Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 18, NWS Flagstaff, AZ

July 10, 2021Coconino County, Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 10, 2021, 1:38 PM MST for Coconino County, Yavapai County, Arizona. It was in force for 31 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, 1:38 PM MST (20:38 UTC)
Expired: Jul 10, 2021, 2:09 PM MST
In force: 31 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Coconino County, AZ, Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 104 km from the middle of the area, began a volume at 20:39 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, 8.6 hours before the alert went out and 36 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: 110 J/kg
Mixed-layer CIN: -242 J/kg
Mixed-layer LCL: 2626 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 37 m²/s²
0-3 km storm-relative helicity: 131 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

193 
WUUS55 KFGZ 102038
SVRFGZ
AZC005-025-102130-
/O.NEW.KFGZ.SV.W.0018.210710T2038Z-210710T2130Z/

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

The National Weather Service in Flagstaff has issued a

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

* Until 230 PM MST.

* At 137 PM MST, a severe thunderstorm was located 10 miles north of
  Perkinsville, or 24 miles northwest of Sedona, moving west at 5
  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.

* This severe thunderstorm will remain over mainly rural areas of
  Yavapai and Coconino 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 3517 11211 3498 11204 3492 11224 3518 11229
TIME...MOT...LOC 2037Z 098DEG 6KT 3505 11216 

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

NL

3 follow-up statements

341 
WWUS55 KFGZ 102051
SVSFGZ

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

AZC005-025-102130-
/O.CON.KFGZ.SV.W.0018.000000T0000Z-210710T2130Z/
Yavapai-Coconino-
151 PM MST Sat Jul 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 PM MST
FOR YAVAPAI AND COCONINO COUNTIES...

At 149 PM MST, radar continues to show a severe thunderstorm located 
10 miles north of Perkinsville, or 25 miles northeast of Chino 
Valley, moving west at 5 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.

This severe thunderstorm will remain over mainly rural areas of
Yavapai and Coconino 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 3513 11211 3498 11205 3492 11224 3513 11228
TIME...MOT...LOC 2049Z 098DEG 6KT 3505 11219 

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

NL

379 
WWUS55 KFGZ 102101
SVSFGZ

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

AZC005-025-102130-
/O.CON.KFGZ.SV.W.0018.000000T0000Z-210710T2130Z/
Yavapai-Coconino-
201 PM MST Sat Jul 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 PM MST
FOR YAVAPAI AND COCONINO COUNTIES...

At 201 PM MST, a severe thunderstorm was located 10 miles north of
Perkinsville, or 24 miles northeast of Chino Valley, moving west at 5
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.

This severe thunderstorm will remain over mainly rural areas of
Yavapai and Coconino Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 3506 11213 3496 11212 3492 11224 3506 11227
TIME...MOT...LOC 2101Z 098DEG 6KT 3505 11222 

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

NL

932 
WWUS55 KFGZ 102109
SVSFGZ

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

AZC005-025-102118-
/O.CAN.KFGZ.SV.W.0018.000000T0000Z-210710T2130Z/
Yavapai-Coconino-
209 PM MST Sat Jul 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR YAVAPAI AND COCONINO COUNTIES
IS CANCELLED...
                
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 has been cancelled. However gusty winds and 
heavy rain are still possible with this thunderstorm.

LAT...LON 3506 11213 3496 11212 3492 11224 3506 11227
TIME...MOT...LOC 2102Z 098DEG 6KT 3505 11224 

$$

NL

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, 1:57 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, 4:27 PM MST	Severe Thunderstorm Warning	FGZ	Apache, Navajo	48 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.