Tornadoes · United States · Arizona · 2019
EF0 tornado, Shopishk, Arizona, September 16, 2019
This EF0 tornado ran 0.1 miles across Pinal County on September 16, 2019, touching down at 1:55 PM MST and reaching 10 yards wide. It killed nobody.
The rating scale
Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
EF2111 to 135 mph
Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.
EF3136 to 165 mph
Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
EF5over 200 mph
Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.
Unrated
The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.
The record
- Rating
- EF0
- Date
- September 16, 2019
- Touchdown
- 1:55 PM MST (20:55 UTC)
- Path length
- 0.1 miles (0.2 km)
- Path width
- 10 yards (9 m)
- Deaths
- 0
- Injuries
- 0
- County
- Pinal County
- Touchdown point
- 32.700, -111.840
- Lift-off point
- 32.700, -111.840
- Record number
- 1909161455-01
What the Weather Service recorded
Scattered thunderstorms moved east across Pima and Pinal counties during the afternoon and evening. Storms formed a haboob in Pinal County and caused wind damage in Eloy. Flash flooding was also reported in Chuichu and Picture Rocks. A landspout tornado formed south of Chuichu.
Landspout tornado developed in remote terrain to the south of Chuichu ahead of developing thunderstorms.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 20:49 UTC | 21:30 UTC | Dust Storm Warning | PSR |
| 20:52 UTC | 21:30 UTC | Severe Thunderstorm Warning | TWC |
| 20:52 UTC | 21:30 UTC | Severe Thunderstorm Warning | TWC |
| 20:54 UTC | 22:00 UTC | Dust Storm Warning | TWC |
| 20:56 UTC | 21:45 UTC | Severe Thunderstorm Warning | PSR |
| 21:17 UTC | 22:00 UTC | Severe Thunderstorm Warning | TWC |
| 21:21 UTC | 22:45 UTC | Flood Advisory | TWC |
| 21:25 UTC | 22:15 UTC | Dust Storm Warning | PSR |
| 21:27 UTC | 22:15 UTC | Severe Thunderstorm Warning | TWC |
| 21:47 UTC | 23:45 UTC | Flash Flood Warning | TWC |
| 22:11 UTC | 22:45 UTC | Dust Storm Advisory | PSR |
| 22:43 UTC | 01:45 UTC | Flood Advisory | TWC |
| 23:29 UTC | 00:15 UTC | Severe Thunderstorm Warning | TWC |
| 00:33 UTC | 03:30 UTC | Flood Advisory | PSR |
Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.
The forecast that day
The Storm Prediction Center had this point in a General Thunderstorms Risk. The outlook in force was issued at 19:48 UTC.
SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.
The air that afternoon
The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.
Phoenix, AZ (KPSR), 12:00Z
8.9 hours before the tornado, 82 km from the path. September 16, 2019.
- Mixed-layer CAPE
- 436 J/kg
- Mixed-layer CIN
- -185 J/kg
- Surface CAPE
- 97 J/kg
- Mixed-layer LCL
- 2091 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 56 m²/s²
- 0-3 km storm-relative helicity
- 98 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
- 0-3 km lapse rate
- 6.8 K/km
Phoenix, AZ (KPSR), 00:00Z
3.1 hours after it, 82 km from the path. September 17, 2019.
- Mixed-layer CAPE
- 1485 J/kg
- Mixed-layer CIN
- -2 J/kg
- Surface CAPE
- 1622 J/kg
- Mixed-layer LCL
- 2481 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km bulk shear
- 2 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 38 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
- 0-3 km lapse rate
- 9.2 K/km
The surface observations
Casa Granda (Awos) (CGZ), 29 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 18:55 UTC | 240° 5 kt | 1013.2 | ||||
| 18:56 UTC | 95 | 62 | 250° 5 kt | 1013.2 | ||
| 19:00 UTC | 0° 0 kt | 1013.2 | ||||
| 19:05 UTC | 140° 7 kt | 1013.2 | ||||
| 19:10 UTC | 0° 0 kt | 1013.2 | ||||
| 19:15 UTC | 140° 4 kt | 1012.9 | ||||
| 19:20 UTC | 110° 2 kt | 1012.9 | ||||
| 19:25 UTC | 90° 4 kt | 1012.9 | ||||
| 19:30 UTC | 90° 7 kt | 1012.5 | ||||
| 19:35 UTC | 80° 2 kt | 1012.5 | ||||
