Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 43, NWS Tucson, AZ

August 21, 2012Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 21, 2012, 5:45 PM MST for Pima 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 21, 2012, 5:45 PM MST (00:45 UTC)
Expired
Aug 21, 2012, 7:45 PM MST
In force
2 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Pima County, AZ

The radar

The Phoenix radar (KIWA), 97 km from the middle of the area, began a volume at 00:44 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, 0.8 hours before the alert went out and 120 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.

502 
WGUS55 KTWC 220045
FFWTWC
AZC019-220245-
/O.NEW.KTWC.FF.W.0043.120822T0045Z-120822T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

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

* UNTIL 745 PM MST

* AT 540 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM NEAR AND EAST OF SILVER BELL...
  INCLUDING SILVER BELL ROAD...OR 15 MILES WEST OF MARANA...MOVING
  NORTHWEST AT 5 MPH.

* THE STORM PRODUCING FLASH FLOODING WILL OTHERWISE REMAIN OVER
  MAINLY RURAL AREAS OF THE INDICATED COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3249 11168 3249 11136 3234 11131 3231 11149

$$

MEYER
2 follow-up statements
292 
WGUS75 KTWC 220127
FFSTWC

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

AZC019-220245-
/O.CON.KTWC.FF.W.0043.000000T0000Z-120822T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
627 PM MST TUE AUG 21 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM MST FOR NORTH
CENTRAL PIMA COUNTY...

AT 620 PM MST...SHOWERS AND THUNDERSTORMS WERE STARTING TO WEAKEN 
NEAR SILVER BELL WEST OF MARANA. RAINFALL AMOUNTS IN EXCESS OF 2 
INCHES IN THE AREA WAS CAUSING FLASH FLOODING...INCLUDING SILVER 
BELL ROAD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS INCLUDES THE FOLLOWING STREAMS AND DRAINAGES...LOS ROBLES 
WASH...BLANCO WASH...COCIO WASH...HOUSE WASH...EL TIRO WASH AND 
MAMMOTH WASH.

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

&&

LAT...LON 3249 11168 3249 11136 3234 11131 3231 11149

$$

MEYER
244 
WGUS75 KTWC 220244
FFSTWC

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

AZC019-220253-
/O.EXP.KTWC.FF.W.0043.000000T0000Z-120822T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
744 PM MST TUE AUG 21 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 745 PM MST FOR NORTH
CENTRAL PIMA COUNTY...

AT 743 PM MST SHOWERS AND THUNDERSTORMS HAD GENERALLY ENDED AROUND 
THE SILVER BELL AND SILVER BELL ROAD AREA WEST OF MARANA. EXPECT 
HEAVY FLOW IN NORMALLY DRY STREAMBEDS AND WASHES...AS WELL AS SOME 
ROAD FLOODING...TO CONTINUE INTO THE EARLY MORNING HOURS. A FLASH 
FLOOD WARNING REMAINS IN EFFECT JUST WEST OF THIS AREA. AN URBAN AND 
SMALL STREAM FLOOD ADVISORY REMAINS IN EFFECT UNTIL AFTER MIDNIGHT. 

LAT...LON 3249 11168 3249 11136 3234 11131 3231 11149

$$

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, 5:48 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, 7:51 PM MSTFlash Flood WarningTWCPima114 min
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.