Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 95, NWS Flagstaff, AZ

August 10, 2021Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 10, 2021, 11:55 AM MST for Coconino County, Arizona. It was in force for 15 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: Aug 10, 2021, 11:55 AM MST (18:55 UTC)
Expired: Aug 10, 2021, 12:10 PM MST
In force: 15 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 Flagstaff radar (KFSX), 73 km from the middle of the area, began a volume at 18:58 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, 6.9 hours before the alert went out and 18 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: 609 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 962 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 118 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

525 
WUUS55 KFGZ 101855
SVRFGZ
AZC005-101930-
/O.NEW.KFGZ.SV.W.0095.210810T1855Z-210810T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
1155 AM MST Tue Aug 10 2021

The National Weather Service in Flagstaff has issued a

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

* Until 1230 PM MST.

* At 1155 AM MST, a severe thunderstorm was located over
  Mountainaire, or near Flagstaff, moving southwest at 10 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...
  Flagstaff, Kachina Village, Mountainaire and Lower Lake Mary. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3517 11167 3510 11157 3499 11165 3510 11182
TIME...MOT...LOC 1855Z 040DEG 10KT 3512 11165 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

TPS

1 follow-up statement

326 
WWUS55 KFGZ 101910
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
1210 PM MST Tue Aug 10 2021

AZC005-101919-
/O.CAN.KFGZ.SV.W.0095.000000T0000Z-210810T1930Z/
Coconino-
1210 PM MST Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR COCONINO COUNTY IS
CANCELLED...
                
The storm which prompted the warning near Flagstaff and Kachina 
Village has weakened below severe limits. Therefore, the warning has 
been cancelled. However, a Flash Flood Warning is in effect until 
3:00 PM MST for this area due to very heavy rainfall.

LAT...LON 3517 11167 3510 11157 3499 11165 3510 11182
TIME...MOT...LOC 1903Z 040DEG 10KT 3509 11168 

$$

TPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 5:19 PM MST	Special Weather Statement	FGZ		41 min
Aug 9, 6:17 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Aug 9, 6:56 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	34 min
Aug 9, 7:27 PM MST	Special Weather Statement	FGZ		33 min
Aug 9, 7:50 PM MST	Special Weather Statement	FGZ	Gila	25 min
Aug 9, 8:44 PM MST	Special Weather Statement	FGZ	Gila	46 min
Aug 9, 9:18 PM MST	Areal Flood Advisory	FGZ	Gila, Navajo	3 hr
Aug 9, 9:32 PM MST	Special Weather Statement	FGZ	Gila	43 min
Aug 10, 11:35 AM MST	Special Weather Statement	FGZ		25 min
Aug 10, 12:02 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Aug 10, 12:14 PM MST	Special Weather Statement	FGZ		31 min
Aug 10, 12:46 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Aug 10, 12:59 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	3 hr
Aug 10, 1:22 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	53 min
Aug 10, 2:22 PM MST	Special Weather Statement	FGZ	Yavapai	23 min
Aug 10, 2:26 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	32 min
Aug 10, 2:35 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	40 min
Aug 10, 2:43 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Aug 10, 2:52 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Yavapai	38 min
Aug 10, 3:11 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	3 hr
Aug 10, 3:46 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Aug 10, 4:13 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.