Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 29, NWS Phoenix, AZ

July 31, 2012La Paz County, Yuma County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 31, 2012, 11:37 AM MST for La Paz County, Yuma County, Arizona. It was in force for 113 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: Jul 31, 2012, 11:37 AM MST (18:37 UTC)
Expired: Jul 31, 2012, 1:30 PM MST
In force: 113 min
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Flood severity: None

Counties La Paz County, AZ, Yuma County, AZ

The radar

The Yuma radar (KYUX), 141 km from the middle of the area, began a volume at 18:40 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

Time	Report	Where	Remark
Jul 31, 11:55 AM MST	FLASH FLOOD	Ehrenberg, AZ	LA PAZ SHERIFF REPORTS FLASH FLOOD OVER MOHAVE RD. HIGHWAY HAS BEEN CLOSED
Jul 31, 12:40 PM MST	FLASH FLOOD	12 N Quartzsite, AZ	WASHES RUNNING IN NUMEROUS LOCATIONS CLOSED AZ-95.

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

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 6.6 hours before the alert went out and 229 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 808 J/kg
Mixed-layer CIN: -119 J/kg
Mixed-layer LCL: 1373 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 24 m²/s²
0-3 km storm-relative helicity: 15 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.

201 
WGUS55 KPSR 311837
FFWPSR
AZC012-027-312030-
/O.NEW.KPSR.FF.W.0029.120731T1837Z-120731T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
1137 AM MST TUE JUL 31 2012

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL YUMA COUNTY IN SOUTHWEST ARIZONA...
  WESTERN LA PAZ COUNTY IN WEST CENTRAL ARIZONA...

* UNTIL 130 PM MST/130 PM PDT/

* AT 1127 AM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS
  DETECTED VERY HEAVY RAIN THAT WILL CAUSE FLASH FLOODING. BETWEEN   
  1030 AND 1120 AM...IN EXCESS OF 2 INCHES OF RAIN FELL OVER
  AND NEAR ROUTE 95 ABOUT FROM 5 TO 10 MILES NORTH OF                
  QUARTZSITE...AND OVER AND JUST WEST OF PALM CANYON. SOME STREET
  FLOODING WAS REPORTED IN AND AROUND EHRENBERG...WHERE JUST OVER AN
  INCH OF RAIN FELL.       

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROUTE 95   
  BETWEEN QUARTZSITE AND ROUTE 72...THE PALM CANYON AREA AS WELL
  AS ROUTE 95 NEAR PALM CANYON...AND MOHAVE ROAD FROM EHRENBERG TO
  POSTON.   

THIS WARNING REPLACES THE URBAN AND SMALL STREAM FLOOD ADVISORY      
THAT HAD BEEN POSTED EARLIER THIS MORNING. 

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.

&&

LAT...LON 3421 11405 3318 11398 3341 11463 3342 11464
      3355 11453 3365 11453 3366 11451 3367 11453
      3370 11450 3395 11453 3400 11446 3406 11444

$$

DG

2 follow-up statements

358 
WGUS75 KPSR 311929
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
1229 PM MST TUE JUL 31 2012

AZC012-027-312030-
/O.CON.KPSR.FF.W.0029.000000T0000Z-120731T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LA PAZ AZ-YUMA AZ-
1229 PM MST TUE JUL 31 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 PM MST/130 PM
PDT/ FOR NORTH CENTRAL YUMA AND WESTERN LA PAZ COUNTIES...

AT 1217 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED 
TO DETECT SCATTERED THUNDERSTORMS PRODUCING HEAVY RAIN OVER PORTIONS 
OF THE WARNED AREA. HEAVIEST STORMS WERE NEAR PARKER. 

BETWEEN 1030 AM AND NOON...BETWEEN 2 AND 3 AND ONE HALF INCHES OF 
RAIN FELL OVER AND NEAR ROUTE 95 BETWEEN QUARTZSITE AND ROUTE 
72...AND OVER AND NEAR PALM CANYON. SIGNIFICANT FLASH FLOODING IS A 
NEAR-CERTAINTY IN THOSE AREAS...AND OTHER LOCATIONS IN THE WARNED 
AREA WILL LIKELY EXPERIENCE SOME DEGREE OF FLASH FLOODING.  

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROUTE 95... 
ROUTE 72...PARKER...POSTON...EHRENBERG...AND PALM CANYON.

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.

&&

LAT...LON 3421 11405 3318 11398 3341 11463 3342 11464
      3355 11453 3365 11453 3366 11451 3367 11453
      3370 11450 3395 11453 3400 11446 3406 11444

$$

DG

408 
WGUS75 KPSR 312016
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
116 PM MST TUE JUL 31 2012

AZC012-027-312030-
/O.CON.KPSR.FF.W.0029.000000T0000Z-120731T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LA PAZ AZ-YUMA AZ-
116 PM MST TUE JUL 31 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 PM MST/130 PM
PDT/ FOR NORTH CENTRAL YUMA AND WESTERN LA PAZ COUNTIES...

AT 115 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO 
DETECT SCATTERED SCATTER SHOWERS AND THUNDERSTORMS PRODUCING HEAVY 
RAIN OVER PORTIONS OF THE WARNED AREA.

BETWEEN 11 AM AND 1 PM...BETWEEN 2 AND 3 INCHES OF RAIN HAVE FALLEN 
OVER AND NEAR ROUTE 95 BETWEEN QUARTZSITE AND ROUTE 72...AND OVER 
AND NEAR PALM CANYON. COUNTY EMERGENCY MANAGEMENT OFFICIALS REPORT 
NUMEROUS WASHES FLOODED BETWEEN QUARTZITE AND PARKER. THIS IS A 
SIGNIFICANT FLOOD EVENT...WITH RAINFALL TOTALS APPROACHING OR 
EXCEEDING THE 100 YEAR AVERAGE RECURRENCE INTERVAL EVENT.  

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROUTE 95... 
ROUTE 72...PARKER...POSTON...EHRENBERG...AND PALM CANYON.

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.

&&

LAT...LON 3421 11405 3318 11398 3341 11463 3342 11464
      3355 11453 3365 11453 3366 11451 3367 11453
      3370 11450 3395 11453 3400 11446 3406 11444

$$

MCLANE

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 30, 5:12 PM MST	Areal Flood Advisory	PSR	La Paz	2 hr
Jul 30, 11:26 PM MST	Special Weather Statement	PSR	Gila	79 min
Jul 31, 12:31 AM MST	Special Weather Statement	PSR	Gila	59 min
Jul 31, 1:15 AM MST	Special Weather Statement	PSR		45 min
Jul 31, 3:42 AM MST	Flash Flood Watch	PSR		15 hr
Jul 31, 10:16 AM MST	Flash Flood Warning	PSR	La Paz	3 hr
Jul 31, 10:47 AM MST	Areal Flood Advisory	PSR	La Paz, Yuma	52 min
Jul 31, 11:06 AM MST	Special Weather Statement	PSR	La Paz	39 min
Jul 31, 12:05 PM MST	Special Weather Statement	PSR	La Paz	40 min
Jul 31, 12:12 PM MST	Severe Thunderstorm Warning	PSR	La Paz	49 min
Jul 31, 1:31 PM MST	Flash Flood Warning	PSR	La Paz, Yuma	119 min
Jul 31, 4:10 PM MST	Blowing Dust Advisory	PSR		19 min
Jul 31, 4:29 PM MST	Dust Storm Warning	PSR		82 min
Jul 31, 4:48 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	27 min

Nearby

Flash Flood Warnings in Arizona, 2012 Every 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.