Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 42, NWS Phoenix, AZ

August 20, 2012La Paz County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Aug 20, 2012, 2:51 PM MST for La Paz County, Arizona. It was in force for 114 min. 2 reports 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 20, 2012, 2:51 PM MST (21:51 UTC)
Expired
Aug 20, 2012, 4:45 PM MST
In force
114 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Flood severity
None

County La Paz County, AZ

The radar

The Yuma radar (KYUX), 173 km from the middle of the area, began a volume at 21:54 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 20, 4:15 PM MSTFLASH FLOODHarcuvar, AZFLOODING AND FLASH FLOODING IN THE WASHES IN AND AROUND HARCUVAR
Aug 20, 4:15 PM MSTFLASH FLOODSalome, AZFLOODING AND FLASH FLOODING IN WASHES IN AND AROUND SALOME

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

The nearest sounding before it

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 9.9 hours before the alert went out and 156 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, Yuma Intl Airpor, AZ at 12:00Z on 2012-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 606 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, Yuma Intl Airpor, AZ at 12:00Z on 2012-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -44 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
606 J/kg
Mixed-layer CIN
-209 J/kg
Mixed-layer LCL
1836 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-44 m²/s²
0-3 km storm-relative helicity
-13 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.

931 
WGUS55 KPSR 202151
FFWPSR
AZC012-202345-
/O.NEW.KPSR.FF.W.0042.120820T2151Z-120820T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
251 PM MST MON AUG 20 2012

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL LA PAZ COUNTY IN WEST CENTRAL ARIZONA...

* UNTIL 445 PM MST

* AT 240 PM MST...STRONG THUNDERSTORMS WITH VERY HEAVY RAIN WERE 
DEVELOPING NEAR THE TOWNS OF WENDEN...HARCUVAR...THE DESERTS EAST
OF BOUSE AND NORTH OF VICKSBURG JUNCTION.  THE ATMOSPHERE IS 
EXCESSIVELY MOIST TODAY. ANY THUNDERSTORM RAIN WILL LIKELY PRODUCE 
FLOOD OR FLASH FLOODING. HIGHWAYS 60 NEAR WENDEN...HIGHWAY 72 TO 
BOUSE...AND THE ALAMO LAKE HIGHWAY ARE ALL VULNERABLE TO FLOODING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT PEOPLE ALONG THE BANKS OF WASHES AND
CREEKS SHOULD MOVE TO HIGHER GROUND IMMEDIATELY. NORMALLY DRY WASHES
AND STREAMS WILL SUDDENLY HAVE RUNNING WATER AND MAKE UNBRIDGED
CROSSINGS IMPASSABLE. STREETS...UNDERPASSES...AND LOW SPOTS WILL
BECOME INUNDATED MAKING DRIVING HAZARDOUS IN THE WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF NORMALLY
DRY WASHES AND CREEKS...ROADS...AND LOW LYING SPOTS. UNBRIDGED
CROSSINGS WILL BE ESPECIALLY DANGEROUS.

&&

LAT...LON 3392 11403 3411 11358 3372 11338 3363 11375

$$

HV
3 follow-up statements
706 
WGUS75 KPSR 202251
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
351 PM MST MON AUG 20 2012

AZC012-202345-
/O.CON.KPSR.FF.W.0042.000000T0000Z-120820T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LA PAZ AZ-
351 PM MST MON AUG 20 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM MST FOR
CENTRAL LA PAZ COUNTY...

A FLASH FLOOD WARNING CONTINUES LA PAZ COUNTY IN THE VICINITY OF THE 
TOWNS OF WENDEN...SALOME...HARCUVAR...BOUSE...AND VICKSBURG JUNCTION.

AT 347 PM LARGE THUNDERSTORMS WITH HEAVY RAIN CONTINUED TO COVER THE 
AREA. THE ATMOSPHERE IS EXCESSIVELY MOIST TODAY AND CAPABLE OF 
PRODUCING FLOOD OR FLASH FLOOD THUNDERSTORM RAINS.  FLOODING IS 
LIKELY OR IMMINENT. INFORMATION FROM THE AREA HAS BEEN DIFFICULT TO 
GET...SO NO REPORTS OF FLOODING HAVE BEEN RECEIVED YET. 


PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT PEOPLE ALONG THE BANKS OF WASHES AND
CREEKS SHOULD MOVE TO HIGHER GROUND IMMEDIATELY. NORMALLY DRY WASHES
AND STREAMS WILL SUDDENLY HAVE RUNNING WATER AND MAKE UNBRIDGED
CROSSINGS IMPASSABLE. STREETS...UNDERPASSES...AND LOW SPOTS WILL
BECOME INUNDATED MAKING DRIVING HAZARDOUS IN THE WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF NORMALLY
DRY WASHES AND CREEKS...ROADS...AND LOW LYING SPOTS. UNBRIDGED
CROSSINGS WILL BE ESPECIALLY DANGEROUS.

