T0000Z-210711T0015Z/
Apache-Navajo-
455 PM MST Sat Jul 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM MST
FOR APACHE AND NAVAJO COUNTIES...

At 454 PM MST, a severe thunderstorm was located 15 miles southeast
of Turkey Creek, or 41 miles southwest of Springerville, moving
southwest at 10 mph.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Reservation Lake.

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 3364 10994 3386 10970 3384 10939 3362 10957
      3361 10961 3358 10962 3359 10963 3358 10967
      3357 10968 3356 10967 3352 10972 3352 10973
TIME...MOT...LOC 2354Z 026DEG 8KT 3367 10973 

HAIL...1.25IN
WIND...60MPH
 
$$

RR

260 
WWUS55 KFGZ 110004
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
504 PM MST Sat Jul 10 2021

AZC001-017-110015-
/O.CON.KFGZ.SV.W.0021.000000T0000Z-210711T0015Z/
Apache-Navajo-
504 PM MST Sat Jul 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM MST
FOR APACHE AND NAVAJO COUNTIES...

At 504 PM MST, a severe thunderstorm was located 15 miles southeast
of Seven Mile, or 42 miles southwest of Springerville, moving
southwest at 10 mph.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

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

This severe thunderstorm will remain over mainly rural areas of
Apache and Navajo Counties.

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 3367 10990 3386 10970 3383 10958 3364 10965
      3359 10971
TIME...MOT...LOC 0004Z 026DEG 8KT 3365 10974 

HAIL...1.25IN
WIND...60MPH
 
$$

RR

828 
WWUS55 KFGZ 110010
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
510 PM MST Sat Jul 10 2021

AZC001-017-110020-
/O.EXP.KFGZ.SV.W.0021.000000T0000Z-210711T0015Z/
Apache-Navajo-
510 PM MST Sat Jul 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR APACHE AND NAVAJO COUNTIES
WILL EXPIRE AT 515 PM MST...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

LAT...LON 3367 10990 3386 10970 3383 10958 3364 10965
      3359 10971
TIME...MOT...LOC 0010Z 026DEG 8KT 3364 10974 

$$

RR

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 9, 5:00 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	45 min
Jul 9, 5:11 PM MST	Special Weather Statement	FGZ		34 min
Jul 9, 5:21 PM MST	Special Weather Statement	FGZ	Yavapai	39 min
Jul 9, 5:32 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	43 min
Jul 9, 5:40 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	35 min
Jul 9, 6:14 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	46 min
Jul 9, 7:14 PM MST	Special Weather Statement	FGZ	Gila	46 min
Jul 10, 12:36 PM MST	Special Weather Statement	FGZ	Apache	24 min
Jul 10, 1:29 PM MST	Areal Flood Advisory	FGZ	Apache	2 hr
Jul 10, 1:38 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Yavapai	31 min
Jul 10, 1:57 PM MST	Special Weather Statement	FGZ		33 min
Jul 10, 2:21 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	39 min
Jul 10, 2:40 PM MST	Areal Flood Advisory	FGZ	Gila	4 hr
Jul 10, 2:55 PM MST	Special Weather Statement	FGZ	Yavapai	50 min
Jul 10, 3:40 PM MST	Areal Flood Advisory	FGZ	Yavapai	3 hr
Jul 10, 4:18 PM MST	Severe Thunderstorm Warning	FGZ	Gila	27 min
Jul 10, 4:40 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Gila	3 hr
Jul 10, 4:40 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Navajo	50 min
Jul 10, 4:51 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Yavapai	24 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.