Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 128, NWS Tucson, AZ

August 14, 2021Santa Cruz County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 14, 2021, 3:23 PM MST for Santa Cruz 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
Aug 14, 2021, 3:23 PM MST (22:23 UTC)
Expired
Aug 14, 2021, 5:45 PM MST
In force
2 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 66 km from the middle of the area, began a volume at 22:23 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, 10.4 hours before the alert went out and 89 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 2021-08-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 69 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 2021-08-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -25 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
69 J/kg
Mixed-layer CIN
-61 J/kg
Mixed-layer LCL
788 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-25 m²/s²
0-3 km storm-relative helicity
66 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

206 
WGUS55 KTWC 142223
FFWTWC
AZC023-150045-
/O.NEW.KTWC.FF.W.0128.210814T2223Z-210815T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
323 PM MST Sat Aug 14 2021

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  South Central Santa Cruz County in southeastern Arizona...

* Until 545 PM MST.

* At 323 PM MST, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 2 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly. Flooding of the Nogales wash will be 
  likely.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Nogales, especially the Nogales wash.

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.

Remain alert for flooding even in locations not receiving rain. 
Washes, streams, and rivers can become raging killer currents in a 
matter of minutes, even from distant rainfall.

&&

LAT...LON 3133 11097 3136 11096 3142 11098 3145 11095
      3136 11091 3133 11091

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

JD
2 follow-up statements
856 
WGUS75 KTWC 142321
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
421 PM MST Sat Aug 14 2021

AZC023-150045-
/O.CON.KTWC.FF.W.0128.000000T0000Z-210815T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Santa Cruz AZ-
421 PM MST Sat Aug 14 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM MST THIS 
AFTERNOON FOR SOUTH CENTRAL SANTA CRUZ COUNTY...

At 421 PM MST, Although the heavy rainfall had ended, flooding is 
ongoing in the area. The Nogales wash was also showing signs of the 
water receding as of 420 pm mst.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Nogales and the Nogales wash.

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.

Remain alert for flooding even in locations not receiving rain. 
Washes, streams, and rivers can become raging killer currents in a 
matter of minutes, even from distant rainfall.

&&

LAT...LON 3133 11097 3136 11096 3142 11098 3145 11095
      3136 11091 3133 11091

FLASH FLOOD...RADAR INDICATED

$$

JD
744 
WGUS75 KTWC 150037
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
537 PM MST Sat Aug 14 2021

AZC023-150047-
/O.EXP.KTWC.FF.W.0128.000000T0000Z-210815T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Santa Cruz AZ-
537 PM MST Sat Aug 14 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 545 PM MST THIS AFTERNOON FOR 
SOUTH CENTRAL SANTA CRUZ COUNTY...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

A Flash Flood Watch remains in effect until 500 PM MST Sunday for a 
portion of Southeast Arizona.

LAT...LON 3133 11097 3136 11096 3142 11098 3145 11095
      3136 11091 3133 11091

$$

JD

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 13, 5:06 PM MSTSpecial Weather StatementTWCCochise39 min
Aug 13, 5:07 PM MSTFlash Flood Warning Considerable damage threatTWCGraham, Greenlee3 hr
Aug 13, 5:11 PM MSTFlash Flood Warning Considerable damage threatTWCCochise3 hr
Aug 13, 5:48 PM MSTSpecial Weather StatementTWCCochise42 min
Aug 13, 6:05 PM MSTSevere Thunderstorm WarningTWCCochise40 min
Aug 13, 6:08 PM MSTSpecial Weather StatementTWC37 min
Aug 13, 6:12 PM MSTSpecial Weather StatementTWC48 min
Aug 13, 6:26 PM MSTFlash Flood Warning Considerable damage threatTWCCochise, Graham3 hr
Aug 13, 6:30 PM MSTFlash Flood Warning Considerable damage threatTWCCochise3 hr
Aug 13, 6:35 PM MSTAreal Flood AdvisoryTWCPima115 min
Aug 13, 6:40 PM MSTSevere Thunderstorm WarningTWCCochise, Pima, Santa Cruz50 min
Aug 13, 7:04 PM MSTSpecial Weather StatementTWCCochise41 min
Aug 13, 7:22 PM MSTSpecial Weather StatementTWCSanta Cruz38 min
Aug 13, 7:55 PM MSTSpecial Weather StatementTWCSanta Cruz65 min
Aug 13, 11:49 PM MSTDust Storm AdvisoryTWCPima, Pinal56 min
Aug 14, 12:54 AM MSTAreal Flood AdvisoryTWCPima, Pinal3 hr
Aug 14, 1:02 AM MSTAreal Flood AdvisoryTWCPinal3 hr
Aug 14, 1:58 AM MSTSpecial Weather StatementTWC62 min
Aug 14, 4:11 AM MSTAreal Flood AdvisoryTWCPima4 hr
Aug 14, 5:06 AM MSTFlash Flood WarningTWCPima3 hr
Aug 14, 5:35 AM MSTAreal Flood AdvisoryTWCPima3 hr
Aug 14, 1:53 PM MSTAreal Flood AdvisoryTWCPinal112 min
Aug 14, 2:19 PM MSTFlash Flood Warning Considerable damage threatTWCPinal116 min
Aug 14, 2:53 PM MSTAreal Flood AdvisoryTWCSanta Cruz3 hr
Aug 14, 3:19 PM MSTAreal Flood AdvisoryTWCPima3 hr
Aug 14, 3:23 PM MSTAreal Flood AdvisoryTWCPima3 hr
Aug 14, 3:25 PM MSTFlash Flood Warning Considerable damage threatTWCCochise3 hr
Aug 14, 3:28 PM MSTAreal Flood AdvisoryTWCPinal3 hr
Aug 14, 3:56 PM MSTSpecial Weather StatementTWCCochise49 min
Aug 14, 4:01 PM MSTFlash Flood Warning Considerable damage threatTWCCochise3 hr
Aug 14, 4:05 PM MSTFlash Flood Warning Considerable damage threatTWCPima115 min
Aug 14, 4:18 PM MSTAreal Flood AdvisoryTWCCochise3 hr
Aug 14, 4:36 PM MSTAreal Flood AdvisoryTWCPima114 min
Aug 14, 4:40 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.