Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 65, NWS Phoenix, AZ

September 4, 2012Imperial County, California

NWS Phoenix, AZ issued this flash flood warning at Sep 4, 2012, 4:09 PM PDT for Imperial County, California. It was in force for 92 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
Sep 4, 2012, 4:09 PM PDT (23:09 UTC)
Expired
Sep 4, 2012, 5:41 PM PDT
In force
92 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Flood severity
None

County Imperial County, CA

The radar

The Yuma radar (KYUX), 69 km from the middle of the area, began a volume at 23:10 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

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 11.2 hours before the alert went out and 59 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 2012-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 907 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 2012-09-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 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
907 J/kg
Mixed-layer CIN
-175 J/kg
Mixed-layer LCL
1469 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
12 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.

849 
WGUS55 KPSR 042309
FFWPSR
CAC025-050115-
/O.NEW.KPSR.FF.W.0065.120904T2309Z-120905T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL IMPERIAL COUNTY IN SOUTHEAST CALIFORNIA...

* UNTIL 615 PM PDT

* AT 405 PM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
  VERY HEAVY RAIN THAT WILL CAUSE FLASH FLOODING.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO GLAMIS 
  AND TRAVELERS ALONG STATE 78.

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 3299 11525 3308 11502 3313 11493 3313 11485
      3298 11486 3298 11493 3294 11525

$$

NOLTE
2 follow-up statements
265 
WGUS75 KPSR 042326
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
426 PM PDT TUE SEP 4 2012

CAC025-050115-
/O.CON.KPSR.FF.W.0065.000000T0000Z-120905T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
IMPERIAL CA-
426 PM PDT TUE SEP 4 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM PDT FOR
CENTRAL IMPERIAL COUNTY...

AT 419 PM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
LARGE AREA OF THUNDERSTORM ACTIVITY PRODUCING VERY HEAVY RAIN 
THAT WILL CAUSE FLASH FLOODING.

RADAR ESTIMATES THAT THREE QUARTERS TO OVER ONE INCH OF RAIN HAS
FALLEN IN THE LAST HALF HOUR RIGHT OVER THE STATE ROUTE 78 
CORRIDOR. 

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 3299 11525 3308 11502 3313 11493 3313 11485
      3298 11486 3298 11493 3294 11525

$$

NOLTE
666 
WGUS75 KPSR 050041
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
541 PM PDT TUE SEP 4 2012

CAC025-050050-
/O.CAN.KPSR.FF.W.0065.000000T0000Z-120905T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
IMPERIAL CA-
541 PM PDT TUE SEP 4 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR CENTRAL IMPERIAL
COUNTY...

STORMS PRODUCING HEAVY RAINFALL HAVE ENDED ALONG THE STATE ROUTE 78
CORRIDOR IN EAST CENTRAL IMPERIAL COUNTY. IMPACTS ARE EXPECTED TO
LINGER AS RUNOFF CONTINUES TO MOVE THROUGH THE AREA FROM EARLIER 
STORMS. NORMALLY DRY WASHES MAY BE RUNNING AND EXPECT PONDING OF 
WATER ON ROAD SURFACES...PARTICULARLY LOW LYING PORTIONS. 

LAT...LON 3299 11525 3308 11502 3313 11493 3313 11485
      3298 11486 3298 11493 3294 11525

$$

NOLTE

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 3, 6:41 PM PDTAreal Flood AdvisoryPSRRiverside3 hr
Sep 4, 1:45 PM PDTSpecial Weather StatementPSRRiverside45 min
Sep 4, 1:55 PM PDTFlash Flood WarningPSRRiverside, San Bernardino95 min
Sep 4, 2:42 PM PDTAreal Flood AdvisoryPSRRiverside94 min
Sep 4, 2:54 PM PDTSpecial Weather StatementPSRRiverside66 min
Sep 4, 3:18 PM PDTAreal Flood AdvisoryPSRRiverside, San Bernardino80 min
Sep 4, 3:33 PM PDTSpecial Weather StatementPSRImperial57 min
Sep 4, 3:56 PM PDTBlowing Dust AdvisoryPSR2 hr
Sep 4, 3:57 PM PDTSpecial Weather StatementPSRRiverside78 min
Sep 4, 4:57 PM PDTSpecial Weather StatementPSRRiverside48 min

Nearby

Flash Flood Warnings in California, 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.