Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 142, NWS Flagstaff, AZ

August 16, 2021Apache County, Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 16, 2021, 3:06 PM MST for Apache County, Navajo County, Arizona. It was in force for 22 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 16, 2021, 3:06 PM MST (22:06 UTC)
Expired: Aug 16, 2021, 3:28 PM MST
In force: 22 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Apache County, AZ, Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 192 km from the middle of the area, began a volume at 22:05 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.

What was reported inside it

Time	Report	Where	Remark
Aug 16, 3:25 PM MST	HAIL 0.75	1 Ne Ganado, AZ

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 10.1 hours before the alert went out and 209 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: 428 J/kg
Mixed-layer CIN: -132 J/kg
Mixed-layer LCL: 1562 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 67 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

655 
WUUS55 KFGZ 162206
SVRFGZ
AZC001-017-162245-
/O.NEW.KFGZ.SV.W.0142.210816T2206Z-210816T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
406 PM MDT Mon Aug 16 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 445 PM MDT.

* At 405 PM MDT, a severe thunderstorm was located near Hubbell
  Trading Post National Historic Site, or 34 miles south of Chinle,
  moving southwest at 20 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Cornfields Chapter House, Kinlichee Chapter House, Burnside,
  Klagetoh, Hubbell Trading Post National Historic Site, Sunrise
  Springs and Ganado.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3581 10958 3571 10933 3541 10943 3555 10983
TIME...MOT...LOC 2205Z 025DEG 16KT 3566 10953 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

DB

1 follow-up statement

704 
WWUS55 KFGZ 162228
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
428 PM MDT Mon Aug 16 2021

AZC001-017-162238-
/O.CAN.KFGZ.SV.W.0142.000000T0000Z-210816T2245Z/
Apache-Navajo-
428 PM MDT Mon Aug 16 2021

...THE SEVERE THUNDERSTORM WARNING FOR APACHE AND NAVAJO 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 3581 10958 3571 10933 3541 10943 3555 10983
TIME...MOT...LOC 2226Z 025DEG 16KT 3557 10958 

$$

ET

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 15, 5:29 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Navajo	31 min
Aug 15, 5:47 PM MST	Severe Thunderstorm Warning	FGZ	Apache	18 min
Aug 15, 6:17 PM MST	Severe Thunderstorm Warning	FGZ	Apache	12 min
Aug 15, 6:54 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	36 min
Aug 15, 7:46 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	29 min
Aug 15, 7:53 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	26 min
Aug 15, 8:17 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Aug 15, 8:29 PM MST	Severe Thunderstorm Warning	FGZ	Gila	31 min
Aug 15, 10:27 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	33 min
Aug 15, 11:01 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	29 min
Aug 15, 11:06 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	24 min
Aug 15, 11:27 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	21 min
Aug 15, 11:50 PM MST	Special Weather Statement	FGZ	Yavapai	25 min
Aug 16, 12:08 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	37 min
Aug 16, 12:40 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	35 min
Aug 16, 1:00 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	45 min
Aug 16, 11:55 AM MST	Special Weather Statement	FGZ	Apache	35 min
Aug 16, 1:30 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	45 min
Aug 16, 1:38 PM MST	Severe Thunderstorm Warning	FGZ	Navajo	52 min
Aug 16, 1:47 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	43 min
Aug 16, 2:09 PM MST	Flash Flood Warning	FGZ	Navajo	3 hr
Aug 16, 2:16 PM MST	Flash Flood Warning	FGZ	Coconino	3 hr
Aug 16, 2:25 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	50 min
Aug 16, 2:27 PM MST	Severe Thunderstorm Warning Considerable damage threat	FGZ	Coconino, Navajo	33 min
Aug 16, 2:30 PM MST	Severe Thunderstorm Warning	FGZ	Apache, Navajo	45 min
Aug 16, 2:38 PM MST	Severe Thunderstorm Warning Considerable damage threat	FGZ	Coconino, Gila, Navajo	37 min
Aug 16, 2:41 PM MST	Severe Thunderstorm Warning Considerable damage threat	FGZ	Coconino, Yavapai	34 min
Aug 16, 3:10 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Apache	3 hr
Aug 16, 3:39 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Gila	36 min
Aug 16, 3:57 PM MST	Severe Thunderstorm Warning	FGZ	Apache	33 min
Aug 16, 4:25 PM MST	Severe Thunderstorm Warning	FGZ	Apache	35 min
Aug 16, 4:34 PM MST	Severe Thunderstorm Warning	FGZ	Gila	26 min
Aug 16, 4:42 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Apache	4 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.