Alert archive / Arizona / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 198, NWS Tucson, AZ

September 29, 2021Pinal County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Sep 29, 2021, 11:57 PM MST for Pinal County, Arizona. It was in force for 48 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: Sep 29, 2021, 11:57 PM MST (06:57 UTC)
Expired: Sep 30, 2021, 12:45 AM MST
In force: 48 min
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Pinal County, AZ

The radar

The Phoenix radar (KIWA), 62 km from the middle of the area, began a volume at 06:59 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, 7.0 hours before the alert went out and 91 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: 314 J/kg
Mixed-layer CIN: -91 J/kg
Mixed-layer LCL: 2898 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 31 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

263 
WUUS55 KTWC 300657
SVRTWC
AZC021-300745-
/O.NEW.KTWC.SV.W.0198.210930T0657Z-210930T0745Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tucson AZ
1157 PM MST Wed Sep 29 2021

The National Weather Service in Tucson has issued a

* Severe Thunderstorm Warning for...
  North central Pinal County in southeastern Arizona...

* Until 1245 AM MST.

* At 1157 PM MST, a severe thunderstorm was located near Florence,
  moving east at 25 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...
  Cactus Forest and Kelvin. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3291 11093 3286 11137 3293 11141 3323 11098
TIME...MOT...LOC 0657Z 252DEG 21KT 3301 11128 

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

$$

RH

1 follow-up statement

711 
WWUS55 KTWC 300715
SVSTWC

Severe Weather Statement
National Weather Service Tucson AZ
1215 AM MST Thu Sep 30 2021

AZC021-300745-
/O.CON.KTWC.SV.W.0198.000000T0000Z-210930T0745Z/
Pinal-
1215 AM MST Thu Sep 30 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1245 AM MST
FOR NORTH CENTRAL PINAL COUNTY...

At 1214 AM MST, a severe thunderstorm was located 11 miles east of
Florence, moving east at 25 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...
Kelvin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3287 11131 3300 11131 3323 11098 3291 11093
TIME...MOT...LOC 0714Z 252DEG 21KT 3304 11116 

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

$$

RH

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 29, 11:08 PM MST	Flash Flood Warning Considerable damage threat	TWC	Pima	112 min
Sep 29, 11:25 PM MST	Areal Flood Advisory	TWC	Pima	3 hr
Sep 29, 11:51 PM MST	Flash Flood Warning	TWC	Pima	3 hr
Sep 30, 12:13 AM MST	Severe Thunderstorm Warning	TWC	Pima	47 min
Sep 30, 12:24 AM MST	Areal Flood Advisory	TWC	Pima, Pinal	3 hr
Sep 30, 12:40 AM MST	Severe Thunderstorm Warning	TWC	Pinal	50 min
Sep 30, 12:57 AM MST	Special Weather Statement	TWC	Pinal	33 min
Sep 30, 3:21 AM MST	Special Weather Statement	TWC		39 min
Sep 30, 4:05 AM MST	Areal Flood Advisory	TWC	Cochise	115 min
Sep 30, 12:58 PM MST	Special Weather Statement	TWC	Santa Cruz	47 min
Sep 30, 2:23 PM MST	Areal Flood Advisory	TWC	Cochise	97 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.