Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 17, NWS Flagstaff, AZ

July 9, 2021Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 9, 2021, 7:14 PM MDT for Navajo County, Arizona. It was in force for 46 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 9, 2021, 7:14 PM MDT (01:14 UTC)
Expired
Jul 9, 2021, 8:00 PM MDT
In force
46 min
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 75 km from the middle of the area, began a volume at 01:16 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 00:00Z, 1.2 hours before the alert went out and 152 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-pSkew-T log-p diagram, Flgstf/Belemont, AZ at 00:00Z on 2021-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 49 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 00:00Z on 2021-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 49 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
49 J/kg
Mixed-layer CIN
-141 J/kg
Mixed-layer LCL
3400 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

558 
WUUS55 KFGZ 100114
SVRFGZ
AZC017-100200-
/O.NEW.KFGZ.SV.W.0017.210710T0114Z-210710T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
614 PM MST Fri Jul 9 2021

The National Weather Service in Flagstaff has issued a

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

* Until 700 PM MST.

* At 612 PM MST, a severe thunderstorm was located 9 miles northeast
  of Aripine, or 26 miles northwest of Show Low, moving southwest at
  15 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...
  Aripine. Heber-Overgaard.

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 3463 11036 3451 11021 3433 11040 3445 11060
TIME...MOT...LOC 0112Z 042DEG 15KT 3452 11035 

HAIL...1.00IN
WIND...60MPH
 
$$
JJ
2 follow-up statements
829 
WWUS55 KFGZ 100137
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
637 PM MST Fri Jul 9 2021

AZC017-100200-
/O.CON.KFGZ.SV.W.0017.000000T0000Z-210710T0200Z/
Navajo-
637 PM MST Fri Jul 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM MST
FOR NAVAJO COUNTY...

At 635 PM MST, a severe thunderstorm was located just north of 
Aripine, or 22 miles northeast of Forest Lakes, moving southwest at 
15 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...
Aripine. Highways 277 and 377 northeast of Heber.

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 3459 11042 3447 11028 3435 11043 3445 11060
TIME...MOT...LOC 0135Z 054DEG 15KT 3448 11046 

HAIL...1.00IN
WIND...60MPH
 
$$
JJ
924 
WWUS55 KFGZ 100202
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
702 PM MST Fri Jul 9 2021

AZC017-100211-
/O.EXP.KFGZ.SV.W.0017.000000T0000Z-210710T0200Z/
Navajo-
702 PM MST Fri Jul 9 2021

...THE SEVERE THUNDERSTORM WARNING FOR NAVAJO COUNTY HAS EXPIRED...
                
The storm which prompted the warning near Aripine and Heber has 
weakened below severe limits. Therefore, the warning has been 
allowed to expire.  However gusty winds to 45 mph and heavy rain are 
still occurring with this thunderstorm.

LAT...LON 3459 11042 3447 11028 3435 11043 3445 11060
TIME...MOT...LOC 0201Z 042DEG 15KT 3441 11053 

$$
JJ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 6:00 PM MDTSevere Thunderstorm WarningFGZYavapai45 min
Jul 9, 6:11 PM MDTSpecial Weather StatementFGZ34 min
Jul 9, 6:21 PM MDTSpecial Weather StatementFGZYavapai39 min
Jul 9, 6:32 PM MDTSevere Thunderstorm WarningFGZNavajo43 min
Jul 9, 6:40 PM MDTSevere Thunderstorm WarningFGZYavapai35 min
Jul 9, 8:14 PM MDTSpecial Weather StatementFGZGila46 min
Jul 10, 1:36 PM MDTSpecial Weather StatementFGZApache24 min
Jul 10, 2:29 PM MDTAreal Flood AdvisoryFGZApache2 hr
Jul 10, 2:38 PM MDTSevere Thunderstorm WarningFGZCoconino, Yavapai31 min
Jul 10, 2:57 PM MDTSpecial Weather StatementFGZ33 min
Jul 10, 3:21 PM MDTSevere Thunderstorm WarningFGZYavapai39 min
Jul 10, 3:40 PM MDTAreal Flood AdvisoryFGZGila4 hr
Jul 10, 3:55 PM MDTSpecial Weather StatementFGZYavapai50 min
Jul 10, 4:40 PM MDTAreal Flood AdvisoryFGZYavapai3 hr
Jul 10, 5:18 PM MDTSevere Thunderstorm WarningFGZGila27 min
Jul 10, 5:27 PM MDTSevere Thunderstorm WarningFGZApache, Navajo48 min
Jul 10, 5:40 PM MDTFlash Flood Warning Considerable damage threatFGZGila3 hr
Jul 10, 5:40 PM MDTSevere Thunderstorm WarningFGZGila, Navajo50 min
Jul 10, 5:51 PM MDTSevere Thunderstorm WarningFGZCoconino, Yavapai24 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2021Every 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.