Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 45, NWS Tucson, AZ

August 21, 2012Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 21, 2012, 7:51 PM MST for Pima County, Arizona. It was in force for 114 min. 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 21, 2012, 7:51 PM MST (02:51 UTC)
Expired
Aug 21, 2012, 9:45 PM MST
In force
114 min
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Pima County, AZ

The radar

The Phoenix radar (KIWA), 114 km from the middle of the area, began a volume at 02:52 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

Phoenix, AZ (KPSR), launched 00:00Z, 2.9 hours before the alert went out and 126 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, Phoenix, AZ at 00:00Z on 2012-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 565 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, Phoenix, AZ at 00:00Z on 2012-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 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
565 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
2143 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

810 
WGUS55 KTWC 220251
FFWTWC
AZC019-220445-
/O.NEW.KTWC.FF.W.0045.120822T0251Z-120822T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
751 PM MST TUE AUG 21 2012

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL PIMA COUNTY IN SOUTH CENTRAL ARIZONA...

* UNTIL 945 PM MST

* AT 742 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED
  TO SHOW A LARGE AREA OF STRONG THUNDERSTORMS GENERATING WIDESPREAD
  RAINFALL IN EXCESS OF OF 2 INCHES WITH SOME LOCATIONS OVER 3 INCHES
  ACROSS MAINLY CENTRAL AND NORTHERN PORTIONS OF THE TOHONO O'ODHAM
  NATION.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SANTA
  ROSA...SIL NAGGIA...QUEENS WELL...AK CHIN...COVERED WELLS...AND
  PISINIMO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF WASHES
AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND OTHER DRAINAGE
AREAS AND LOW LYING SPOTS.

&&

LAT...LON 3249 11169 3229 11147 3195 11216 3204 11239
      3250 11234

$$

MEYER
2 follow-up statements
572 
WGUS75 KTWC 220344
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
844 PM MST TUE AUG 21 2012

AZC019-220445-
/O.CON.KTWC.FF.W.0045.000000T0000Z-120822T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
844 PM MST TUE AUG 21 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 PM MST FOR
CENTRAL PIMA COUNTY...

AT 836 PM MST...SHOWERS AND THUNDERSTORMS WERE FINALLY WEAKENING 
ACROSS MOST OF CENTRAL AND NORTHERN PORTIONS OF THE TOHONO O'ODHAM 
NATION. HEAVY RUNOFF FROM EXTREMELY HEAVY RAINFALL AMOUNTS OVER THE 
PAST FEW HOURS...WITH SOME LOCATIONS IN EXCESS OF 3 TO 4 
INCHES...WILL CONTINUE TO GENERATE FLOODING CONDITIONS OVERNIGHT.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SANTA 
ROSA...SIL NAGGIA...QUEENS WELL...AK CHIN...COVERED WELLS...AND   
PISINIMO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF WASHES 
AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND OTHER DRAINAGE 
AREAS AND LOW LYING SPOTS.

&&

LAT...LON 3249 11169 3229 11147 3195 11216 3204 11239
      3250 11234

$$

MEYER
470 
WGUS75 KTWC 220449
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
949 PM MST TUE AUG 21 2012

AZC019-220458-
/O.EXP.KTWC.FF.W.0045.000000T0000Z-120822T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
949 PM MST TUE AUG 21 2012

...THE FLASH FLOOD WARNING HAS EXPIRED FOR CENTRAL PIMA COUNTY...

AT 945 PM MST ONLY LIGHT SHOWERS REMAINED ACROSS PIMA COUNTY AND THE 
TOHONO O'ODHAM NATION. EXTREMELY HEAVY RAINFALL EARLIER IN THE 
EVENING WILL CAUSE HEAVY RUNOFF TO CONTINUE INTO THE EARLY MORNING 
HOURS. AN URBAN AND SMALL STREAM FLOOD ADVISORY REMAINS IN EFFECT 
UNTIL 115 AM MST.

LAT...LON 3249 11169 3229 11147 3195 11216 3204 11239
      3250 11234

$$

MEYER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 5:03 PM MSTSpecial Weather StatementTWCPinal57 min
Aug 21, 5:21 PM MSTSpecial Weather StatementTWCPinal39 min
Aug 21, 5:37 PM MSTFlash Flood WarningTWCPinal83 min
Aug 21, 5:39 PM MSTFlash Flood WarningTWCPima85 min
Aug 21, 5:45 PM MSTFlash Flood WarningTWCPima2 hr
Aug 21, 5:48 PM MSTSevere Thunderstorm WarningTWCPima42 min
Aug 21, 5:53 PM MSTSpecial Weather StatementTWCPinal52 min
Aug 21, 6:38 PM MSTFlash Flood WarningTWCPima112 min
Aug 21, 6:47 PM MSTSevere Thunderstorm WarningTWCPima43 min
Aug 21, 6:55 PM MSTSevere Thunderstorm WarningTWCPima50 min
Aug 21, 7:13 PM MSTAreal Flood AdvisoryTWCPima6 hr
Aug 21, 8:31 PM MSTSpecial Weather StatementTWC44 min
Aug 21, 10:29 PM MSTAreal Flood WarningTWCPima3 hr
Aug 22, 2:12 AM MSTAreal Flood WarningTWCPima12 hr
Aug 22, 3:08 AM MSTFlash Flood WatchTWCCochise, Pima, Pinal, Santa Cruz17 hr
Aug 22, 9:35 AM MSTAreal Flood AdvisoryTWCCochise, Graham, Pima, Pinal, Santa Cruz3 hr
Aug 22, 2:28 PM MSTAreal Flood WarningTWCPima, Pinal7 hr

Nearby

Flash Flood Warnings in Arizona, 2012Every flash flood warning in 2012

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.