Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 133, NWS Tucson, AZ

August 16, 2021Pinal County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 16, 2021, 1:49 PM MST for Pinal 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
Aug 16, 2021, 1:49 PM MST (20:49 UTC)
Expired
Aug 16, 2021, 5:00 PM MST
In force
3 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Pinal County, AZ

The radar

The Phoenix radar (KIWA), 98 km from the middle of the area, began a volume at 20:50 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, 8.8 hours before the alert went out and 68 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 2021-08-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1291 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 2021-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 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
1291 J/kg
Mixed-layer CIN
-54 J/kg
Mixed-layer LCL
1297 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

674 
WGUS55 KTWC 162049
FFWTWC
AZC021-170000-
/O.NEW.KTWC.FF.W.0133.210816T2049Z-210817T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
149 PM MST Mon Aug 16 2021

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  East Central Pinal County in southeastern Arizona...

* Until 500 PM MST.

* At 149 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen with isolated areas up to 3 inches. Additional 
  rainfall amounts up to 1 inch 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...
  Dudleyville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3268 11088 3278 11091 3287 11089 3287 11079
      3285 11072 3283 11071 3268 11074

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

$$

AH
2 follow-up statements
977 
WGUS75 KTWC 162152
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
252 PM MST Mon Aug 16 2021

AZC021-170000-
/O.CON.KTWC.FF.W.0133.000000T0000Z-210817T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pinal AZ-
252 PM MST Mon Aug 16 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS 
AFTERNOON FOR EAST CENTRAL PINAL COUNTY...

At 252 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1 and 3 inches of rain have 
fallen. 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...
  Dudleyville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3268 11088 3278 11091 3287 11089 3287 11079
      3285 11072 3283 11071 3268 11074

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

$$

AH
444 
WGUS75 KTWC 162354
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
454 PM MST Mon Aug 16 2021

AZC021-170004-
/O.EXP.KTWC.FF.W.0133.000000T0000Z-210817T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pinal AZ-
454 PM MST Mon Aug 16 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 5 PM MST THIS AFTERNOON FOR 
EAST CENTRAL PINAL COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Flows will continue in area washes into the evening. Please 
continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 200 AM MST Tuesday for a 
portion of Southeast Arizona.

LAT...LON 3268 11088 3278 11091 3287 11089 3287 11079
      3285 11072 3283 11071 3268 11074

$$

JRM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 7:02 PM MSTSpecial Weather StatementTWCGreenlee43 min
Aug 15, 7:47 PM MSTSpecial Weather StatementTWCGraham58 min
Aug 15, 8:30 PM MSTSevere Thunderstorm WarningTWCGraham, Pinal46 min
Aug 16, 12:20 PM MSTSevere Thunderstorm WarningTWCPinal55 min
Aug 16, 12:39 PM MSTFlash Flood Warning Considerable damage threatTWCPinal3 hr
Aug 16, 1:27 PM MSTSevere Thunderstorm WarningTWCPinal48 min
Aug 16, 3:06 PM MSTAreal Flood AdvisoryTWCGraham, Greenlee3 hr
Aug 16, 3:11 PM MSTSpecial Weather StatementTWCSanta Cruz34 min
Aug 16, 3:14 PM MSTSpecial Weather StatementTWCGraham46 min
Aug 16, 3:58 PM MSTSpecial Weather StatementTWCGraham47 min
Aug 16, 4:38 PM MSTAreal Flood AdvisoryTWCGraham, Greenlee3 hr
Aug 16, 4:44 PM MSTSevere Thunderstorm WarningTWCGraham46 min

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.