| 19:40 UTC | 70° 5 kt | 1012.5 | ||||
| 19:45 UTC | 80° 8 kt | 1012.2 | ||||
| 19:50 UTC | 60° 8 kt | 1012.2 | ||||
| 19:55 UTC | 80° 7 kt | 1012.2 | ||||
| 19:56 UTC | 96 | 62 | 5 kt | 1012.2 | ||
| 20:00 UTC | 130° 5 kt | 1011.9 | ||||
| 20:05 UTC | 10° 5 kt | 1011.9 | ||||
| 20:10 UTC | 80° 7 kt | 1011.9 | ||||
| 20:15 UTC | 90° 5 kt | 1011.5 | ||||
| 20:20 UTC | 200° 2 kt | 1011.5 | ||||
| 20:25 UTC | 0° 0 kt | 1011.5 | ||||
| 20:30 UTC | 320° 5 kt | 1011.2 | ||||
| 20:35 UTC | 310° 8 kt | 1010.8 | ||||
| 20:40 UTC | 310° 5 kt | 1010.8 | ||||
| 20:45 UTC | 280° 11 kt | 1010.8 | ||||
| 20:50 UTC | 10 kt | 1011.2 | ||||
| 20:55 UTC | 300° 11 kt | 1010.8 | ||||
| 20:56 UTC | 96 | 61 | 290° 11 kt | 1010.8 | ||
| 21:00 UTC | 300° 10 kt | 1010.8 | ||||
| 21:05 UTC | 270° 10 kt | 1010.8 | -RA | |||
| 21:10 UTC | 290° 9 kt | 1010.8 | -RA | |||
| 21:15 UTC | 280° 10 kt | 1010.5 | -RA | |||
| 21:20 UTC | 270° 8 kt | 1010.8 | -RA | |||
| 21:25 UTC | 290° 5 kt | 1010.8 | -RA | |||
| 21:30 UTC | 280° 5 kt | 1011.2 | ||||
| 21:34 UTC | 93.2 | 62.6 | 260° 6 kt | 1011.5 | VCTS -RA | |
| 21:35 UTC | 240° 5 kt | 1011.5 | -RA | |||
| 21:40 UTC | 11 kt | 1011.9 | -RA | |||
| 21:45 UTC | 200° 8 kt | 1011.5 | -RA | |||
| 21:50 UTC | 9 kt | 1011.5 | -RA | |||
| 21:55 UTC | 190° 10 kt | 1011.9 | -RA | |||
| 21:56 UTC | 85 | 63 | 180° 12 kt | 16 | 1011.9 | VCTS -RA |
| 22:00 UTC | 17 kt | 1012.2 | -RA | |||
| 22:05 UTC | 17 kt | 1012.2 | -RA | |||
| 22:10 UTC | 160° 21 kt | 1011.9 | -RA | |||
| 22:15 UTC | 150° 15 kt | 1011.5 | -RA | |||
| 22:20 UTC | 19 kt | 1011.2 | -RA | |||
| 22:21 UTC | 80.6 | 62.6 | 150° 18 kt | 29 | 1011.2 | -RA |
| 22:25 UTC | 16 kt | 1010.8 | -RA | |||
| 22:30 UTC | 18 kt | 1010.5 | -RA | |||
| 22:35 UTC | 17 kt | 1010.5 | ||||
| 22:40 UTC | 16 kt | 1010.5 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Phoenix radar (KIWA), 67 km away, was scanning. The volume nearest the touchdown began at 20:56 UTC.
Open the radar archive at this moment, over the track
Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 19:26 UTC | TORNADO | 4 Sw Chuichu | Pinal, AZ | CORRECTS PREVIOUS TORNADO REPORT FROM 4 SW CHUICHU. LANDSPOUT TORNADO DEVELOPED IN REMOTE TERRAIN SOUTH OF CHUICHU AHEAD OF DEVELOPING THUNDERSTORMS. NO DAMAGE REPORTED. LOCATION BASED ON STORM SPOTTER REPORTS FROM SOCIA |
| 20:55 UTC | TORNADO | 4 Sw Chuichu | Pinal, AZ | CORRECTS TIME FROM PREVIOUS TORNADO REPORT FROM 4 SW CHUICHU. LANDSPOUT TORNADO DEVELOPED IN REMOTE TERRAIN SOUTH OF CHUICHU AHEAD OF DEVELOPING THUNDERSTORMS. NO DAMAGE REPORTED. LOCATION BASED ON STORM SPOTTER REPORTS |
| 20:59 UTC | TSTM WND DMG | 1 Ne Chuichu | Pinal, AZ | ROOF BLOWN OFF MOBILE HOME AND INTO THE POWERLINES. TIME ESTIMATED BASED ON RADAR. |
| 21:07 UTC | DUST STORM | Eloy | Pinal, AZ | WALL OF DUST SEEN IN MANY PICTURES AND VIDEOS FROM SPOTTERS AND CHASERS IN THE ELOY AREA. VISIBILITY BELOW ONE QUARTER OF A MILE. TIMES ESTIMATED FROM RADAR AND REPORTS. |
| 21:12 UTC | DUST STORM | 1 Ne Arizona City | Pinal, AZ | BLOWING DUST WITH VISIBILITY DOWN TO 200 FT. |
| 21:16 UTC | DUST STORM | 5 Nne Arizona City | Pinal, AZ | VISIBILITY 1/4 MILE IN DENSE BLOWING DUST. |
| 21:35 UTC | TSTM WND DMG | Eloy | Pinal, AZ | STRUCTURAL DAMAGE TO AZTEC TIRES IN ELOY. TIME ESTIMATED BASED ON RADAR. |
| 21:53 UTC | FLASH FLOOD | 1 Ne Chuichu | Pinal, AZ | FLASH FLOOD DAMAGE, EXTENT UNKNOWN. TIME ESTIMATED BASED ON RADAR. |
| 21:55 UTC | TSTM WND GST 41 | 7 Ese Coolidge | Pinal, AZ | *DELAYED REPORT* WITH 3/4 MILE VISIBILITY IN BLOWING DUST. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2019 tornado in ArizonaEvery tornado in Arizona since 1950Warnings in force in Arizona nowThe forecast where you are
What this means
Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.