Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 87, NWS Tucson, AZ

August 2, 2021Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 2, 2021, 8:14 PM MST for Pima County, Arizona. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 2, 2021, 8:14 PM MST (03:14 UTC)
Expired
Aug 2, 2021, 11:15 PM MST
In force
3 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), 21 km from the middle of the area, began a volume at 03:16 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.

What was reported inside it

TimeReportWhereRemark
Aug 2, 8:35 PM MSTFLASH FLOOD7 Ene Tucson, AZSWIFT WATER RESCUE OF 3 PEOPLE NEAR TANQUE VERDE WASH AND BONANZA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 00:00Z, 3.2 hours before the alert went out and 23 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 00:00Z on 2021-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1093 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 00:00Z on 2021-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 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
1093 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
2632 m above ground
0-6 km bulk shear
0 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
37 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

394 
WGUS55 KTWC 030314
FFWTWC
AZC019-030615-
/O.NEW.KTWC.FF.W.0087.210803T0314Z-210803T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
814 PM MST Mon Aug 2 2021

The National Weather Service in Tucson has issued a

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

* Until 1115 PM MST.

* At 814 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 with these latest 
  thunderstorms. This is on top of the rainfall earlier this 
  evening. Flash flooding is ongoing or expected to begin shortly. 
  This warning extends in area and time the previous Flash Flood 
  Warning for the east side of Tucson and replaces the Urban and 
  Small Stream Advisory for the Vail area.

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

  SOURCE...Radar and automated gauges.

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

* Some locations that will experience flash flooding include...
  Tucson, Davis-Monthan Air Force Base, Tanque Verde, Vail, Saguaro 
  National Park East, Corona De Tucson, Catalina Foothills and Rita 
  Ranch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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 3195 11052 3195 11070 3193 11070 3193 11083
      3226 11085 3231 11075 3226 11065 3216 11059

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

$$

GZ
1 follow-up statement
152 
WGUS75 KTWC 030624
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
1124 PM MST Mon Aug 2 2021

AZC019-030634-
/O.EXP.KTWC.FF.W.0087.000000T0000Z-210803T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
1124 PM MST Mon Aug 2 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR EAST CENTRAL PIMA 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.

LAT...LON 3195 11052 3195 11070 3193 11070 3193 11083
      3226 11085 3231 11075 3226 11065 3216 11059

$$

GL

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 5:15 PM MSTSpecial Weather StatementTWCSanta Cruz30 min
Aug 2, 5:19 PM MSTDust Storm AdvisoryTWCCochise41 min
Aug 2, 5:33 PM MSTSpecial Weather StatementTWC42 min
Aug 2, 5:48 PM MSTSpecial Weather StatementTWC42 min
Aug 2, 5:51 PM MSTAreal Flood AdvisoryTWCPima114 min
Aug 2, 5:58 PM MSTFlash Flood Warning Considerable damage threatTWCPima3 hr
Aug 2, 6:24 PM MSTAreal Flood AdvisoryTWCPima2 hr
Aug 2, 6:26 PM MSTAreal Flood AdvisoryTWCCochise, Santa Cruz2 hr
Aug 2, 6:31 PM MSTSpecial Weather StatementTWC59 min
Aug 2, 6:37 PM MSTSevere Thunderstorm WarningTWCPima38 min
Aug 2, 6:55 PM MSTFlash Flood Warning Considerable damage threatTWCPima3 hr
Aug 2, 7:06 PM MSTAreal Flood AdvisoryTWCPinal114 min
Aug 2, 7:06 PM MSTSpecial Weather StatementTWCCochise39 min
Aug 2, 7:15 PM MSTSpecial Weather StatementTWCSanta Cruz45 min
Aug 2, 7:25 PM MSTSpecial Weather StatementTWC50 min
Aug 2, 7:31 PM MSTSevere Thunderstorm WarningTWCPima44 min
Aug 2, 8:13 PM MSTSevere Thunderstorm WarningTWCPima33 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.