&&

LAT...LON 3392 11403 3411 11358 3372 11338 3363 11375

$$

HV
574 
WGUS75 KPSR 202336
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
436 PM MST MON AUG 20 2012

AZC012-202345-
/O.CON.KPSR.FF.W.0042.000000T0000Z-120820T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LA PAZ AZ-
436 PM MST MON AUG 20 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM MST FOR
CENTRAL LA PAZ COUNTY...

THE FLASH FLOOD WARNING FOR AREAS NEAR THE TOWNS OF WENDEN...
SALOME...HARCUVAR...VICKSBURG JUNCTION...AND BOUSE CONTINUES UNTIL 
445 PM.

THERE WERE REPORTS OF FLASH FLOODING IN THE VICINITY OF SALOME. 
PARKER SHERIFF REPORTED NO LIFE THREATENING EMERGENCIES...HOWEVER 
HIGHWAY CREWS WERE OUT IN FORCE TRYING TO MITIGATE SAFETY ISSUES 
FROM FLOODING.

THE FLASH FLOOD WARNING COVERED A LOT OF AREA INCLUDING REMOTE 
DESERTS...SO ADDITIONAL FLOODING WAS LIKELY IN OTHER WASHES. 
MOTORIST ARE STILL ADVISE TO USE CAUTION WHEN TRAVELING IN LA PAZ 
COUNTY NEAR THUNDERSTORM RAINS. IT MAY STILL TAKE TIME FOR WATER TO 
WORK ITS WAY DOWN FROM THE DESERT MOUNTAINS.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT PEOPLE ALONG THE BANKS OF WASHES AND
CREEKS SHOULD MOVE TO HIGHER GROUND IMMEDIATELY. NORMALLY DRY WASHES
AND STREAMS WILL SUDDENLY HAVE RUNNING WATER AND MAKE UNBRIDGED
CROSSINGS IMPASSABLE. STREETS...UNDERPASSES...AND LOW SPOTS WILL
BECOME INUNDATED MAKING DRIVING HAZARDOUS IN THE WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF NORMALLY
DRY WASHES AND CREEKS...ROADS...AND LOW LYING SPOTS. UNBRIDGED
CROSSINGS WILL BE ESPECIALLY DANGEROUS.

&&

LAT...LON 3392 11403 3411 11358 3372 11338 3363 11375

$$

HV
306 
WGUS75 KPSR 202352
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
452 PM MST MON AUG 20 2012

AZC012-202354-
/O.EXP.KPSR.FF.W.0042.000000T0000Z-120820T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LA PAZ AZ-
452 PM MST MON AUG 20 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 445 PM MST FOR CENTRAL LA
PAZ COUNTY...

THE FLASH FLOOD WARNING ISSUED EARLIER FOR LOCATIONS NEAR THE TOWNS 
OF SALOME...HARCUVAR...WENDEN...BOUSE...AND VICKSBURG JUNCTION WAS 
ALLOWED TO EXPIRE AT 445 PM.

HEAVY THUNDERSTORM RAINS IN THE AREA HAVE ENDED. THERE WERE SEVERAL 
REPORTS OF FLOODING IN AND AROUND THE TOWNS OF SALOME AND HARCUVAR.  
FORTUNATELY THERE WERE NO FLOOD EMERGENCIES...AND COUNTY ROAD CREWS 
ARE OUT IN FORCE TRYING TO MITIGATE ANY FLOOD SAFETY ISSUES.

EXTREMELY HEAVY RAIN FELL MOSTLY IN THE REMOTE DESERTS AND DESERT 
MOUNTAINS NORTH AND SOUTH OF THE TOWN OF SALOME. IT IS LIKELY THAT 
ADDITIONAL FLOODING OCCURRED BUT NOT REPORTED.  IT WILL TAKE SOME 
TIME FOR FLOOD WATERS TO SLOWLY RECEDE IN DESERT WASHES.


LAT...LON 3392 11403 3411 11358 3372 11338 3363 11375

$$

HV

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 5:42 PM MSTAreal Flood AdvisoryPSRGila83 min
Aug 19, 5:55 PM MSTSpecial Weather StatementPSRGila80 min
Aug 19, 6:57 PM MSTSpecial Weather StatementPSR78 min
Aug 19, 7:53 PM MSTSpecial Weather StatementPSRPinal82 min
Aug 19, 7:59 PM MSTSpecial Weather StatementPSRPinal76 min
Aug 20, 2:28 PM MSTAreal Flood AdvisoryPSRLa Paz, Maricopa107 min
Aug 20, 2:32 PM MSTSevere Thunderstorm WarningPSRMaricopa28 min
Aug 20, 4:16 PM MSTSpecial Weather StatementPSRLa Paz59 min
Aug 20, 4:47 PM MSTSpecial Weather StatementPSRMaricopa58 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.