Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Tucson, AZ

June 30, 2021Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jun 30, 2021, 1:29 PM MST for Pima County, Arizona. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 30, 2021, 1:29 PM MST (20:29 UTC)
Expired: Jun 30, 2021, 3:30 PM MST
In force: 2 hr
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Pima County, AZ

The radar

The Tucson radar (KEMX), 63 km from the middle of the area, began a volume at 20:29 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, 8.5 hours before the alert went out and 28 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: 383 J/kg
Mixed-layer CIN: -164 J/kg
Mixed-layer LCL: 1900 m above ground
0-6 km bulk shear: 4 kt
0-1 km storm-relative helicity: -22 m²/s²
0-3 km storm-relative helicity: 6 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

612 
WGUS55 KTWC 302029
FFWTWC
AZC019-302230-
/O.NEW.KTWC.FF.W.0001.210630T2029Z-210630T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
129 PM MST Wed Jun 30 2021

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  The Bighorn Burn Scar in...
  Northeastern Pima County in southeastern Arizona...

* Until 330 PM MST.

* At 129 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over the Bighorn Burn Scar. Up to 0.75 inch of rain has 
  fallen in the Sutherland Wash Basin. Flash flooding is ongoing or 
  expected to begin shortly.

Excessive rainfall over the burn scar will result in debris flow 
moving through the Pima Canyon, Finger Rock Canyon, Ventana Canyon, 
Sabino Canyon, Canada del Oro, and Sutherland Wash. The debris flow 
can consist of rock, mud, vegetation and other loose materials.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding in and around the Bighorn
           Burn Scar.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of areas in and around
           the Bighorn Burn Scar.

* Some locations that will experience flash flooding include...
  Catalina, Oro Valley, Casas Adobes, Catalina State Park and 
  Catalina Foothills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life threatening situation. Heavy rainfall will cause 
extensive and severe flash flooding of creeks...streams...and 
ditches in the Bighorn Burn Scar. Severe debris flows can also be 
anticipated across roads. Roads and driveways may be washed away in 
places. If you encounter flood waters...climb to safety.

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3249 11088 3243 11093 3240 11094 3235 11096
      3232 11089 3233 11082 3238 11081 3247 11080
      3251 11085

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

GL

3 follow-up statements

145 
WGUS75 KTWC 302104
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
204 PM MST Wed Jun 30 2021

AZC019-302230-
/O.CON.KTWC.FF.W.0001.000000T0000Z-210630T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
204 PM MST Wed Jun 30 2021

...FLASH FLOOD WARNING FOR THE BIGHORN BURN SCAR REMAINS IN EFFECT 
UNTIL 330 PM MST THIS AFTERNOON FOR NORTHEASTERN PIMA COUNTY...

At 204 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain has started to taper off over the Bighorn Burn Scar. Radar 
estimates indicated localized rain amounts up to 1.5 inches have 
fallen in the Sutherland Wash Basin over the last hour. Flash 
flooding is ongoing or expected to begin shortly.

Excessive rainfall over the burn scar will result in debris flow 
moving through the Pima Canyon, Finger Rock Canyon, Ventana Canyon, 
Sabino Canyon, Canada del Oro, and Sutherland Wash. The debris flow 
can consist of rock, mud, vegetation and other loose materials.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding in and around the Bighorn Burn Scar.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of areas in and around
         the Bighorn Burn Scar.

Some locations that will experience flash flooding include...
  Catalina, Oro Valley, Casas Adobes, Catalina State Park and 
  Catalina Foothills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life threatening situation. Heavy rainfall will cause 
extensive and severe flash flooding of creeks...streams...and 
ditches in the Bighorn Burn Scar. Severe debris flows can also be 
anticipated across roads. Roads and driveways may be washed away in 
places. If you encounter flood waters...climb to safety.

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3249 11088 3243 11093 3240 11094 3235 11096
      3232 11089 3233 11082 3238 11081 3247 11080
      3251 11085

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

GL

610 
WGUS75 KTWC 302147
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
247 PM MST Wed Jun 30 2021

AZC019-302230-
/O.CON.KTWC.FF.W.0001.000000T0000Z-210630T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
247 PM MST Wed Jun 30 2021

...FLASH FLOOD WARNING FOR THE BIGHORN BURN SCAR REMAINS IN EFFECT 
UNTIL 330 PM MST THIS AFTERNOON FOR NORTHEASTERN PIMA COUNTY...

At 247 PM MST, Doppler Radar and rainfall gages indicate that heavy 
rain has ended over the Bighorn Burn Scar. Up to 1.5 inches occurred 
in this region between about 1 PM MST and 2 PM MST. Flash flooding 
is likely ongoing, especially in the Sutherland Wash Basin.

Excessive rainfall over the burn scar will result in debris flow 
moving through the Pima Canyon, Finger Rock Canyon, Ventana Canyon, 
Sabino Canyon, Canada del Oro, and Sutherland Wash. The debris flow 
can consist of rock, mud, vegetation and other loose materials.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding in and around the Bighorn Burn Scar.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of areas in and around
         the Bighorn Burn Scar.

Some locations that will experience flash flooding include...
  Catalina, Oro Valley, Casas Adobes, Catalina State Park and 
  Catalina Foothills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life threatening situation. Heavy rainfall will cause 
extensive and severe flash flooding of creeks...streams...and 
ditches in the Bighorn Burn Scar. Severe debris flows can also be 
anticipated across roads. Roads and driveways may be washed away in 
places. If you encounter flood waters...climb to safety.

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3249 11088 3243 11093 3240 11094 3235 11096
      3232 11089 3233 11082 3238 11081 3247 11080
      3251 11085

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

GL

311 
WGUS75 KTWC 302226
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
326 PM MST Wed Jun 30 2021

AZC019-302236-
/O.EXP.KTWC.FF.W.0001.000000T0000Z-210630T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
326 PM MST Wed Jun 30 2021

...FLASH FLOOD WARNING FOR THE BIGHORN BURN SCAR WILL EXPIRE AT 330 
PM MST THIS AFTERNOON FOR NORTHEASTERN PIMA COUNTY...

Flow in washes has diminished. Flooding is no longer expected to 
pose a threat.

LAT...LON 3249 11088 3243 11093 3240 11094 3235 11096
      3232 11089 3233 11082 3238 11081 3247 11080
      3251 11085

$$

GL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 2:46 PM MST	Areal Flood Advisory	TWC	Pima	89 min
Jun 30, 4:57 PM MST	Areal Flood Advisory	TWC	Pinal	93 min

Nearby

Flash Flood Warnings in Arizona, 2021 Every flash flood 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.