Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 6, NWS Tucson, AZ

July 3, 2021Pima County, Santa Cruz County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 3, 2021, 12:17 PM MST for Pima County, Santa Cruz County, Arizona. It was in force for 3 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
Jul 3, 2021, 12:17 PM MST (19:17 UTC)
Expired
Jul 3, 2021, 3:08 PM MST
In force
3 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

Counties Pima County, AZ, Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 56 km from the middle of the area, began a volume at 19:18 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, 7.3 hours before the alert went out and 51 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-pSkew-T log-p diagram, Tuscon, AZ at 12:00Z on 2021-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 278 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 12:00Z on 2021-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -64 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
278 J/kg
Mixed-layer CIN
-96 J/kg
Mixed-layer LCL
1669 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-64 m²/s²
0-3 km storm-relative helicity
-2 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

012 
WGUS55 KTWC 031917
FFWTWC
AZC019-023-032215-
/O.NEW.KTWC.FF.W.0006.210703T1917Z-210703T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
1217 PM MST Sat Jul 3 2021

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  Southeastern Pima County in southeastern Arizona...
  Northwestern Santa Cruz County in southeastern Arizona...

* Until 315 PM MST.

* At 1217 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Green Valley, Amado and Arivaca Junction.

This includes the following streams and drainages...
  South Mendoza Wash, Peñitas Wash, Sopori Wash, Demetrie Wash, 
  Little Thomas Wash, Puertocito Wash, Brawley Wash, Bolas Blancas 
  Wash, Arroyo Seco, Thomas Canyon Wash, Champurrado Wash, Soto 
  Wash, Santa Cruz River, Old Junction Wash, Santa Margarita Wash, 
  Las Guijas Wash, Brown Wash, Cerro Prieto Wash, Altar Wash, Banner 
  Wash, Saucito Wash and Arivaca Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 3165 11125 3165 11150 3175 11149 3182 11145
      3184 11141 3189 11131 3197 11128 3199 11118
      3202 11107 3196 11100 3188 11107 3177 11109
      3173 11107 3172 11106 3168 11107 3165 11110

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

$$

JM
2 follow-up statements
465 
WGUS75 KTWC 032022
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
122 PM MST Sat Jul 3 2021

AZC019-023-032215-
/O.CON.KTWC.FF.W.0006.000000T0000Z-210703T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-Santa Cruz AZ-
122 PM MST Sat Jul 3 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 315 PM MST THIS 
AFTERNOON FOR SOUTHEASTERN PIMA AND NORTHWESTERN SANTA CRUZ 
COUNTIES...

At 122 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1 and 3 inches of rain have 
fallen. Additional rainfall amounts of 0.1 to 0.5 inches are 
possible in the warned area. Flash flooding is ongoing or expected 
to begin shortly.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Green Valley, Amado and Arivaca Junction.

This includes the following streams and drainages...
  South Mendoza Wash, Peñitas Wash, Sopori Wash, Demetrie Wash, 
  Little Thomas Wash, Puertocito Wash, Brawley Wash, Bolas Blancas 
  Wash, Arroyo Seco, Thomas Canyon Wash, Champurrado Wash, Soto 
  Wash, Santa Cruz River, Old Junction Wash, Santa Margarita Wash, 
  Las Guijas Wash, Brown Wash, Cerro Prieto Wash, Altar Wash, Banner 
  Wash, Saucito Wash and Arivaca Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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



&&

LAT...LON 3165 11125 3165 11150 3175 11149 3182 11145
      3184 11141 3189 11131 3197 11128 3199 11118
      3202 11107 3196 11100 3188 11107 3177 11109
      3173 11107 3172 11106 3168 11107 3165 11110

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

$$

JM
331 
WGUS75 KTWC 032208
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
308 PM MST Sat Jul 3 2021

AZC019-023-032218-
/O.CAN.KTWC.FF.W.0006.000000T0000Z-210703T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-Santa Cruz AZ-
308 PM MST Sat Jul 3 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN PIMA AND 
NORTHWESTERN SANTA CRUZ COUNTIES...

The heavy rain has ended. Flash flooding is no longer expected to 
pose a threat. However minor flows in area washes will continue into 
early evening. Please continue to heed remaining road closures.

LAT...LON 3165 11125 3165 11150 3175 11149 3182 11145
      3184 11141 3189 11131 3197 11128 3199 11118
      3202 11107 3196 11100 3188 11107 3177 11109
      3173 11107 3172 11106 3168 11107 3165 11110

$$

JM

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 2, 5:17 PM MSTSpecial Weather StatementTWCPinal43 min
Jul 2, 5:31 PM MSTSpecial Weather StatementTWC44 min
Jul 2, 5:35 PM MSTSevere Thunderstorm WarningTWCCochise, Pima40 min
Jul 2, 6:14 PM MSTSpecial Weather StatementTWC46 min
Jul 2, 6:16 PM MSTSpecial Weather StatementTWCPima29 min
Jul 2, 6:16 PM MSTSevere Thunderstorm WarningTWCCochise, Pima44 min
Jul 2, 7:13 PM MSTSevere Thunderstorm WarningTWCPima47 min
Jul 2, 7:34 PM MSTAreal Flood AdvisoryTWCPima, Pinal116 min
Jul 3, 11:17 AM MSTAreal Flood AdvisoryTWCCochise, Santa Cruz3 hr
Jul 3, 11:21 AM MSTSevere Thunderstorm WarningTWCSanta Cruz39 min
Jul 3, 11:51 AM MSTSpecial Weather StatementTWCPima54 min
Jul 3, 11:58 AM MSTFlash Flood Warning Considerable damage threatTWCCochise, Santa Cruz3 hr
Jul 3, 12:09 PM MSTAreal Flood AdvisoryTWCPima, Santa Cruz111 min
Jul 3, 12:23 PM MSTSevere Thunderstorm WarningTWCCochise, Santa Cruz35 min
Jul 3, 12:28 PM MSTFlash Flood Warning Considerable damage threatTWCCochise, Pima, Santa Cruz3 hr
Jul 3, 1:07 PM MSTFlash Flood Warning Considerable damage threatTWCPima3 hr
Jul 3, 1:15 PM MSTSpecial Weather StatementTWCPima45 min
Jul 3, 1:20 PM MSTSpecial Weather StatementTWCPima40 min
Jul 3, 1:50 PM MSTSevere Thunderstorm WarningTWCCochise, Pima40 min
Jul 3, 2:14 PM MSTSpecial Weather StatementTWC31 min
Jul 3, 2:56 PM MSTSpecial Weather StatementTWCPima34 min
Jul 3, 3:31 PM MSTSpecial Weather StatementTWCPinal44 min
Jul 3, 3:44 PM MSTAreal Flood AdvisoryTWCPima2 hr

Nearby

Flash Flood Warnings in Arizona, 2021Every 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.