Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 67, NWS Phoenix, AZ

September 4, 2012Maricopa County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Sep 4, 2012, 9:09 PM MST for Maricopa 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: Sep 4, 2012, 9:09 PM MST (04:09 UTC)
Expired: Sep 4, 2012, 11:26 PM MST
In force: 2 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Flood severity: None

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 132 km from the middle of the area, began a volume at 04:13 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, 4.2 hours before the alert went out and 112 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: 386 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 2024 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: -20 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.

793 
WGUS55 KPSR 050409
FFWPSR
AZC013-050715-
/O.NEW.KPSR.FF.W.0067.120905T0409Z-120905T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
909 PM MST TUE SEP 4 2012

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHWESTERN MARICOPA COUNTY IN SOUTH CENTRAL ARIZONA...
  THIS INCLUDES GILA BEND...

* UNTIL 1215 AM MST

* AT 903 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
  VERY HEAVY RAIN THAT WILL CAUSE FLASH FLOODING. UP TO 2 INCHES 
  OF RAIN HAS FALLEN NORTH AND WEST OF GILA BEND...AND AN ADDITIONAL
  1 INCH IS EXPECTED. THIS WILL COMBINE WITH RUNOFF FROM EARLIER
  STORMS TO THE NORTH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO COTTON
  CENTER...SENTINEL...HIGHWAY 85 NORTH OF GILA BEND...AND THE
  INTERSTATE 8 CORRIDOR WEST OF GILA BEND.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING
FLOODED ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3271 11330 3308 11332 3320 11262 3286 11250

$$

WOODALL

3 follow-up statements

788 
WGUS75 KPSR 050447
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
947 PM MST TUE SEP 4 2012

AZC013-050715-
/O.CON.KPSR.FF.W.0067.000000T0000Z-120905T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARICOPA AZ-
947 PM MST TUE SEP 4 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1215 AM MST FOR
SOUTHWESTERN MARICOPA COUNTY...

AT 941 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED 
THUNDERSTORMS PRODUCING VERY HEAVY RAIN TO THE SOUTHWEST OF GILA 
BEND.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO GILA BEND 
AUXILIARY FIELD...COTTON CENTER...BOSQUE...SENTINEL AND GILA BEND.

UP TO 1.75 INCHES OF RAIN HAS FALLEN IN THE WARNING AREA SINCE 
845 PM...WITH AN ADDITIONAL 1 INCH EXPECTED. THE HEAVY RAIN WILL 
COMBINE WITH RUNOFF FROM AREAS NORTH OF THE INTERSTATE 8 CORRIDOR TO 
CONTINUE THE THREAT OF 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.

MOST FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING
FLOODED ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3271 11330 3308 11332 3320 11262 3286 11250

$$

WOODALL

973 
WGUS75 KPSR 050535
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
1035 PM MST TUE SEP 4 2012

AZC013-050715-
/O.CON.KPSR.FF.W.0067.000000T0000Z-120905T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARICOPA AZ-
1035 PM MST TUE SEP 4 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1215 AM MST FOR
SOUTHWESTERN MARICOPA COUNTY...

AT 1032 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED 
MODERATE RAIN BETWEEN GILA BEND AND SENTINEL. MOVEMENT WAS SOUTH AT 
15 MPH.

ALTHOUGH THE HEAVY RAIN HAS MOVED SOUTH OF THE WARNING AREA...RUNOFF 
FROM THE EARLIER RAIN WILL CONTINUE TO POSE A THREAT FOR FLOODING.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO COTTON 
CENTER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE EXTRA CAUTIOUS AT NIGHT WHEN FLOODING IS HARDER TO SEE. MOST 
FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING FLOODED 
ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

TO REPORT FLOODING...PLEASE RELAY YOUR REPORT TO LOCAL LAW
ENFORCEMENT WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 3305 11330 3317 11268 3285 11259 3281 11277
      3272 11326

$$

WOODALL

888 
WGUS75 KPSR 050626 RRA
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
1126 PM MST TUE SEP 4 2012

AZC013-050636-
/O.CAN.KPSR.FF.W.0067.000000T0000Z-120905T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARICOPA AZ-
1126 PM MST TUE SEP 4 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHWESTERN
MARICOPA COUNTY...

HEAVY RAIN HAS ENDED ACROSS SOUTHWEST MARICOPA COUNTY. RUNOFF FROM 
PREVIOUS STORMS WILL CONTINUE INTO THE EARLY MORNING HOURS HOWEVER 
FLASH FLOODING IS NO LONGER ANTICIPATED. CONTINUE TO USE CAUTION IF 
TRAVELING OVERNIGHT AND DO NOT ENTER ANY AREAS WHERE WATER IS 
FLOWING OVER THE ROADWAY.

LAT...LON 3305 11330 3317 11268 3285 11259 3281 11277
      3272 11326

$$

LEINS

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 4, 5:25 PM MST	Special Weather Statement	PSR	Maricopa	50 min
Sep 4, 6:01 PM MST	Areal Flood Advisory	PSR	Gila	119 min
Sep 4, 6:42 PM MST	Special Weather Statement	PSR	Maricopa	33 min
Sep 4, 7:06 PM MST	Areal Flood Advisory	PSR	Maricopa	114 min
Sep 4, 7:06 PM MST	Areal Flood Advisory	PSR	La Paz, Maricopa	114 min
Sep 4, 8:30 PM MST	Blowing Dust Advisory	PSR		90 min
Sep 4, 8:35 PM MST	Areal Flood Advisory	PSR	Maricopa, Yuma	115 min
Sep 4, 8:45 PM MST	Areal Flood Advisory	PSR	Pinal	2 hr
Sep 4, 9:42 PM MST	Areal Flood Advisory	PSR	Maricopa	2 hr
Sep 4, 10:14 PM MST	Flash Flood Warning	PSR	Maricopa	72 min
Sep 5, 3:27 PM MST	Special Weather Statement	PSR		33 min
Sep 5, 4:23 PM MST	Special Weather Statement	PSR		22 min
Sep 5, 4:53 PM MST	Special Weather Statement	PSR		37 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.