Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 80, NWS Tucson, AZ

July 20, 2021Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Jul 20, 2021, 8:46 PM MST for Pima County, Arizona. It was in force for 30 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 20, 2021, 8:46 PM MST (03:46 UTC)
Expired: Jul 20, 2021, 9:16 PM MST
In force: 30 min
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Pima County, AZ

The radar

The Tucson radar (KEMX), 61 km from the middle of the area, began a volume at 03:54 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 00:00Z, 3.8 hours before the alert went out and 35 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: 712 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 2745 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: 49 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

153 
WUUS55 KTWC 210346
SVRTWC
AZC019-210445-
/O.NEW.KTWC.SV.W.0080.210721T0346Z-210721T0445Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tucson AZ
846 PM MST Tue Jul 20 2021

The National Weather Service in Tucson has issued a

* Severe Thunderstorm Warning for...
  Northeastern Pima County in southeastern Arizona...

* Until 945 PM MST.

* At 845 PM MST, a severe thunderstorm was located near Mount
  Lemmon/Summerhaven, or 11 miles southeast of Oracle, moving west 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...
  Catalina, Mount Lemmon/Summerhaven, Sabino Canyon Recreation Area,
  Catalina Foothills and Seven Falls.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3251 11058 3237 11059 3229 11090 3251 11091
TIME...MOT...LOC 0345Z 090DEG 8KT 3247 11068 

HAIL...1.00IN
WIND...60MPH
 
$$

Meyer

1 follow-up statement

792 
WWUS55 KTWC 210416
SVSTWC

Severe Weather Statement
National Weather Service Tucson AZ
916 PM MST Tue Jul 20 2021

AZC019-210425-
/O.CAN.KTWC.SV.W.0080.000000T0000Z-210721T0445Z/
Pima-
916 PM MST Tue Jul 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN PIMA COUNTY IS
CANCELLED...
        
The storm which prompted the warning near Summerhaven and the 
Catalinas has weakened below severe limits, and has exited west of 
the warned area. Therefore, the warning has been cancelled. However 
heavy rain is still possible with this thunderstorm.

LAT...LON 3251 11058 3237 11059 3229 11090 3251 11091
TIME...MOT...LOC 0406Z 090DEG 8KT 3247 11076 

$$

Meyer

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 6:00 PM MST	Areal Flood Advisory	TWC	Pima	3 hr
Jul 20, 6:44 PM MST	Special Weather Statement	TWC		46 min
Jul 20, 7:17 PM MST	Special Weather Statement	TWC	Santa Cruz	43 min
Jul 20, 8:02 PM MST	Severe Thunderstorm Warning	TWC	Pinal	58 min
Jul 20, 8:14 PM MST	Special Weather Statement	TWC		61 min
Jul 20, 8:17 PM MST	Severe Thunderstorm Warning	TWC	Pima	58 min
Jul 20, 8:40 PM MST	Areal Flood Advisory	TWC	Pima	2 hr
Jul 20, 9:13 PM MST	Special Weather Statement	TWC		62 min
Jul 20, 9:24 PM MST	Severe Thunderstorm Warning	TWC	Pima, Pinal	51 min
Jul 20, 9:42 PM MST	Areal Flood Advisory	TWC	Pima, Pinal	2 hr
Jul 20, 9:53 PM MST	Severe Thunderstorm Warning	TWC	Pinal	52 min
Jul 21, 1:50 AM MST	Flash Flood Watch	TWC	Cochise, Graham, Greenlee, Pima, Pinal, Santa Cruz	5 days
Jul 21, 8:18 AM MST	Blowing Dust Advisory	TWC	Pima, Pinal	8 hr
Jul 21, 1:00 PM MST	Special Weather Statement	TWC	Pima	45 min
Jul 21, 1:12 PM MST	Severe Thunderstorm Warning	TWC	Pima	48 min
Jul 21, 1:38 PM MST	Flash Flood Warning Considerable damage threat	TWC	Pima	3 hr
Jul 21, 1:57 PM MST	Special Weather Statement	TWC	Pima	48 min
Jul 21, 2:09 PM MST	Special Weather Statement	TWC	Pima	51 min
Jul 21, 2:16 PM MST	Severe Thunderstorm Warning	TWC	Pima	44 min
Jul 21, 2:21 PM MST	Dust Storm Advisory	TWC	Pima, Pinal	84 min
Jul 21, 2:51 PM MST	Areal Flood Advisory	TWC	Pima	3 hr
Jul 21, 3:01 PM MST	Dust Storm Warning	TWC	Pinal	32 min

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.