Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 59, NWS Flagstaff, AZ

July 19, 2021Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 19, 2021, 2:08 PM MST for Coconino County, Arizona. It was in force for 37 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 19, 2021, 2:08 PM MST (21:08 UTC)
Expired: Jul 19, 2021, 2:45 PM MST
In force: 37 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

County Coconino County, AZ

The radar

The Flagstaff radar (KFSX), 117 km from the middle of the area, began a volume at 21:11 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, 9.1 hours before the alert went out and 32 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: 96 J/kg
Mixed-layer CIN: -89 J/kg
Mixed-layer LCL: 1290 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 68 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

132 
WUUS55 KFGZ 192108
SVRFGZ
AZC005-192145-
/O.NEW.KFGZ.SV.W.0059.210719T2108Z-210719T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
208 PM MST Mon Jul 19 2021

The National Weather Service in Flagstaff has issued a

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

* Until 245 PM MST.

* At 207 PM MST, a severe thunderstorm was located over Williams, or
  30 miles west of Flagstaff, and is nearly stationary.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Williams and Kaibab Lake Campground. 

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 3524 11211 3523 11219 3533 11225 3535 11208
TIME...MOT...LOC 2107Z 169DEG 2KT 3527 11215 

HAIL...1.00IN
WIND...<50MPH
 
$$
JJ

1 follow-up statement

807 
WWUS55 KFGZ 192136
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
236 PM MST Mon Jul 19 2021

AZC005-192145-
/O.EXP.KFGZ.SV.W.0059.000000T0000Z-210719T2145Z/
Coconino-
236 PM MST Mon Jul 19 2021

...THE SEVERE THUNDERSTORM WARNING FOR COCONINO COUNTY WILL EXPIRE AT
245 PM MST...
                
The storm which prompted the warning has weakened below severe 
limits. Therefore, the warning will be allowed to expire.  However 
heavy rain is occurring with this storm and a Flash Flood Warning 
has been issued.

LAT...LON 3524 11211 3523 11219 3533 11225 3535 11208
TIME...MOT...LOC 2135Z 169DEG 2KT 3528 11215 

$$
JJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 5:31 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Gila	59 min
Jul 18, 5:43 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Yavapai	24 min
Jul 18, 6:14 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 18, 6:21 PM MST	Special Weather Statement	FGZ		24 min
Jul 19, 1:48 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 19, 1:54 PM MST	Special Weather Statement	FGZ		51 min
Jul 19, 2:30 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	2 hr
Jul 19, 3:07 PM MST	Special Weather Statement	FGZ		23 min
Jul 19, 3:28 PM MST	Special Weather Statement	FGZ		32 min
Jul 19, 3:37 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 19, 4:01 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Navajo	3 hr
Jul 19, 4:27 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	2 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.