Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 69, NWS Tucson, AZ

July 18, 2021Cochise County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Jul 18, 2021, 4:50 PM MST for Cochise County, Arizona. It was in force for 40 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 18, 2021, 4:50 PM MST (23:50 UTC)
Expired: Jul 18, 2021, 5:30 PM MST
In force: 40 min
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Cochise County, AZ

The radar

The Tucson radar (KEMX), 69 km from the middle of the area, began a volume at 23:53 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

Tuscon, AZ (KTUS), launched 12:00Z, 11.8 hours before the alert went out and 100 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: 1146 J/kg
Mixed-layer CIN: -124 J/kg
Mixed-layer LCL: 1485 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

942 
WUUS55 KTWC 182350
SVRTWC
AZC003-190030-
/O.NEW.KTWC.SV.W.0069.210718T2350Z-210719T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tucson AZ
450 PM MST Sun Jul 18 2021

The National Weather Service in Tucson has issued a

* Severe Thunderstorm Warning for...
  Northwestern Cochise County in southeastern Arizona...

* Until 530 PM MST.

* At 449 PM MST, a severe thunderstorm was located near
  Pearce-Sunsites, or 24 miles south of Willcox, moving northwest at
  20 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Tombstone, Dragoon, Pearce-Sunsites and Cochise. 

This includes the following highways...
 Route 80 between mile markers 312 and 321.
 Route 82 near mile marker 67.
 Route 191 between mile markers 38 and 65.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Damaging winds and frequent 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.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3192 10965 3166 10991 3167 11008 3194 11021
      3221 10988
TIME...MOT...LOC 2349Z 135DEG 18KT 3191 10989 

HAIL...<.75IN
WIND...60MPH
 
$$

Cerniglia

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 6:50 PM MST	Special Weather Statement	TWC	Cochise	25 min
Jul 17, 8:04 PM MST	Special Weather Statement	TWC	Graham	41 min
Jul 17, 8:28 PM MST	Special Weather Statement	TWC	Cochise	32 min
Jul 18, 6:19 AM MST	Special Weather Statement	TWC	Santa Cruz	41 min
Jul 18, 7:55 AM MST	Areal Flood Advisory	TWC	Santa Cruz	3 hr
Jul 18, 11:57 AM MST	Areal Flood Advisory	TWC	Cochise	3 hr
Jul 18, 1:00 PM MST	Areal Flood Advisory	TWC	Graham	109 min
Jul 18, 1:28 PM MST	Flash Flood Watch	TWC	Cochise, Graham, Greenlee, Pima, Pinal, Santa Cruz	11 hr
Jul 18, 2:36 PM MST	Areal Flood Advisory	TWC	Graham	3 hr
Jul 18, 3:05 PM MST	Severe Thunderstorm Warning	TWC	Graham	40 min
Jul 18, 3:36 PM MST	Areal Flood Advisory	TWC	Graham	114 min
Jul 18, 4:08 PM MST	Flash Flood Warning Considerable damage threat	TWC	Greenlee	112 min
Jul 18, 4:10 PM MST	Special Weather Statement	TWC		35 min
Jul 18, 4:16 PM MST	Areal Flood Advisory	TWC	Graham, Greenlee	119 min
Jul 18, 4:21 PM MST	Areal Flood Advisory	TWC	Graham	114 min
Jul 18, 4:36 PM MST	Flash Flood Warning Considerable damage threat	TWC	Graham, Greenlee	3 hr
Jul 18, 4:45 PM MST	Areal Flood Advisory	TWC	Cochise	2 hr
Jul 18, 4:58 PM MST	Flash Flood Warning Considerable damage threat	TWC	Cochise	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.